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: nlogit / asclogit replicate choice-alternatives per case

From   Nils Wlömert <>
Subject   st: nlogit / asclogit replicate choice-alternatives per case
Date   Thu, 2 Dec 2010 22:38:05 +0100

Dear listers,

my choice desingn includes multiple consecutive choice decisions per respondent (8 choices á 4 alternatives) and in some cases an alternative occurs twice per case (in different choice decisions).

This seems to cause problems estimating asclogit and nlogit and the following error messages occur:

nlogit: "note: 2324 cases (74368 obs) dropped due to no positive outcome or multiple positive outcomes per case" asclogit: "variable alternative has replicate levels for one or more cases; this is not allowed"

(How) Is it possible to estimate asclogit and nlogit with multiple consecutive choices and replicate alternatives (in different choice decisions) per case? I have tried estimating both models with only one choice decision per case (4 alternatives each) which works fine.

Also, when estimating asclogit with effects-type coding the model does not converge due to collinearity (3 out of 26 parameters are dropped). asclogit: "note: model has collinear variables; convergence may not be achieved" What would be the best way to deal with collinarity in this case? The model does not converge when the parameters are kept.

Many thanks!


*   For searches and help try:

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