Re: st: Ordered Logit - Should I use it or not

[Christoph Engel <engel@coll.mpg.de>]

Augusto,

There would be nothing wrong with using ordered logit. If you do, you 
loose information though. You know how far each step is different from 
the next, and you know that the final step is different by two steps of 
2.5 from the previous. Given this final feature of your data, OLS may 
eventually be better (and many would accept it with a variable of 6 
expressions). If you want to be more scrupulous, you might also run an 
interval regression

intreg

This regression exploits the information about the fact that the 
distance from 0 to 2.5 is the same as the distance from 2.5 to 5, and so 
forth. As for the syntax, you must generate a lower level, e.g.

gen low = dv - 1.25

and an upper level

gen high = dv + 1.25

and would then run

intreg low high ivs

Hope this helps

Christoph Engel

Am 7/14/2012 4:41 PM, schrieb Augusto Pallavicini:
> Hi all,
> I wanted to know whether I should use ordered logit. I am working on a 
> contingent valuation dissertation.
> My dependent variable is willingness to pay and contains the values 0; 
> 2.5; 5; 7.5; 10; 15.
> I transformed these values into 6 categories 1 2 3 4 5 6
> The original question from which I obtained the data was Would you 
> willing to pay 2.5 pounds for...? If yes, would you willing to pay 
> 5...? and so on
> If I cannot use ordered logit, what do you recommend me to use?
> Thanks a lot
> Augusto
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Prof. Dr. Christoph Engel
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