*! Version 1 19 November 2008 *! Jean-Benoit Hardouin ************************************************************************************************************ * Stata program : guttmax * Research of the maximal number of Guttman Errors for a specific score * * Historic : * Version 1 (November 19, 2008) [Jean-Benoit Hardouin] * * Jean-benoit Hardouin, phD, Assistant Professor * Team of Biostatistics, Clinical Research and Subjective Measures in Health Sciences (UPRES EA 4275) * University of Nantes - Faculty of Pharmaceutical Sciences * France * jean-benoit.hardouin@anaqol.org * * Requiered Stata modules: * -anaoption- (version 1) * -traces- (version 3.2) * -gengroup- (version 1) * * News about this program :http://www.anaqol.org * FreeIRT Project website : http://www.freeirt.org * * Copyright 2008 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 guttmax , rclass version 10 syntax anything [,Score(int 0)] local step:word count `anything' local nbitems=0 forvalues i=1/`step' { local step`i':word `i' of `anything' if `step`i''>`nbitems' { local nbitems=`step`i'' } } di in green "Number of steps: " in ye `step' di in green "Number of items: " in ye `nbitems' di in green "Score: " in ye `score' tempname mate matrix `mate'=J(1,`step',0) local maxstep=0 forvalues i=1/`nbitems' { local nstep`i'=0 forvalues j=1/`step' { if `step`j''==`i' { local ++nstep`i' if `nstep`i''>`maxstep' { local maxstep=`nstep`i'' } } } } tempname calcul matrix `calcul'=J(`nbitems',`maxstep',0) *matrix list `calcul' forvalues i=1/`nbitems' { *di "item `i'" local n=1 forvalues j=1/`step' { if `step`j''==`i' { forvalues s=`n'/`nstep`i'' { matrix `calcul'[`i',`s']=`calcul'[`i',`s']+`j' } local ++n } } forvalues j=2/`nstep`i'' { matrix `calcul'[`i',`j']=`calcul'[`i',`j']/`j' } } *matrix list `calcul' while (`score'>0) { local max=0 forvalues i=1/`nbitems' { local s=min(`score',`nstep`i'') *di "forvalues j=1/`s' {" forvalues j=1/`s' { if `calcul'[`i',`j']>`max' { local maxi=`i' local maxj=`j' local max=`calcul'[`i',`j'] } } } *di "maxi=`maxi' maxj=`maxj'" local d=0 forvalues l=1/`step' { if `step`l''==`maxi'&`mate'[1,`l']==0&`d'<=`maxj' { matrix `mate'[1,`l']=1 local ++d } } forvalues l=1/`maxj' { matrix `calcul'[`maxi',`l']=0 } local score=`score'-`maxj' *matrix list `calcul' } local emax=0 forvalue i=1/`step' { forvalues j=`=`i'+1'/`step' { if `mate'[1,`i']==0&`mate'[1,`j']==1 { local ++emax } } } di in green "Responses profile generating the most important number of Guttman error" matrix list `mate' ,noheader nonames di in green "Max number of Guttman errors : " in ye `emax' return scalar maxegutt =`emax' end