Re: st: tabstatmat question

["Alvarez,Sergio" <sergioal@ufl.edu>]

Sorry about ambiguity.

So I used the mean by group code to create the matrix that would store 
the mean values for each group, using:

egen byv=group(zone wave), lab
tabstat num_typ3, stat(mean) by(byv) save
tabstatmat TABLE

which gives me a matrix, or rather a vector, with all the values I 
need.  The first few lines of the matrix in the output screen look like 
this:

TABLE[414,1]
             num_typ3
  1†1:mean  1.9822335
  1†2:mean  2.6614173
  1†3:mean  2.7150396
  1†4:mean  3.3340782
  1†5:mean  2.8161094
  1†6:mean  1.1767857
  2†1:mean  1.5857143
  2†2:mean  2.1863208
  2†3:mean   2.542777
  2†4:mean  1.8849432

Now what I want to do is use -gen- or -egen- to create a variable that 
would look up the zone and wave of the corresponding observation from 
the matrix and insert the correct value in there.  So I tried:

gen meancatch = TABLE[zone,wave]

and this gives the correct values for all observations with wave = 1, 
but creates missing values on the rest of the observations.  I also 
tried:

gen meancatch = TABLE[byv,num_typ3]

and this gives me the correct value in some of the observations, but 
mostly missing values in the others.

So I must be doing something wrong, but can't figure out what.  I guess 
the question is how to call the row and column numbers from the TABLE 
matrix?

Thanks again,

Sergio


On Fri, 2 Sep 2011 12:08:31 -0400, Austin Nichols wrote:
> Sergio <sergioal@ufl.edu> :
> Now I have no idea what you are trying to do. For the mean by group,
> egen mby=mean(num_typ3), by(zone wave)
> but you are referring to (probably) nonexistent row and column 
> numbers
> of a matrix in your example.
>
> On Fri, Sep 2, 2011 at 10:42 AM, Alvarez,Sergio <sergioal@ufl.edu> 
> wrote:
> > Thanks Austin and Nick for your help.  I used what Austin suggested 
> > (which
> > is what Nick also suggested) and it worked. However, when I try to 
> > create
> > the variable that contains the mean by group it works for some 
> > observations,
> > but missing values are created for most of them.  I tried both:
> >
> > gen meancatch = TABLE[zone,wave]
> > and
> > gen meancatch = TABLE[byv,num_typ3]
> >
> > For the first line of code, it creates the correct value for all
> > observations where wave = 1, but not for any others.  The second 
> > line
> > creates missing values at random (as far as I can tell).
> >
> > I'd appreciate any tips.
>
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--
Sergio Alvarez
Food and Resource Economics
University of Florida
*
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