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Calculating logsum from the estimated model

Ask questions about post-estimation functions (e.g. prediction, conditionals, etc) or other processing of results.
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Calculating logsum from the estimated model

Post by punyabeet » 22 Oct 2021, 13:25

Hi Prof Hess/ Prof Palma

While estimating a nested logit with 4 nests, I get 3 log sum parameters. Two values are below 1 while one is above 2.

So is the output normalized and it should come between 0 and 1 or is it 1/(log sum Parameter).

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Re: Calculating logsum from the estimated model

Post by stephanehess » 25 Oct 2021, 08:45


if you have 4 nests, you should have 4 structural parameters too, unless you have fixed the structural parameter in one of the nests (e.g. if it is a single alternative nest).

I assume you've set the lambda at the root equal to 1, in which case the other lambdas should all be between 0 and 1.

Stephane Hess

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