*! Version 3.2 27May2007 ************************************************************************************************************ * Traces: Traces of items * Version 3.2: May 27, 2007 (onlyone option) * * Historic: * Version 1 (2003-06-29): Jean-Benoit Hardouin * Version 2 (2003-07-04): Jean-Benoit Hardouin * version 3 (2003-07-09): Jean-Benoit Hardouin * Version 3.1 (2005-06-07): Jean-Benoit Hardouin /*small modifications*/ * * Jean-benoit Hardouin, phD, Assistant Professor * Team of Biostatistics, Clinical Research and Subjective Measures in Health Sciences * University of Nantes - Faculty of Pharmaceutical Sciences * France * jean-benoit.hardouin@anaqol.org * * News about this program :http://www.anaqol.org * FreeIRT Project website : http://www.freeirt.org * * Copyright 2003, 2005, 2007 Jean-Benoit Hardouin * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * ************************************************************************************************************ program define traces version 8.0 syntax varlist(numeric min=2) [, Score Test Restscore Logistic CI CUMulative REPFiles(string) SCOREFiles(string) RESTSCOREFiles(string) LOGISTICFile(string) noDraw noDRAWComb REPlace ONLYone(string) THResholds(string)] local nbitems : word count `varlist' tokenize `varlist' if "`onlyone'"!=""&"`drawcomb'"!="" { local drawcomb } tempvar varscore qui gen `varscore'=0 label variable `varscore' "Total score" local scoremax=0 local flag=0 if "`score'"==""&"`restscore'"==""&&"`logistic'"=="" { local score="score" } forvalues i=1/`nbitems' { qui replace `varscore'=`varscore'+``i'' qui su ``i'' local modamax`i'=r(max) if r(min)!=0 { local flag=1 } local scoremax=`scoremax'+`modamax`i'' if `modamax`i''!=1 { local flagbin=0 } } if `flag'==1 { di as error "The lower modality of the item must be 0" exit } if "`flagbin'"!=""&"`logistic'"!="" { di as error "The logistic option is not possible with polytomous items" exit } qui su `varscore' local maxscore=r(max) forvalues i=0/`maxscore' { qui count if `varscore'==`i' local nscore`i'=r(N) } global score global restscore global logistic if "`score'"!="" { if "`thresholds'"!="" { * set trace on local nbth:word count `thresholds' forvalues t=1/`nbth' { local th`t':word `t' of `thresholds' } tempname label local recode 0/`th1'=1 `=`th`nbth''+1'/max=`=`nbth'+1' qui label define `label' 1 "0/`th1'",add qui label define `label' `=`nbth'+1' "`=`th`nbth''+1'/max",add forvalues j=2/`nbth' { local recode `recode' `=`th`=`j'-1''+1'/`th`j''=`j' qui label define `label' `j' "`=`th`=`j'-1''+1'/`th`j''",add } tempname varscore2 qui gen `varscore2'=`varscore' qui recode `varscore' `recode' qui label values `varscore' `label' local nbgroups=`nbth'+1 local minimum=1 } else { local nbgroups=`maxscore' local minimum=0 } forvalues i=1/`nbitems' { local y`i' forvalues k=1/`modamax`i'' { tempvar propscore`i'`k' tmp if "`cumulative'"!="" { qui gen `tmp'=``i''>=`k'&``i''!=. bysort `varscore' : egen `propscore`i'`k''=mean(`tmp') label variable `propscore`i'`k'' "Item ``i''>=`k'" } else { qui gen `tmp'=``i''==`k'&``i''!=. bysort `varscore' : egen `propscore`i'`k''=mean(`tmp') label variable `propscore`i'`k'' "Item ``i''=`k'" } local y`i'="`y`i'' `propscore`i'`k''" local style="solid" local color="black" local width="medthick" if `modamax`i''==1&"`ci'"!="" { tempvar icscoreminus icscoreplus forvalues l=1/`maxscore' { qui count if `varscore'==`l' local nscore`l'=r(N) } qui gen `icscoreminus'=`propscore`i'1'-1.96*sqrt(`propscore`i'1'*(1-`propscore`i'1')/`nscore1') qui gen `icscoreplus'=`propscore`i'1'+1.96*sqrt(`propscore`i'1'*(1-`propscore`i'1')/`nscore1') label variable `icscoreminus' "Lower 95% confidence interval" label variable `icscoreplus' "Upper 95% confidence interval" local y`i'="`icscoreminus' `icscoreplus' `propscore`i'1'" local style="dash dash solid" local color="red red black" local width="thin thin medthick" } if `modamax`i''==1&"`test'"!="" { qui regress `propscore`i'1' `varscore' local p=Fden(e(df_m),e(df_r),e(F)) if `p'<0.0001 { local note="Test: slope=0, p<0.0001" } else { local p=substr("`p'",1,6) local note="Test: slope=0, p=`p'" } } } if "``i''"=="`onlyone'"|"`onlyone'"=="" { qui graph twoway (line `y`i'' `varscore', clpattern(`style') clcolor(`color') clwidth(`width')) if `varscore'!=0&`varscore'!=`maxscore' , note("`note'") ylabel(0(.25)1) xlabel(`minimum'(1)`nbgroups',valuelabel) name(score`i',replace) title("Trace of the item ``i'' as a function of the score") ytitle("Rate of positive response") `draw' } global score "$score score`i'" if "`scorefiles'"!="" { graph save score`i' `repfiles'\\`scorefiles'``i'' ,`replace' } } if "`thresholds'"!="" { qui replace `varscore'=`varscore2' } } if "`restscore'"!="" { forvalues i=1/`nbitems' { local y`i' tempvar restscore`i' qui gen `restscore`i''=`varscore'-``i'' label variable `restscore`i'' "Rest score with respect to the item ``i''" if "`thresholds'"!="" { * set trace on local nbth:word count `thresholds' forvalues t=1/`nbth' { local th`t':word `t' of `thresholds' } tempname label local recode 0/`th1'=1 `=`th`nbth''+1'/max=`=`nbth'+1' qui label define `label' 1 "0/`th1'",add qui label define `label' `=`nbth'+1' "`=`th`nbth''+1'/max",add forvalues j=2/`nbth' { local recode `recode' `=`th`=`j'-1''+1'/`th`j''=`j' qui label define `label' `j' "`=`th`=`j'-1''+1'/`th`j''",add } *di "recode `restscore`i'' `recode'" qui recode `restscore`i'' `recode' qui label values `restscore`i'' `label' local nbgroups=`nbth'+1 local minimum=1 } else { local nbgroups=`maxscore' local minimum=0 } forvalues k=1/`modamax`i'' { tempvar rtmp proprestscore`i'`k' if "`cumulative'"!="" { qui gen `rtmp'=``i''>=`k'&``i''!=. bysort `restscore`i'': egen `proprestscore`i'`k''=mean(`rtmp') label variable `proprestscore`i'`k'' "Item ``i''>=`k'" } else { qui gen `rtmp'=``i''==`k'&``i''!=. bysort `restscore`i'': egen `proprestscore`i'`k''=mean(`rtmp') label variable `proprestscore`i'`k'' "Item ``i''=`k'" } local y`i'="`y`i'' `proprestscore`i'`k''" local style="solid" local color="black" local width="medthick" if `modamax`i''==1&"`ci'"!="" { tempvar icrestscoreminus icrestscoreplus qui su `restscore`i'' local maxrestscore=r(max) forvalues l=1/`maxrestscore' { qui count if `restscore`i''==`l' local nrestscore`i'=r(N) } qui gen `icrestscoreminus'=`proprestscore`i'1'-1.96*sqrt(`proprestscore`i'1'*(1-`proprestscore`i'1')/`nrestscore`i'') qui gen `icrestscoreplus'=`proprestscore`i'1'+1.96*sqrt(`proprestscore`i'1'*(1-`proprestscore`i'1')/`nrestscore`i'') label variable `icrestscoreminus' "Lower 95% confidence interval" label variable `icrestscoreplus' "Upper 95% confidence interval" local y`i'="`icrestscoreminus' `icrestscoreplus' `proprestscore`i'1'" local style="dash dash solid" local color="red red black" local width="thin thin medthick" } if `modamax`i''==1&"`test'"!="" { qui regress `proprestscore`i'1' `varscore' local p=Fden(e(df_m),e(df_r),e(F)) if `p'<0.0001 { local note="Test: slope=0, p<0.0001" } else { local p=substr("`p'",1,6) local note="Test: slope=0, p=`p'" } } } local restscoremax=`scoremax'-`modamax`i'' if "``i''"=="`onlyone'"|"`onlyone'"=="" { *tab `proprestscore`i'1' `restscore`i'' qui graph twoway (line `y`i'' `restscore`i'', clpattern(`style') clcolor(`color') clwidth(`width')), note("`note'") ylabel(0(0.25)1) xlabel(`minimum'(1)`nbgroups',valuelabel) name(restscore`i',replace) title("Trace of the item ``i'' as a function of the restscore") ytitle("Rate of positive response") `draw' } global restscore "$restscore restscore`i'" if "`restscorefiles'"!="" { graph save restscore`i' `repfiles'\\`restscorefiles'``i'' ,`replace' } } } if "logistic"!="" { forvalues i=1/`nbitems' { qui logistic ``i'' `varscore' tempname coef matrix `coef'=e(b) local pente`i'=`coef'[1,1] local intercept`i'=`coef'[1,2] tempvar logit`i' qui gen `logit`i''=exp(`intercept`i''+`pente`i''*`varscore')/(1+exp(`intercept`i''+`pente`i''*`varscore')) label variable `logit`i'' "Item ``i''" sort `varscore' global logistic "$logistic `logit`i''" } } if "`drawcomb'"!="" { local drawcomb="nodraw" } if "`score'"!=""&"`onlyone'"=="" { graph combine $score , title("Trace of the items as a function of the score") name(score,replace) `drawcomb' if "`scorefiles'"!="" { graph save score `repfiles'\\`scorefiles' ,`replace' } } if "`restscore'"!=""&"`onlyone'"=="" { graph combine $restscore , title("Trace of the items as a function of the restscores") name(restscore,replace) `drawcomb' if "`restscorefiles'"!="" { graph save restscore `repfiles'\\`restscorefiles' ,`replace' } } if "`logistic'"!="" { graph twoway (line $logistic `varscore'), ylabel(0(0.25)1) xlabel(0(1)`nbitems') title("Logistic traces") ytitle("") name(logistic,replace) `drawcomb' if "`logisticfile'"!="" { graph save logistic `repfiles'\\`logisticfile' ,`replace' } } end