st: How to test ratio of coefficients

["George_Huang" <cjhuang168@gmail.com>]

Hi,

I have following regression:

reg y x1 x2 x3 x4 x1Xx3 x1Xx4 x2Xx3 x2Xx4

I would like to compare ratio of coefficients on x1Xx3 / x1Xx4 with the 
following ratio:  x2Xx3 / x2Xx4.
I try to use the following commend:

test x1Xx3 / x1Xx4 = x2Xx3 / x2Xx4

However, I got the result stated “not possible with test”. Are there other 
ways to solve the problem?
Any suggestion is greatly appreciated.

Best,

George





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