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Search found 1261 matches

by stephanehess
21 Mar 2025, 15:27
Forum: Estimation results
Topic: HCM model rho square not applicable problem
Replies: 1
Views: 87

Re: HCM model rho square not applicable problem

Hi

rho2 is a metric for discrete choice. So if you use a continuous measurement model for your indicators, then rho2 cannot be calculated

Stephane
by stephanehess
20 Mar 2025, 15:30
Forum: Model specification
Topic: Estimation failed on Joint estimation on RP and SP data
Replies: 3
Views: 516

Re: Estimation failed on Joint estimation on RP and SP data

Hi

your SP model doesn't seem to work either if you look at the standard errors, and esepcially b_robusta and b_arabica

Stephane
by stephanehess
20 Mar 2025, 15:28
Forum: Errors during model validation and/or estimation.
Topic: WARNING: Estimation failed. No covariance matrix to compute. MNL
Replies: 3
Views: 512

Re: WARNING: Estimation failed. No covariance matrix to compute. MNL

Dennis

difficult to know a priori what is causing the identification issue then. I suggest you look at adding one attribute at a time to see where it goes wrong

Stephane
by stephanehess
20 Mar 2025, 08:18
Forum: Errors during model validation and/or estimation.
Topic: Error in LCCM using RP SP data
Replies: 3
Views: 2176

Re: Error in LCCM using RP SP data

Hi

just put 0 instead of NA.

Stephane
by stephanehess
20 Mar 2025, 08:16
Forum: Model estimation
Topic: The estimation method was changed to BFGS automatically.
Replies: 2
Views: 550

Re: The estimation method was changed to BFGS automatically.

Hi

this would suggest that those computers are using an old version of R and/or an old version of Apollo

Stephane
by stephanehess
20 Mar 2025, 08:15
Forum: Model specification
Topic: Estimation failed on Joint estimation on RP and SP data
Replies: 3
Views: 516

Re: Estimation failed on Joint estimation on RP and SP data

Hi

do the separate RP and SP models work?

Best wishes

Stephane
by stephanehess
20 Mar 2025, 08:13
Forum: Errors during model validation and/or estimation.
Topic: WARNING: Estimation failed. No covariance matrix to compute. MNL
Replies: 3
Views: 512

Re: WARNING: Estimation failed. No covariance matrix to compute. MNL

Hi

your model is overspecified. I don't see where you implemented effects coding, but I suggest you use dummy coding, which is much easier (and gives the same findings). Either way, for an attribute with three levels, you can only estimate two parameters, not three

Stephane
by stephanehess
20 Mar 2025, 08:11
Forum: Model specification
Topic: Defining the optout
Replies: 1
Views: 118

Re: Defining the optout

Hi

the two models are mathematically identical. The fact that the opt-out constant changes makes me think that the attribute you are talking about also relates to the opt-out. Is a specific level for that attribute also the base for the opt-out?

Stephane
by stephanehess
13 Mar 2025, 09:45
Forum: Errors during model validation and/or estimation.
Topic: Error in LCCM using RP SP data
Replies: 3
Views: 2176

Re: Error in LCCM using RP SP data

Hi

do you have some NA in your data? That would cause this problem

Stephane
by stephanehess
12 Mar 2025, 18:43
Forum: Model estimation
Topic: Latent Class model with EM algorithm
Replies: 1
Views: 1894

Re: Latent Class model with EM algorithm

Hi there

it looks like your EM estimation converged to a pretty bad solution. This is somewhat surprising, but EM does not in fact guarantee convergence to a better solution than classical estimation. Did you try some other starting values?

Stephane