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!

Nils.

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