https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603820#M80678 <P>Hi <a href="https://community.jmp.com/t5/user/viewprofilepage/user-id/46787">@KDan</a>,</P> <P>Very glad to know you're using our SEM platform! A couple things to clarify:</P> <P>There is a <U><STRONG>by-group analysis</STRONG></U> option:</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_0-1677075950841.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50327iDDB22BFF59A65A58/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_0-1677075950841.png" alt="LauraCS_0-1677075950841.png" /></span></P> <P>&nbsp;</P> <P>And also a <U><STRONG>multiple-group analysis</STRONG></U> option:</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_1-1677076043270.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50330i9D65CBD13CC0EA99/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_1-1677076043270.png" alt="LauraCS_1-1677076043270.png" /></span></P> <P>&nbsp;</P> <P>My guess is you want to do multiple-group analysis (MGA). Is this correct? With MGA, you're able to use your full sample and test for group differences in parameters across groups, whereas the By-group option simply expedites the fitting of two separate models (one for each group), which effectively divides your sample size in two (or more depending on how many levels your grouping variable has).</P> <P>&nbsp;</P> <P>The sample size error shows up when your sample size is smaller than the number of parameters you're trying to estimate (side note: you can get a description of the warning/error by clicking on it in the Status tab):</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_2-1677076630647.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50338iB2CE3CDF294D2F7B/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_2-1677076630647.png" alt="LauraCS_2-1677076630647.png" /></span></P> <P>Thus, the only way around this warning is (1) using a larger sample size or (2) reducing the number of estimates in your model. Are you able to specify a more parsimonious model?</P> <P>Lastly, if you accidentally used the by-group option, that could lead to the sample size warning because your sample is being divided to achieve separate models for each of the levels of the grouping variable, so just switching to MGA might solve the problem.</P> <P>&nbsp;</P> <P>HTH,</P> <P>~Laura</P> Wed, 22 Feb 2023 14:37:40 GMT LauraCS 2023-02-22T14:37:40Z https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603768#M80673 <P>Hello, I am running a by-group SEM on JMP Pro 17. In the Identification Rules, I am getting a model error for the sample size rule. Is there any way around this so I can still run this model? Thank you!</P> Thu, 08 Jun 2023 16:34:17 GMT https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603768#M80673 KDan 2023-06-08T16:34:17Z https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603820#M80678 <P>Hi <a href="https://community.jmp.com/t5/user/viewprofilepage/user-id/46787">@KDan</a>,</P> <P>Very glad to know you're using our SEM platform! A couple things to clarify:</P> <P>There is a <U><STRONG>by-group analysis</STRONG></U> option:</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_0-1677075950841.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50327iDDB22BFF59A65A58/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_0-1677075950841.png" alt="LauraCS_0-1677075950841.png" /></span></P> <P>&nbsp;</P> <P>And also a <U><STRONG>multiple-group analysis</STRONG></U> option:</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_1-1677076043270.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50330i9D65CBD13CC0EA99/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_1-1677076043270.png" alt="LauraCS_1-1677076043270.png" /></span></P> <P>&nbsp;</P> <P>My guess is you want to do multiple-group analysis (MGA). Is this correct? With MGA, you're able to use your full sample and test for group differences in parameters across groups, whereas the By-group option simply expedites the fitting of two separate models (one for each group), which effectively divides your sample size in two (or more depending on how many levels your grouping variable has).</P> <P>&nbsp;</P> <P>The sample size error shows up when your sample size is smaller than the number of parameters you're trying to estimate (side note: you can get a description of the warning/error by clicking on it in the Status tab):</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LauraCS_2-1677076630647.png" style="width: 400px;"><img src="https://community.jmp.com/t5/image/serverpage/image-id/50338iB2CE3CDF294D2F7B/image-size/medium?v=v2&amp;px=400" role="button" title="LauraCS_2-1677076630647.png" alt="LauraCS_2-1677076630647.png" /></span></P> <P>Thus, the only way around this warning is (1) using a larger sample size or (2) reducing the number of estimates in your model. Are you able to specify a more parsimonious model?</P> <P>Lastly, if you accidentally used the by-group option, that could lead to the sample size warning because your sample is being divided to achieve separate models for each of the levels of the grouping variable, so just switching to MGA might solve the problem.</P> <P>&nbsp;</P> <P>HTH,</P> <P>~Laura</P> Wed, 22 Feb 2023 14:37:40 GMT https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603820#M80678 LauraCS 2023-02-22T14:37:40Z https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603872#M80681 <P>Thank you very much, this clarifies things!&nbsp;</P><P>Side note: your demonstration videos for SEM on JMP User Community have been EXTREMELY helpful as I navigate this analysis. THANK YOU!</P> Wed, 22 Feb 2023 15:26:08 GMT https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603872#M80681 KDan 2023-02-22T15:26:08Z https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603901#M80685 <P>SO glad to hear!! =)</img></P> <P>~Laura</P> Wed, 22 Feb 2023 16:08:51 GMT https://community.jmp.com/t5/Discussions/JMP-17-Pro-Structural-Equation-Modeling/m-p/603901#M80685 LauraCS 2023-02-22T16:08:51Z