topic Method for calculation of degrees of freedom? in Discussions https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7622#M7616 <HTML><HEAD></HEAD><BODY><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;">Hi!</SPAN></P><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;"><BR /></SPAN></P><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;">I was wondering if anyone knows how JMP calculate degrees of freedom? I think SAS is using the <SPAN lang="EN-US" style="font-family: Helvetica; color: black;">Satterhwaite approximation, but I cannot find any information about if JMP use the same?</SPAN><BR /></SPAN></P><P></P><P><SPAN style="font-size: 10pt;">Thanks! </SPAN></P></BODY></HTML> Fri, 18 Oct 2013 08:23:01 GMT sandra_chiriac 2013-10-18T08:23:01Z Method for calculation of degrees of freedom? https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7622#M7616 <HTML><HEAD></HEAD><BODY><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;">Hi!</SPAN></P><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;"><BR /></SPAN></P><P><SPAN lang="EN-US" style="font-size: 10pt; font-family: Helvetica; color: black;">I was wondering if anyone knows how JMP calculate degrees of freedom? I think SAS is using the <SPAN lang="EN-US" style="font-family: Helvetica; color: black;">Satterhwaite approximation, but I cannot find any information about if JMP use the same?</SPAN><BR /></SPAN></P><P></P><P><SPAN style="font-size: 10pt;">Thanks! </SPAN></P></BODY></HTML> Fri, 18 Oct 2013 08:23:01 GMT https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7622#M7616 sandra_chiriac 2013-10-18T08:23:01Z Re: Method for calculation of degrees of freedom? https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7623#M7617 <HTML><HEAD></HEAD><BODY><P>Hi Sandra,</P><P></P><P>Which JMP platform are you looking at?</P><P></P><P>If it's Fit Model, which personality are you using?</P><P></P><P>-Jeff</P></BODY></HTML> Thu, 24 Oct 2013 00:38:22 GMT https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7623#M7617 Jeff_Perkinson 2013-10-24T00:38:22Z Re: Method for calculation of degrees of freedom? https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7624#M7618 <HTML><HEAD></HEAD><BODY><P>I am working in JMP 9.0. </P><P></P><P>I just open my data table, then go to analyze - fit model. In the box that opens, I specify the different parameters: </P><P>1) <SPAN style="font-size: 10pt; line-height: 1.5em;">the dependent variable in Y below "Pick Role Variables"</SPAN></P><P><SPAN style="font-size: 10pt; line-height: 1.5em;">2) and other variables below "construct model effects". These are both continuous and nominals, one is random and there are at least 2 interactions included in the original model.</SPAN></P><P></P><P>The other settings I use are:</P><P>Personality: Standrad Least Squares</P><P>Emphasis: Minimal Report</P><P>Method: REML (Recommended)</P><P></P><P>Unbound Variance Component are also used.</P><P></P><P>Thanks in advance!</P><P></P><P>/Sandra</P></BODY></HTML> Tue, 29 Oct 2013 12:07:56 GMT https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7624#M7618 sandra_chiriac 2013-10-29T12:07:56Z Re: Method for calculation of degrees of freedom? https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7625#M7619 <HTML><HEAD></HEAD><BODY><P>Hi Sandra,</P><P></P><P>From Chapter 7 of <A href="http://www.jmp.com/support/downloads/pdf/jmp11/Fitting_Linear_Models.pdf">Fitting Linear Models</A>:</P><P></P><DIV class="column"><P><SPAN style="font-size: 10.000000pt; font-family: 'HelveticaNeue'; font-weight: bold; color: rgb(50.196000%, 0.000000%, 50.196000%);">Degrees of Freedom </SPAN></P><P><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">The degrees of freedom for tests involving only linear combinations of fixed effect parameters are calculated using the first</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">‐</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">order Kenward and Roger correction. So JMP’s results for these tests match PROC MIXED using the DDFM=KENWARDROGER(FIRSTORDER) option. If there are BLUPs in the linear combination, JMP uses a Satterthwaite approximation to get the degrees of freedom. The results then follow a pattern similar to what is described for standard errors in the preceding paragraph. </SPAN></P><P><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);"><BR /></SPAN></P><P><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">For more details about the Kackar</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">‐</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">Harville correction and the Kenward</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">‐</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">Roger DF approach, see Kenward and Roger (1997). The Satterthwaite method is described in detail in the SAS PROC MIXED documentation (</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; font-style: italic; color: rgb(50.196000%, 0.000000%, 50.196000%);">SAS/STAT 9.2 User’s Guide</SPAN><SPAN style="font-size: 10.000000pt; font-family: 'PalatinoLinotype'; color: rgb(50.196000%, 0.000000%, 50.196000%);">, Chapter 56). </SPAN></P></DIV><P></P><P>-Jeff</P></BODY></HTML> Tue, 29 Oct 2013 13:42:21 GMT https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7625#M7619 Jeff_Perkinson 2013-10-29T13:42:21Z Re: Method for calculation of degrees of freedom? https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7626#M7620 <HTML><HEAD></HEAD><BODY><P>Ok, thank you for you help!</P><P></P><P>/Sandra</P></BODY></HTML> Tue, 29 Oct 2013 14:30:17 GMT https://community.jmp.com/t5/Discussions/Method-for-calculation-of-degrees-of-freedom/m-p/7626#M7620 sandra_chiriac 2013-10-29T14:30:17Z