st: tobit, ordered probit, or just OLS???

["Augusto Pallavicini" <agupalla@hotmail.com>]

Hi all,

I am doing a contingent valuation method about willingness to pay for wind 
energy based on surveys.
I've got only 69 obs,.

The dependent variable is WTP and the values I obtained are 0 2.5 5 7.5 10 
15. The original question from which I obtained the data was.. Would you be 
willing to pay 2.5 pounds for...? If yes, would you be willing to pay 5...? 
and so forth...
Then I've got independent variables related to socioeconomic factors and 
energy preferences.

I know I can treat the dv as continuous and use tobit or two part model 
(i.e. first probit and then truncated), or just OLS. Also, data is censored 
at ZERO
Also, I could use ordered probit or logit but I loose some of the 
information I have.

Due to the small amount of obs, what model do you recommend me to use? And, 
how should I decide between the different alternatives?

Thanks in advance


Augusto 

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