st: sxpose -not possible; would exceed present limit on number of variables

[R Zhang <r05zhang@gmail.com>]

Hi Statalisters,


My data has 13,458 observation and 21 variables.
EntityID corpid1 begyr1 gvkey1 endyr1 corpid2 begyr2 gvkey2 endyr2
corpid3 begyr3 gvkey3 endyr3 corpid4 begyr4 gvkey4 endyr4 corpid5
begyr5 gvkey5 endyr5
100091 8101 1961 1000 1970 8091 1971 1000 1973 8011 1974 1001 2000
8012 2000 1001 2002 8012 2003 1001 2005


for each unique EntityID, the corresponding gvkey and corpid could
vary over time as indicated by begyr and endyr,

what I want is a dataset that give me the gvkey and corpid for each
time period, so I can match it to another dataset that has company
specific financial data , the match variable will be gvkey, year.

as of now, i thought I should reshape the data, Someone on the forum
kindly offered me the following program to reshape my data. sample
code (see below) works for his hypothetical data, but when i ran with
my data (13,458 observation and 21 variables.). I got an error "not
possible; would exceed present limit on number of variables", could
you shed light on this?

*****************
input str20 v1 v2
EntityID 100091
corpid1 8101
begyr1 1961
gvkey1 1000
endyr1 1970
corpid2 8091
begyr2 1971
gvkey2 1000
endyr2 1973
corpid3 8011
begyr3 1974
gvkey3 1001
endyr3 2000
corpid4 8011
begyr4 1974
gvkey4 1001
endyr4 2000
corpid5 8011
begyr5 1974
gvkey5 1001
endyr5 2000
end

compress
sxpose, clear firstnames force
reshape long corpid begyr gvkey endyr, i(EntityID) j(pd)
***********************

what I ultimately want is :
EntityID corpid year gvkey
100091 8101 1961 1000
100091 8101 1962 1000
100091 8101 1963 1000
100091 8101 1964 1000
100091 8101 1965 1000
100091 8101 1966 1000
…
100091 8091 1971 1000
100091 8091 1972 1000
100091 8091 1973 1000
100091 8091 1974 1000

p.s if you think there is a better way , please also share.

thanks!!!

-R

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