/*STATA PROGRAM FOR CHOICE EXPERIMENT EXAMPLE */

#delimit ;

set mem 30m;
set matsize 800;
set more off;
set logtype text;

log using c:\Klaus\apec64\spring_07\stata\logs\ce_example, replace;

/* add baseline categories */
/*use c:\klaus\apec64\spring_07\stata\data\maine_forest;
gen dead0=0;
recode dead0 0=1 if dead10==0 & dead5==0;
label var dead0 "1=no dead trees left after harvest";
gen live0=0;
recode live0 0=1 if live153==0 & live459==0;
label var live0 "1=no live trees left after harvest";
gen hopen5=0;
recode hopen5 0=1 if hopen35==0 & hopen125==0;
label var hopen5 "1=max size of harvest openings < 35 acres";
gen perh20=0;
recode perh20 0=1 if perh80==0 & perh50==0;
label var perh20 "1=20% of forest or less protected";
gen lvslash=0;
recode lvslash 0=1 if remslash==0 & dstslash==0;
label var lvslash "1=leave slash in place or piles";
save c:\klaus\apec64\spring_07\stata\data\ce_example;*/

use c:\klaus\apec64\spring_07\stata\data\ce_example;

/*********************************************************************/
/* Run model with baseline categories = least environmentally friendly harvesting */
/********************************************************************/

clogit  choice dead5 dead10 live153 live459 hopen35 hopen5 perh50 perh20 dstslash lvslash tax, group(id);

nlcom -(_b[dead5]/_b[tax]);
nlcom -(_b[dead10]/_b[tax]);
nlcom -(_b[live153]/_b[tax]);
nlcom -(_b[live459]/_b[tax]);
nlcom -(_b[hopen35]/_b[tax]);
nlcom -(_b[hopen5]/_b[tax]);
nlcom -(_b[perh50]/_b[tax]);
nlcom -(_b[perh20]/_b[tax]);
nlcom -(_b[dstslash]/_b[tax]);
nlcom -(_b[lvslash]/_b[tax]);

/* Marginal Effects */
/********************/
predict phat;

/* test if add to one*/
sort runid;
egen p_sum=sum(phat), by(id);
tab p_sum;

/* hit rates */
egen hit=max(phat), by (id);
recode hit *=1 if hit==phat;
recode hit *=0 if hit<1;
label var hit "predicted choice";
tab choice hit;

/* marginal own-effects */
gen p_term=phat*(1-phat);
gen m_dead5=p_term*_b[dead5];
gen m_dead10=p_term*_b[dead10];
gen m_live153=p_term*_b[live153];
gen m_live459=p_term*_b[live459];

sum m_*;


/*********************************************************************/
/* Run model with baseline categories = most environmentally friendly harvesting */
/********************************************************************/

clogit  choice dead5 dead0 live153 live0 hopen35 hopen125 perh50 perh80 dstslash remslash tax, group(id);

nlcom -(_b[dead5]/_b[tax]);
nlcom -(_b[dead0]/_b[tax]);
nlcom -(_b[live153]/_b[tax]);
nlcom -(_b[live0]/_b[tax]);
nlcom -(_b[hopen35]/_b[tax]);
nlcom -(_b[hopen125]/_b[tax]);
nlcom -(_b[perh50]/_b[tax]);
nlcom -(_b[perh80]/_b[tax]);
nlcom -(_b[dstslash]/_b[tax]);
nlcom -(_b[remslash]/_b[tax]);










log close;