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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Dear Tanmay,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">For this type of question, the yahoo discussion list for Siena/Stocnet<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">http://groups.yahoo.com/groups/stocnet/<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Is more appropriate (the yahoo list is meant for discussions between users, this list is for discussions between programmers).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">But let me answer this here. The NA standard errors are given in case of parameter collinearity. In this case they mean that you have included a set of effects
that together are linearly dependent: some linear combination of them has infinite standard error.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I suggest that you retain only one of the GWESP effects, and test the other three by a score-type test (manual section 8.2), and include them only (one by one
in successive model fits) if from the score test it can be concluded that they are significant.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Best wishes,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Tom<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">================================================================<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Tom A.B. Snijders<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Professor of Statistics and Methodology<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Dept. of Sociology, University of Groningen<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Emeritus Fellow, Nuffield College, University of Oxford<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Associate Member, Dept. of Statistics, University of Oxford<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">http://www.stats.ox.ac.uk/~snijders/<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> rsiena-help-bounces@lists.r-forge.r-project.org [mailto:rsiena-help-bounces@lists.r-forge.r-project.org]
<b>On Behalf Of </b>tanmay sinha<br>
<b>Sent:</b> 15 April 2015 16:45<br>
<b>To:</b> rsiena-help@lists.r-forge.r-project.org<br>
<b>Subject:</b> [Rsiena-help] What does NA for standard errors mean?<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi all, I am a new user to RSiena. After running the model that includes certain structural configurations, I find that some of my standard errors are NA.<o:p></o:p></p>
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<p class="MsoNormal">I include a portion of the output, with the 3 columns representing estimates, standard errors and t-ratios. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> 8. eval GWESP I -> K -> J (69) 2.1135 ( NA ) -0.7091 <o:p></o:p></p>
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<p class="MsoNormal"> 9. eval GWESP I <- K <- J (69) 0.1239 ( NA ) -0.1293 <o:p></o:p></p>
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<p class="MsoNormal"> 10. eval GWESP I <- K -> J (69) -0.4884 ( NA ) -0.0660 <o:p></o:p></p>
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<p class="MsoNormal"> 11. eval GWESP I -> K <- J (69) -0.4797 ( NA ) -0.1918 <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">What do the NA mean?? How do I interpret this?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I would greatly appreciate your help.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards<o:p></o:p></p>
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<p class="MsoNormal">Tanmay Sinha<o:p></o:p></p>
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