Hi,

I'm studying bootstrap for microarray analysis. I found this code from http://www.compgen.org/tools/microarrays

Code:
program define ttestboot, rclass
version 10.1
    syntax , x(varlist numeric max=1) type(varlist numeric max=1) [ reps(real 100) var(string )  ]
set more off

di in ye "______________________________________________________________________________"

di in ye "   Calculation of Achieved Significance Level (ASL) using the bootstrap"
di in ye "   The idea is to recenter the two samples to the combined sample mean"
di in ye "   so that the data now conform to the null hypothesis but that the"
di in ye "   variances within the samples remain unchanged"
di in ye "______________________________________________________________________________"

preserve
ttest `x',by(`type') uneq
tempname tobs omean
scalar `tobs' = r(t)
qui summarize `x', meanonly
scalar `omean' = r(mean)
qui summarize `x' if `type'==0, meanonly
qui replace `x' = `x' - r(mean) + scalar(`omean') if `type'==0
qui summarize `x' if `type'==1, meanonly
qui replace `x' = `x' - r(mean) + scalar(`omean') if `type'==1
tempfile boot

bootstrap t=r(t),nolegend nowarn notable reps(`reps') strata(`type') saving(`boot'): ttest `x',by(`type') `var'

use `boot',clear
qui generate indicator = abs(t)>=abs(scalar(`tobs'))
qui summarize indicator, meanonly
display in ye "ASLboot = " r(mean)
restore
return scalar p=r(mean)
end
I have a gene expression data which has 10 Treatment and 10 control samples with 250 genes. I converted it vectorized format. For example:
Gene Exp Type
Gene1 1.602014 1=treat
Gene1 1.497501 0=control
Gene2 1.675608 1
Gene2 3.727904 0
When I run this code for this table I 'm getting this error:



Code:
ttestboot Expr Type [reps(100) Gene]
#varlist not allowed
I guess I don't know and understand calling program. I described list object with this command:

Code:
list Expr Type Gene
How can I call ttestboot ? Can you suggest something or share knowledge?