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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=NO-BOK link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I verified that your explanation is correct. Then this is understood<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>behaviour, although not uniform across model types.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks for the explanation.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hans<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> dave fournier [mailto:davef@otter-rsch.com] <br><b>Sent:</b> Friday, December 14, 2012 7:49 PM<br><b>To:</b> developers@admb-project.org<br><b>Cc:</b> Hans J. Skaug<br><b>Subject:</b> Re: [Developers] Random effects without penalties work: should they?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'>On 12-12-14 09:14 AM, Hans J. Skaug wrote:<br><br>Probably because the Hessian is block diagonal. the code does the minimization separately<br>for each separable call. So variables that are never used do not appear in any separable call<br>and never enter into the estimation. If you used one of the RE's in two separable calls it would<br>probably crash.<br><br><o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre>Hi,<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>I have noted that if you define random effects in your model,<o:p></o:p></pre><pre>but do not use them for anything [u(M+1) and u(M+2)) in<o:p></o:p></pre><pre>the attach model] the program runs fine. This<o:p></o:p></pre><pre>used to cause problems, because the Laplace approximation<o:p></o:p></pre><pre>is not well defined.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>My guess is that the reason why this now works is that<o:p></o:p></pre><pre>the effort to avoid the "infinite loop" in the inner problem<o:p></o:p></pre><pre>that was carried out some years ago has introduced <o:p></o:p></pre><pre>some penalty on the random effects.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Maybe the new behaviour is OK, but it means that you are no longer<o:p></o:p></pre><pre>told if you introduce a random effect that is not used for anything.<o:p></o:p></pre><pre>(Probably you did not do this unintentionally.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Mostly I was curious about finding out what has caused the change.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Hans<o:p></o:p></pre><p class=MsoNormal><br><br><br><o:p></o:p></p><pre>_______________________________________________<o:p></o:p></pre><pre>Developers mailing list<o:p></o:p></pre><pre><a href="mailto:Developers@admb-project.org">Developers@admb-project.org</a><o:p></o:p></pre><pre><a href="http://lists.admb-project.org/mailman/listinfo/developers">http://lists.admb-project.org/mailman/listinfo/developers</a><o:p></o:p></pre></blockquote><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>