I have been reading this paper by Profs. Siddhartha G. Dastidary & Raymond Fismanz of Columbia University and Tarun Khanna of HBS. It is quite an interesting paer given its relevance today.
This paper looks at the event when NDA was voted out suddenly by UPA in 2004. The former was pro-privatisation and latter not as much given the coalition compulsions as well. So, the authors look at the returns on share prices of these PSU companies which are to be disinvested. The performance is seen in a 4 trading day window from May 13 to May 18 2004.
The authors divide the disinvest companies into 4 types based o a classification made by NDA then:
Mostly Economics 
