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	<id>http://www.decodingthedisciplines.de/w/index.php?action=history&amp;feed=atom&amp;title=Function</id>
	<title>Function - Revision history</title>
	<link rel="self" type="application/atom+xml" href="http://www.decodingthedisciplines.de/w/index.php?action=history&amp;feed=atom&amp;title=Function"/>
	<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;action=history"/>
	<updated>2026-05-06T12:27:21Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
	<generator>MediaWiki 1.39.7</generator>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3110&amp;oldid=prev</id>
		<title>Riegler: Changed categories.</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3110&amp;oldid=prev"/>
		<updated>2025-04-22T16:36:00Z</updated>

		<summary type="html">&lt;p&gt;Changed categories.&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 18:36, 22 April 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l32&quot;&gt;Line 32:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 32:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Bottleneck]]&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Bottleneck]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Mathematics]]&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:Mathematics]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:Decoding Interview]]&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;

&lt;!-- diff cache key bluespice:diff::1.12:old-3103:rev-3110 --&gt;
&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3103&amp;oldid=prev</id>
		<title>Riegler at 16:30, 22 April 2025</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3103&amp;oldid=prev"/>
		<updated>2025-04-22T16:30:50Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 18:30, 22 April 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l13&quot;&gt;Line 13:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 13:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from the action to the process stage.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from the action to the process stage.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Step 1: &lt;/ins&gt;Description of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students don&amp;#039;t grasp the concept of functions in a calculus class.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students don&amp;#039;t grasp the concept of functions in a calculus class.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of mental moves needed to overcome the bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Step 2: &lt;/ins&gt;Description of mental moves needed to overcome the bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;

&lt;!-- diff cache key bluespice:diff::1.12:old-3092:rev-3103 --&gt;
&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3092&amp;oldid=prev</id>
		<title>Riegler: -typos</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3092&amp;oldid=prev"/>
		<updated>2025-04-22T13:27:18Z</updated>

		<summary type="html">&lt;p&gt;-typos&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 15:27, 22 April 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Core findings from mathematics education research==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Core findings from mathematics education research==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students conceptual difficulties with respect to functions have been investigated at least since the 1980s. These findings have led to the development of APOS Theory&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; which is a general constructivist theory explaining how mathematical understanding works and develops. It models what might happen in a person&amp;#039;s mind when one tries to learn a mathematical concept. It postulates that a person&amp;#039;s understanding of a mathematical topic develops as &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;one &lt;/del&gt;constructs or reconstructs certain mental structures and organizes them into schemas. The mental structures proposed by APOS theory are actions, processes, objects and schemata; hence the acronym APOS.   &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students conceptual difficulties with respect to functions have been investigated at least since the 1980s. These findings have led to the development of APOS Theory&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; which is a general constructivist theory explaining how mathematical understanding works and develops. It models what might happen in a person&amp;#039;s mind when one tries to learn a mathematical concept. It postulates that a person&amp;#039;s understanding of a mathematical topic develops as &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;the person &lt;/ins&gt;constructs or reconstructs certain mental structures and organizes them into schemas. The mental structures proposed by APOS theory are actions, processes, objects and schemata; hence the acronym APOS.   &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;mathemtics&lt;/del&gt;, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;mathematics&lt;/ins&gt;, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are two core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[Treshold concept|treshold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are two core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[Treshold concept|treshold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3067&amp;oldid=prev</id>
		<title>Riegler: typo</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3067&amp;oldid=prev"/>
		<updated>2025-03-28T08:20:45Z</updated>

		<summary type="html">&lt;p&gt;typo&lt;/p&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 10:20, 28 March 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l6&quot;&gt;Line 6:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 6:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are two core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Treshhold &lt;/del&gt;concept|&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;treshhold &lt;/del&gt;concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are two core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Treshold &lt;/ins&gt;concept|&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;treshold &lt;/ins&gt;concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;

&lt;!-- diff cache key bluespice:diff::1.12:old-3056:rev-3067 --&gt;
&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3056&amp;oldid=prev</id>
		<title>Riegler: -typos</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3056&amp;oldid=prev"/>
		<updated>2025-03-27T17:52:08Z</updated>

		<summary type="html">&lt;p&gt;-typos&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 19:52, 27 March 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l6&quot;&gt;Line 6:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 6:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;twoe &lt;/del&gt;core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[Treshhold concept|treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;two &lt;/ins&gt;core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[Treshhold concept|treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In their book [[Overcoming Student Learning Bottlenecks]] [[:Category:Middendorf, J|Joan Middendorf]] and [[:Category:Shopkow, L|Leah Shopkow]] give excerpts of two [[Step 2 - Decoding Interview|Decoding Interviews]] dealing with the concept of function.&amp;lt;ref&amp;gt;Middendorf, J., &amp;amp; Shopkow, L. (2017). [[Overcoming Student Learning Bottlenecks|&amp;#039;&amp;#039;Overcoming student learning bottlenecks: Decode the critical thinking of your discipline&amp;#039;&amp;#039;.]] Stylus Publishing, LLC, pp. 55-57.&amp;lt;/ref&amp;gt; There, however, the focus is on posing suitable [[interview questions]].&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In their book [[Overcoming Student Learning Bottlenecks]] [[:Category:Middendorf, J|Joan Middendorf]] and [[:Category:Shopkow, L|Leah Shopkow]] give excerpts of two [[Step 2 - Decoding Interview|Decoding Interviews]] dealing with the concept of function.&amp;lt;ref&amp;gt;Middendorf, J., &amp;amp; Shopkow, L. (2017). [[Overcoming Student Learning Bottlenecks|&amp;#039;&amp;#039;Overcoming student learning bottlenecks: Decode the critical thinking of your discipline&amp;#039;&amp;#039;.]] Stylus Publishing, LLC, pp. 55-57.&amp;lt;/ref&amp;gt; There, however, the focus is on posing suitable [[interview questions]].&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from action to process stage.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;the &lt;/ins&gt;action to &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;the &lt;/ins&gt;process stage.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l19&quot;&gt;Line 19:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 19:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Trying not to think of a function in terms of an algorithmic relationship between input and output, for instance via visualing functions as graphs&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Trying not to think of a function in terms of an algorithmic relationship between input and output&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;. This can be achieved&lt;/ins&gt;, for instance&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;, &lt;/ins&gt;via visualing functions as graphs&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Having available examples of input-output relationsships which can be described as functions but not algorithmically (e.g. random processes in the stock market)&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Having available &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;for oneself &lt;/ins&gt;examples of input-output relationsships which can be described as functions but not algorithmically (e.g. random processes in the stock market)&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Available resources==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Available resources==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;

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&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3051&amp;oldid=prev</id>
		<title>Riegler: +typo</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3051&amp;oldid=prev"/>
		<updated>2025-03-26T14:57:32Z</updated>

		<summary type="html">&lt;p&gt;+typo&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
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				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 16:57, 26 March 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l6&quot;&gt;Line 6:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 6:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics, different mental structures are required depending on the developmental stage of understanding. At the action stage, a function is seen merely as an instruction that specifies how the function value (output) is to be calculated. In the process stage, a function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule/algorithm. At the object stage, the function becomes an object, which in turn can itself be affected or manipulated by processes (e.g. differentiation). Going even further, functions can be organized as objects with other mathematical processes or objects to form larger schematas (e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are twoe core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Note that there are twoe core transitions in a person&amp;#039;s conceptualization of function: from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Treshhold concept|&lt;/ins&gt;treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;

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&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3050&amp;oldid=prev</id>
		<title>Riegler: proof reading</title>
		<link rel="alternate" type="text/html" href="http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3050&amp;oldid=prev"/>
		<updated>2025-03-26T14:51:18Z</updated>

		<summary type="html">&lt;p&gt;proof reading&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 16:51, 26 March 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Functions&amp;#039;&amp;#039;&amp;#039; are a core concept of mathematics &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;and &lt;/del&gt;disciplines using mathematics. Difficulties related to the concept of function are well documented and analyzed in mathematics education research&amp;lt;ref&amp;gt;Sfard, A. (1991). On the dual nature of mathematical conceptions: Reflections on processes and objects as different sides of the same coin. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;22&amp;#039;&amp;#039;(1), 1-36.&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;Breidenbach, D., Dubinsky, E., Hawks, J., &amp;amp; Nichols, D. (1992). Development of the process conception of function. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;23&amp;#039;&amp;#039;(3), 247-285.&amp;lt;/ref&amp;gt; &amp;lt;ref name=&amp;quot;:0&amp;quot;&amp;gt;lana Arnon, Jim Cottrill, Ed Dubinsky, Asuman Oktaç, Solange Roa Fuentes, Maria Trigueros, Kirk Weller: APOS theory: a framework for research and curriculum development in mathematics education. Springer, New York Heidelberg 2014, [https://de.wikipedia.org/wiki/Spezial:ISBN-Suche/9781461479659 ISBN 978-1-4614-7965-9].&amp;lt;/ref&amp;gt; and other disciplines (e.g. computer science&amp;lt;ref&amp;gt;Philipp Marwan, Peter Riegler (2011): Entwicklung des Funktionenkonzepts bei Studierenden der Informatik, Wismarer Frege–Reihe, vol. 02/2011.&amp;lt;/ref&amp;gt;, physics&amp;lt;ref&amp;gt;Combining mathematics and physics beyond the introductory level: the case of partial differential equations, https://research.kuleuven.be/portal/en/project/3E211102&amp;lt;/ref&amp;gt;).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Functions&amp;#039;&amp;#039;&amp;#039; are a core concept of mathematics &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;as well as of &lt;/ins&gt;disciplines using mathematics. Difficulties related to the concept of function are well documented and analyzed in mathematics education research&amp;lt;ref&amp;gt;Sfard, A. (1991). On the dual nature of mathematical conceptions: Reflections on processes and objects as different sides of the same coin. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;22&amp;#039;&amp;#039;(1), 1-36.&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;Breidenbach, D., Dubinsky, E., Hawks, J., &amp;amp; Nichols, D. (1992). Development of the process conception of function. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;23&amp;#039;&amp;#039;(3), 247-285.&amp;lt;/ref&amp;gt; &amp;lt;ref name=&amp;quot;:0&amp;quot;&amp;gt;lana Arnon, Jim Cottrill, Ed Dubinsky, Asuman Oktaç, Solange Roa Fuentes, Maria Trigueros, Kirk Weller: APOS theory: a framework for research and curriculum development in mathematics education. Springer, New York Heidelberg 2014, [https://de.wikipedia.org/wiki/Spezial:ISBN-Suche/9781461479659 ISBN 978-1-4614-7965-9].&amp;lt;/ref&amp;gt; and other disciplines (e.g. computer science&amp;lt;ref&amp;gt;Philipp Marwan, Peter Riegler (2011): Entwicklung des Funktionenkonzepts bei Studierenden der Informatik, Wismarer Frege–Reihe, vol. 02/2011.&amp;lt;/ref&amp;gt;, physics&amp;lt;ref&amp;gt;Combining mathematics and physics beyond the introductory level: the case of partial differential equations, https://research.kuleuven.be/portal/en/project/3E211102&amp;lt;/ref&amp;gt;).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Core findings from mathematics education research==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Core findings from mathematics education research==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students conceptual difficulties with respect to functions have been investigated at least since the 1980s. These findings have led to the development of APOS Theory&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; which is a general constructivist theory explaining how mathematical understanding works and develops. It models what might happen in a person&amp;#039;s mind when &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;they try &lt;/del&gt;to learn a mathematical concept. It postulates that a person&amp;#039;s understanding of a mathematical topic develops as &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;they construct &lt;/del&gt;or &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;reconstruct &lt;/del&gt;certain mental structures and &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;organize &lt;/del&gt;them into schemas. The mental structures proposed by APOS theory are actions, processes, objects and schemata; hence the acronym APOS.   &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students conceptual difficulties with respect to functions have been investigated at least since the 1980s. These findings have led to the development of APOS Theory&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; which is a general constructivist theory explaining how mathematical understanding works and develops. It models what might happen in a person&amp;#039;s mind when &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;one tries &lt;/ins&gt;to learn a mathematical concept. It postulates that a person&amp;#039;s understanding of a mathematical topic develops as &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;one constructs &lt;/ins&gt;or &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;reconstructs &lt;/ins&gt;certain mental structures and &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;organizes &lt;/ins&gt;them into schemas. The mental structures proposed by APOS theory are actions, processes, objects and schemata; hence the acronym APOS.   &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;a &lt;/del&gt;different mental &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;structure is in the foreground &lt;/del&gt;depending on the developmental stage of understanding. At the action stage, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;the &lt;/del&gt;function is seen merely as an instruction that specifies how the function value is to be calculated. In the process stage, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;the &lt;/del&gt;function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule. At the object stage, the function becomes an object, which in turn can itself be affected by processes (e.g. differentiation). Going even further, functions can be &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;organised &lt;/del&gt;as objects with other mathematical processes or objects to form &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;schemes &lt;/del&gt;(e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In case of functions in mathemtics&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;, &lt;/ins&gt;different mental &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;structures are required &lt;/ins&gt;depending on the developmental stage of understanding. At the action stage, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;a &lt;/ins&gt;function is seen merely as an instruction that specifies how the function value &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;(output) &lt;/ins&gt;is to be calculated. In the process stage, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;a &lt;/ins&gt;function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;/algorithm&lt;/ins&gt;. At the object stage, the function becomes an object, which in turn can itself be affected &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;or manipulated &lt;/ins&gt;by processes (e.g. differentiation). Going even further, functions can be &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;organized &lt;/ins&gt;as objects with other mathematical processes or objects to form &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;larger schematas &lt;/ins&gt;(e.g. function spaces).  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Core &lt;/del&gt;transitions in a person&amp;#039;s conceptualization of function &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;are &lt;/del&gt;from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Note that there are twoe core &lt;/ins&gt;transitions in a person&amp;#039;s conceptualization of function&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;: &lt;/ins&gt;from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Decoding work done==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In their book [[Overcoming Student Learning Bottlenecks]] [[:Category:&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Shopkow&lt;/del&gt;, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;L&lt;/del&gt;|&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Leah Shopkow&lt;/del&gt;]] and [[:Category:&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Middendorf&lt;/del&gt;, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;J&lt;/del&gt;|&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Joan Middendorf&lt;/del&gt;]] give excerpts of two [[Step 2 - Decoding Interview|Decoding Interviews]] dealing with the concept of function.&amp;lt;ref&amp;gt;Middendorf, J., &amp;amp; Shopkow, L. (2017). [[Overcoming Student Learning Bottlenecks|&amp;#039;&amp;#039;Overcoming student learning bottlenecks: Decode the critical thinking of your discipline&amp;#039;&amp;#039;.]] Stylus Publishing, LLC, pp. 55-57.&amp;lt;/ref&amp;gt; There, however, the focus is on posing suitable [[interview questions]].&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In their book [[Overcoming Student Learning Bottlenecks]] [[:Category:&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Middendorf&lt;/ins&gt;, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;J&lt;/ins&gt;|&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Joan Middendorf&lt;/ins&gt;]] and [[:Category:&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Shopkow&lt;/ins&gt;, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;L&lt;/ins&gt;|&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Leah Shopkow&lt;/ins&gt;]] give excerpts of two [[Step 2 - Decoding Interview|Decoding Interviews]] dealing with the concept of function.&amp;lt;ref&amp;gt;Middendorf, J., &amp;amp; Shopkow, L. (2017). [[Overcoming Student Learning Bottlenecks|&amp;#039;&amp;#039;Overcoming student learning bottlenecks: Decode the critical thinking of your discipline&amp;#039;&amp;#039;.]] Stylus Publishing, LLC, pp. 55-57.&amp;lt;/ref&amp;gt; There, however, the focus is on posing suitable [[interview questions]].&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from action to process stage.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;In terms of APOS-theory the identified bottleneck is related to the conceptual transition from action to process stage.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Identification &lt;/del&gt;of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Description &lt;/ins&gt;of bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students don&amp;#039;t grasp the concept of functions in a calculus class.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Students don&amp;#039;t grasp the concept of functions in a calculus class.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of mental &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;tasks &lt;/del&gt;needed to overcome the bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;===Description of mental &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;moves &lt;/ins&gt;needed to overcome the bottleneck===&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The two interview excerpts revealed the  following mental moves:&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Trying not to think of a function in terms of an algorithmic relationship between input and output, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;e.g. by &lt;/del&gt;visualing functions as graphs&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Trying not to think of a function in terms of an algorithmic relationship between input and output, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;for instance via &lt;/ins&gt;visualing functions as graphs&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Having available examples of input-output relationsships which can be described as functions but not algorithmically (e.g. random processes in the stock market)&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;*Having available examples of input-output relationsships which can be described as functions but not algorithmically (e.g. random processes in the stock market)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br/&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Riegler</name></author>
	</entry>
	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3049&amp;oldid=prev</id>
		<title>Riegler: Changed categories.</title>
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		<updated>2025-03-26T14:09:23Z</updated>

		<summary type="html">&lt;p&gt;Changed categories.&lt;/p&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 16:09, 26 March 2025&lt;/td&gt;
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		<author><name>Riegler</name></author>
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	<entry>
		<id>http://www.decodingthedisciplines.de/w/index.php?title=Function&amp;diff=3048&amp;oldid=prev</id>
		<title>Riegler: init</title>
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		<updated>2025-03-26T14:09:05Z</updated>

		<summary type="html">&lt;p&gt;init&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Functions&amp;#039;&amp;#039;&amp;#039; are a core concept of mathematics and disciplines using mathematics. Difficulties related to the concept of function are well documented and analyzed in mathematics education research&amp;lt;ref&amp;gt;Sfard, A. (1991). On the dual nature of mathematical conceptions: Reflections on processes and objects as different sides of the same coin. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;22&amp;#039;&amp;#039;(1), 1-36.&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;Breidenbach, D., Dubinsky, E., Hawks, J., &amp;amp; Nichols, D. (1992). Development of the process conception of function. &amp;#039;&amp;#039;Educational studies in mathematics&amp;#039;&amp;#039;, &amp;#039;&amp;#039;23&amp;#039;&amp;#039;(3), 247-285.&amp;lt;/ref&amp;gt; &amp;lt;ref name=&amp;quot;:0&amp;quot;&amp;gt;lana Arnon, Jim Cottrill, Ed Dubinsky, Asuman Oktaç, Solange Roa Fuentes, Maria Trigueros, Kirk Weller: APOS theory: a framework for research and curriculum development in mathematics education. Springer, New York Heidelberg 2014, [https://de.wikipedia.org/wiki/Spezial:ISBN-Suche/9781461479659 ISBN 978-1-4614-7965-9].&amp;lt;/ref&amp;gt; and other disciplines (e.g. computer science&amp;lt;ref&amp;gt;Philipp Marwan, Peter Riegler (2011): Entwicklung des Funktionenkonzepts bei Studierenden der Informatik, Wismarer Frege–Reihe, vol. 02/2011.&amp;lt;/ref&amp;gt;, physics&amp;lt;ref&amp;gt;Combining mathematics and physics beyond the introductory level: the case of partial differential equations, https://research.kuleuven.be/portal/en/project/3E211102&amp;lt;/ref&amp;gt;). &lt;br /&gt;
&lt;br /&gt;
==Core findings from mathematics education research==&lt;br /&gt;
Students conceptual difficulties with respect to functions have been investigated at least since the 1980s. These findings have led to the development of APOS Theory&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; which is a general constructivist theory explaining how mathematical understanding works and develops. It models what might happen in a person&amp;#039;s mind when they try to learn a mathematical concept. It postulates that a person&amp;#039;s understanding of a mathematical topic develops as they construct or reconstruct certain mental structures and organize them into schemas. The mental structures proposed by APOS theory are actions, processes, objects and schemata; hence the acronym APOS.  &lt;br /&gt;
&lt;br /&gt;
In case of functions in mathemtics a different mental structure is in the foreground depending on the developmental stage of understanding. At the action stage, the function is seen merely as an instruction that specifies how the function value is to be calculated. In the process stage, the function is seen as a process that assigns an output to every possible input. This process can be thought of without the need to execute or know the instructions specified in the function&amp;#039;s calculation rule. At the object stage, the function becomes an object, which in turn can itself be affected by processes (e.g. differentiation). Going even further, functions can be organised as objects with other mathematical processes or objects to form schemes (e.g. function spaces). &lt;br /&gt;
&lt;br /&gt;
Core transitions in a person&amp;#039;s conceptualization of function are from action to process stage (referred to as interiorization in APOS) and from process to object stage (referred to as encapsulation). In terms of [[treshhold concepts]] both transitions can be considered as thresholds. This indicates the cognitive complexity of the function concept since acquiring it requires multiple (re-)conceptualizations.&lt;br /&gt;
&lt;br /&gt;
==Decoding work done==&lt;br /&gt;
In their book [[Overcoming Student Learning Bottlenecks]] [[:Category:Shopkow, L|Leah Shopkow]] and [[:Category:Middendorf, J|Joan Middendorf]] give excerpts of two [[Step 2 - Decoding Interview|Decoding Interviews]] dealing with the concept of function.&amp;lt;ref&amp;gt;Middendorf, J., &amp;amp; Shopkow, L. (2017). [[Overcoming Student Learning Bottlenecks|&amp;#039;&amp;#039;Overcoming student learning bottlenecks: Decode the critical thinking of your discipline&amp;#039;&amp;#039;.]] Stylus Publishing, LLC, pp. 55-57.&amp;lt;/ref&amp;gt; There, however, the focus is on posing suitable [[interview questions]].&lt;br /&gt;
&lt;br /&gt;
In terms of APOS-theory the identified bottleneck is related to the conceptual transition from action to process stage.&lt;br /&gt;
&lt;br /&gt;
===Identification of bottleneck===&lt;br /&gt;
Students don&amp;#039;t grasp the concept of functions in a calculus class.&lt;br /&gt;
&lt;br /&gt;
===Description of mental tasks needed to overcome the bottleneck===&lt;br /&gt;
The two interview excerpts revealed the  following mental moves:&lt;br /&gt;
&lt;br /&gt;
*Trying not to think of a function in terms of an algorithmic relationship between input and output, e.g. by visualing functions as graphs&lt;br /&gt;
*Having available examples of input-output relationsships which can be described as functions but not algorithmically (e.g. random processes in the stock market)&lt;br /&gt;
&lt;br /&gt;
==Available resources==&lt;br /&gt;
Researchers have developed teaching materials to help students overcome conceptual difficulties with functions, see in particular the text books by Arnon et. al.&amp;lt;ref name=&amp;quot;:0&amp;quot; /&amp;gt; and Dubinsky et al.&amp;lt;ref&amp;gt;Dubinsky, E., Schwingendorf, K. E., &amp;amp; Mathews, D. M.: &amp;#039;&amp;#039;Calculus concepts and computers&amp;#039;&amp;#039; (2nd ed.). McGraw-Hill College 1994, [https://de.wikipedia.org/wiki/Spezial:ISBN-Suche/9780314011299 ISBN 978-0-314-01129-9]&amp;lt;/ref&amp;gt;&lt;br /&gt;
&lt;br /&gt;
==References==&lt;br /&gt;
&lt;br /&gt;
[[Category:Decoding work]]&lt;br /&gt;
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		<author><name>Riegler</name></author>
	</entry>
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