Bookmark and Share

Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

st: design issue

From   "[email protected]" <[email protected]>
To   <[email protected]>
Subject   st: design issue
Date   Fri, 21 Jan 2011 16:06:32 +0100 (CET)

Dear statalist,

I have a research design doubt. 

I am considering the following model and the focus of the analysis is on a2:


where z is a dummy variable

Economic theory also suggests that:


If I find collinearity between x and z to be ok, can I estimate the first 
equation with OLS and disregard the second equation? 

My view is that I can safely use OLS only if cov(e,v)=0, but how can I test 
this condition?

Thanks a lot,


*   For searches and help try:

© Copyright 1996–2018 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   Site index