The weights you can make as follows:
*------------- begin example ------------
clear
input cat catid str1 x
1 24 a
1 73 a
1 6 b
2 108 c
2 12 a
3 67 d
4 41 c
4 9 d
4 103 b
4 85 c
end
bys cat : gen w = 1/_N
list
*----------- end example -------------
You can look at the answer by Rajesh for the rest.
Hope this helps,
Maarten
--- "FUKUGAWA, N." <[email protected]> wrote:
> dear all,
> i need to aggregate the data using weight.
>
> table 1
> cat catid x
> 1 24 a
> 1 73 a
> 1 6 b
> 2 108 c
> 2 12 a
> 3 67 d
> 4 41 c
> 4 9 d
> 4 103 b
> 4 85 c
>
> weight is inverse of the number of "catid" within "cat".
> the number of "catid" can be computed as follows.
>
> . bys cat:count
> -> cat = 1
> 3
> -> cat = 2
> 2
> -> cat = 3
> 1
> -> cat = 4
> 4
>
> then table 1 with weight will be as follows.
>
> table 2
> cat catid x w
> 1 24 a .33
> 1 73 a .33
> 1 6 b .33
> 2 108 c .5
> 2 12 a .5
> 3 67 d 1
> 4 41 c .25
> 4 9 d .25
> 4 103 b .25
> 4 85 c .25
>
> finally i need to aggregated the data by x.
>
> table 3
> x freq
> a 1.166 (=.33+.33+.5)
> b .58 (=.33+.25)
> c 1 (=.5+.25+.25)
> d 1.25 (=1+.25)
>
> how can i obtain tables 2 and 3?
> thank you in advance.
> ---
> FUKUGAWA Nobuya, Ph.D.
> [email protected]
> *
> * For searches and help try:
> * http://www.stata.com/support/faqs/res/findit.html
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
___________________________________________________________
Yahoo! Messenger - with free PC-PC calling and photo sharing. http://uk.messenger.yahoo.com
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
