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special-charactersstata

How to generate new variable from stored results: r(mean)?

I am trying to generate a new variable using the stored result r(mean) from the command sum.

I have a continuous variable 'age'. So, sum age g age0=age–r(mean)

The problem is that this gives the error unknown function age–r() r(133);.

Solution

  • Works for me:

    . sysuse auto, clear
(1978 Automobile Data)

. su mpg

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
         mpg |         74     21.2973    5.785503         12         41

. gen mpg0 = mpg - r(mean)

. su mpg0

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
        mpg0 |         74   -4.03e-08    5.785503  -9.297297    19.7027

    Watch for strange characters, i.e. that the minus sign really is a hyphen [sic].