st: calculation of firm selection probability weight

[Prakash Singh <prakashbhu@gmail.com>]

Dear all

Please pardon me as I feel I am asking very basic question.I have two
questions to ask.

First, I am working with cross country firm level survey data. in the
survey data number of firm are varying country to country, industry to
industry, to reduce the effect of  uneven number of firms in the
pooled regression data I would like to run the regression with weight,
equal to the the inverse of the probability of being included in a
specfic country sample.

My question is how to calculate this probability of firm selection.

My second question is in the context of same cross country firm level
survey data
I want to generate variable X using Y such that Y is divided by sum of
Y at country level as well as industry level.

something like

gen X=Y/sum(Y) by (country industry)


Thanks in advance



Prakash

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