* 在新的练习会话中从包根运行；只读模拟CSV，不联网或安装命令。
* clear all 会清空该会话；replace 覆写包内同名成果，先保存已有工作。
version 17
clear all
set more off
capture log close
log using "stata.log", text replace
import delimited "results/simulated-data.csv", clear varnames(1) asdouble
assert _N == 500
assert !missing(x,y)
file open output using "stata-estimates.csv", write replace
file write output "variance,term,n,coefficient,standard_error,ci_lower,ci_upper,p_value" _n
foreach variance in conventional HC1 {
    if "`variance'" == "conventional" {
        regress y x
    }
    else {
        regress y x, vce(robust)
    }
    foreach term in _cons x {
        scalar low = _b[`term'] - invttail(e(df_r),.025)*_se[`term']
        scalar high = _b[`term'] + invttail(e(df_r),.025)*_se[`term']
        scalar pval = 2*ttail(e(df_r),abs(_b[`term']/_se[`term']))
        local label = cond("`term'"=="_cons","intercept","x")
        file write output "`variance',`label'," %12.0f (e(N)) "," %21.15g (_b[`term']) "," %21.15g (_se[`term']) "," %21.15g (low) "," %21.15g (high) "," %21.15g (pval) _n
    }
}
file close output
display "ROBUST_STATA_COMPLETED"
log close