Dear Forum,
Does any fellow forum member happen to know if it is possible in Stata to process a poisson regression with non-integer dependent variables, or would a two step model (Heckman) potentially be more advisable?
Background: I am in a process to test the causality between institutional set-up and venture capital (VC) activities in 54 African countries for a time series of 10 years. The dependent variable is number of VC deals in a particular country in a particular year. As there were no VC activities at all in various countries and several years, the value of the dependent variable is zero in more than 50%. To avoid a bias towards zero, OLS regression seems not appropriate. A poisson regression, however, seems to work for integer values only. But if I just use the number of deals without denominating it by the number of inhabitants in a country, the outcome will favor size of a country inappropriately. If I use the dependent variable number of deals/inhabitants, the dependent variable is more accurate, but not an integer figure anymore.
Many thanks indeed,
Stefan
Does any fellow forum member happen to know if it is possible in Stata to process a poisson regression with non-integer dependent variables, or would a two step model (Heckman) potentially be more advisable?
Background: I am in a process to test the causality between institutional set-up and venture capital (VC) activities in 54 African countries for a time series of 10 years. The dependent variable is number of VC deals in a particular country in a particular year. As there were no VC activities at all in various countries and several years, the value of the dependent variable is zero in more than 50%. To avoid a bias towards zero, OLS regression seems not appropriate. A poisson regression, however, seems to work for integer values only. But if I just use the number of deals without denominating it by the number of inhabitants in a country, the outcome will favor size of a country inappropriately. If I use the dependent variable number of deals/inhabitants, the dependent variable is more accurate, but not an integer figure anymore.
Many thanks indeed,
Stefan
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