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   tstat specifies that t-statistics rather than standard errors are reported. The decimal places
        displayed are set by auto

    pvalue specifies that p-values (of t-statistics) rather than standard errors are reported. The
        decimal places displayed are set by tdec.

    ci specifies that confidence intervals of coefficients rather than standard error are reported.
        The decimal places displayed are those set by bdec.
   
    level(integer) specifies the confidence level, in percent, for confidence intervals. The default
        is level(95) or as set by set level, see [U] Specifying the width of confidence intervals.
        level does not affect the confidence levels of asterisks.
   
    beta asks that normalized beta coefficients be reported rather than standard errors (see the beta
        option of regress). The decimal places displayed are those set by bdec.

    nocons specifies that the intercept (constant) coefficient estimate not be reported. This is not
        needed when the preceeding estimation has no intercept coefficient.

    noni specifies that the number of groups in a panel data regression not be reported (e.g. the
        number of groups specified by the i( ) variable in xtreg). This option has an effect only
        after xt regression commands.

outreg2 using myfile,tstat e(r2_a,F) bdec(3) tdec(2)

谢谢哈，刚好用上了

e(r2_a,F)是设置什么

adjusted r-square and F statistics