program define domsvy

version 6.0

#delimit ;

* syntax is domsvy var1 strata1 psu1 wgt1 var2 strata2 psu2 wgt2

zmax #test-points;

local x1 `1';

local str1 `2';

local psu1 `3';

local wgt1 `4';

local x2 `5';

local str2 `6';

local psu2 `7';

local wgt2 `8';

local zmax `9';

local num = `10';

summarize `x1', meanonly;

local min1 = r(min);

summarize `x2', meanonly;

local min2 = r(min);

local min = max(`min1',`min2');

local inter = (`zmax'-`min')/(`num'-1);

local min = `min' + 3*`inter';

local inter = (`zmax'-`min')/(`num'-1);

local done = 0;

local s = 1;

tempvar ind X1 X2;

display " ";

display "Minimum test point is " `min';

display " ";

display "Maximum test point is " `zmax';

display " ";

if `zmax' <= `min' {;

local done = 1;

display " ";

display in red "Error: " in yellow "Max test point is not larger than min test point!";

display " ";

};

while `done' == 0 {;

display " ";

display "Order " `s';

display " Z D1 D2 t-statistic";

local alpha = `s' - 1;

local afac = round(exp(lnfact(`alpha')),1);

local i = 2;

local z = `min';

quietly gen `ind' = .;

while `z' <= `zmax' + 0.0000001 {;

qui gen double `X1' = 0;

qui replace `X1' = (1/`afac')*((`z'-`x1')^`alpha') if `x1'<=`z';

qui svymean `X1' [pw=`wgt1'], strata(`str1') psu(`psu1');

matrix est1 = e(est);

matrix var1 = e(V_db);

local D1 = est1[1,1];

local VD1 = var1[1,1];

qui gen double `X2' = 0;

qui replace `X2' = (1/`afac')*((`z'-`x2')^`alpha') if `x2'<=`z';

qui svymean `X2' [pw=`wgt2'], strata(`str2') psu(`psu2');

matrix est2 = e(est);

matrix var2 = e(V_db);

local D2 = est2[1,1];

local VD2 = var2[1,1];

local t = (`D2'-`D1')/sqrt(`VD1'+`VD2');

display %10.2f `z' " " %8.2f `D1' " " %8.2f `D2' " " %4.2f `t';

local ind0 = 1.5;

if `t' >= 1.96 {; local ind0 = 1; };

if `t' <= -1.96 {; local ind0 = 2; };

qui replace `ind' = `ind0' if _n==`i';

qui drop `X1' `X2';

local z = `z' + `inter';

local i = `i' + 1;

};

summarize `ind', meanonly;

if r(mean) == 1 {; local done = 1;

global Dorder = -`s';

display "";

display "Dominance achieved at order " `s';

local s = 1;};

if r(mean) == 2 {; local done = 1;

global Dorder = `s';

display "";

display "Dominance achieved at order " `s';

local s = 1;};

if `s' >= 3 {; local done = 1;

global Dorder = 0;

display "";

display "Dominance not achieved up to order 3";};

drop `ind';

local s = `s' + 1;

};

#delimit cr;

end

Help file for ^domsvy^

^domsvy^ conducts stochastic dominance tests up to order 3 for independent

samples from household surveys who's sampling designs are complex.

Reference is Davidson & Duclos (1998). Confidence level for rejection

of null that distributions are identical is 95 percent (alpha = 5)

Syntax is: ^domsvy var1 strata1 psu1 weight1^

^var2 strata2 psu2 weight2^

^"max poverty line" "# of test points"^

Note: Note strata, psu (primary sampling unit) and weight variables must

be included.

Note: The ^maximum poverty line^ (e.g. "z") and ^number of test points^

are scalar values.

Example: ^domsvy exp1 str1 psu1 exp2 str2 psu2 wgt1 exp2 wgt2 z 50^

where z is a scalar.