Hi
your specification is correct but your results are worrying as the effect in the reference group is positive and as the income effect is not monotonic
Stephane
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Search found 1042 matches
- 09 May 2024, 06:30
- Forum: Data preparation, processing and pre-estimation analysis
- Topic: Handling 'Not Available' Data
- Replies: 3
- Views: 129
- 09 May 2024, 06:26
- Forum: Estimation results
- Topic: Positive price coefficient in RPL model estimation
- Replies: 10
- Views: 272
Re: Positive price coefficient in RPL model estimation
Okay, in that case, Normals might be okay. In terms of computing error measures, you can have a look at this paper (DOI: 10.1016/j.trb.2013.09.010) and think about how to set this up in Apollo, but it is not precoded
- 08 May 2024, 10:09
- Forum: Estimation results
- Topic: Positive price coefficient in RPL model estimation
- Replies: 10
- Views: 272
Re: Positive price coefficient in RPL model estimation
What are your attributes?
- 07 May 2024, 15:57
- Forum: Errors during model validation and/or estimation.
- Topic: Error in estimating Latent class model with RP-SP data
- Replies: 9
- Views: 192
Re: Error in estimating Latent class model with RP-SP data
yes, having all the starting values at zero also led to an issue with the initial check of the gradients. It's always good practice to use different starting values in different classes
- 07 May 2024, 10:24
- Forum: Errors during model validation and/or estimation.
- Topic: Error in estimating Latent class model with RP-SP data
- Replies: 9
- Views: 192
Re: Error in estimating Latent class model with RP-SP data
Hi two changes are needed in your code. As apollo_combineModels is called inside the latent class model, you need P[[paste0("Class_",s)]] = apollo_combineModels(P_temp, apollo_inputs, functionality,components=c(paste0("RP_class_",s),paste0("SP_class_",s)),asList=FALSE) ...
- 07 May 2024, 07:55
- Forum: Errors during model validation and/or estimation.
- Topic: Error in estimating Latent class model with RP-SP data
- Replies: 9
- Views: 192
Re: Error in estimating Latent class model with RP-SP data
Can you share your code and data with me outside the forum, and I'll try to debug it for you
- 07 May 2024, 07:52
- Forum: Estimation results
- Topic: Positive price coefficient in RPL model estimation
- Replies: 10
- Views: 272
Re: Positive price coefficient in RPL model estimation
you can do, if you really think a Normal makes sense (it normally does not)
- 06 May 2024, 13:09
- Forum: Model estimation
- Topic: Need Advice on Using CFA Model Results from other software with ICLV in Apollo
- Replies: 3
- Views: 110
Re: Need Advice on Using CFA Model Results from other software with ICLV in Apollo
Hi
yes, I understood you were doing the factor analysis in another package. But you would never use factor scores in an ICLV model. What would do is check what groupings the factor analysis gives you and implement the ICLV model accordingly
Stephane
yes, I understood you were doing the factor analysis in another package. But you would never use factor scores in an ICLV model. What would do is check what groupings the factor analysis gives you and implement the ICLV model accordingly
Stephane
- 06 May 2024, 08:26
- Forum: Model specification
- Topic: Two level Nested Logit(NL) model specification for many alternatives
- Replies: 1
- Views: 72
Re: Two level Nested Logit(NL) model specification for many alternatives
Hi
apologies for the slow reply, your message had got lost
Did you try with lambda=1 as a starting value. Essentially, you should first see if you can replicate MNL
Stephane
apologies for the slow reply, your message had got lost
Did you try with lambda=1 as a starting value. Essentially, you should first see if you can replicate MNL
Stephane
- 06 May 2024, 08:22
- Forum: Model specification
- Topic: Start values for wta parameter
- Replies: 3
- Views: 2609
Re: Start values for wta parameter
Anat
apologies for the very slow reply.
I would use a lognormal distribution indeed. It's not about whether you have an opt-out or not, really, but about whether it would make sense behaviourally for people to have a diferently signed coefficient
Stephane
apologies for the very slow reply.
I would use a lognormal distribution indeed. It's not about whether you have an opt-out or not, really, but about whether it would make sense behaviourally for people to have a diferently signed coefficient
Stephane