区别是需要看帮助，但是非官方命令，如果作者不提供详细信息就很难判断，如：vartable

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Title

    [TS] dfuller -- Augmented Dickey-Fuller unit-root test


Syntax

        dfuller varname [if] [in] [, options]

    options         Description
    --------------------------------------------------------------------------------------
    Main
      noconstant    suppress constant term in regression
      trend         include trend term in regression
      drift         include drift term in regression
      regress       display regression table
      lags(#)       include # lagged differences
    --------------------------------------------------------------------------------------
    You must tsset your data before using dfuller; see [TS] tsset.
    varname may contain time-series operators; see tsvarlist.


Menu

    Statistics > Time series > Tests > Augmented Dickey-Fuller unit-root test


Description

    dfuller performs the augmented Dickey-Fuller test that a variable follows a unit-root
    process.  The null hypothesis is that the variable contains a unit root, and the
    alternative is that the variable was generated by a stationary process.  You may
    optionally exclude the constant, include a trend term, and include lagged values of
    the difference of the variable in the regression.




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help for vartable
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Cell means, variances & standard deviations
-------------------------------------------

vartable dependent iv1 [iv2 iv3 iv4] [if exp] [in range]


Description
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vartable displays a table of cell means, variances & standard deviations.


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谢谢！