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Search found 7 matches

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by bartoszbartk
15 Oct 2024, 08:18
Forum: Errors during model validation and/or estimation.
Topic: Log-likelihood calculation fails at values close to the starting values
Replies: 3
Views: 30844

Re: Log-likelihood calculation fails at values close to the starting values

Thanks! (and sorry for the late response, I was away the last two weeks) I just tried changing the starting value for m_log_b_cost to -5 (which is pretty close to its actual value according to the models that have worked so far) - same result: "CALCULATION ISSUE - Log-likelihood calculation fails at ...
by bartoszbartk
26 Sep 2024, 07:54
Forum: Errors during model validation and/or estimation.
Topic: Log-likelihood calculation fails at values close to the starting values
Replies: 3
Views: 30844

Log-likelihood calculation fails at values close to the starting values

Hi!

I have a pretty complex model (lots of interactions). Originally, I estimated it in WTP space, but now I'd like to have it also in preference space (easier to interpret, at least for me). The problem is that the preference space version doesn't work (the error always is "CALCULATION ISSUE - Log ...
by bartoszbartk
02 May 2022, 14:30
Forum: Post-estimation analysis/use of results
Topic: Conditionals from WTP space mixed logit perfectly correlated across individuals
Replies: 8
Views: 12827

Re: Conditionals from WTP space mixed logit perfectly correlated across individuals

Thanks for spotting this! I reran the models after correcting this mistake, all seems to be fine!
Best,
Bartosz
by bartoszbartk
27 Apr 2022, 07:14
Forum: Post-estimation analysis/use of results
Topic: Conditionals from WTP space mixed logit perfectly correlated across individuals
Replies: 8
Views: 12827

Re: Conditionals from WTP space mixed logit perfectly correlated across individuals

Hi Stephane,

sorry, here they come:

Correlation matrix:
drought.m flood.m climate.m water.m
drought.m 1 1 1 1
flood.m 1 1 1 1
climate.m 1 1 1 1
water.m 1 1 1 1

Variance-covariance matrix:
drought.m flood.m climate.m water.m
drought.m 0.1959491 0.1780087 0.3280592 1.0071095
flood.m 0.1780087 0 ...
by bartoszbartk
26 Apr 2022, 14:20
Forum: Post-estimation analysis/use of results
Topic: Conditionals from WTP space mixed logit perfectly correlated across individuals
Replies: 8
Views: 12827

Re: Conditionals from WTP space mixed logit perfectly correlated across individuals

Hi! I am not sure that I sent my response last Thursday. Just in case I haven't, here's the correlation matrix of the mixed logit model:
Classical correlation matrix:
asc_2 asc_3 mu_b_drought mu_b_flood
asc_2 1.000000 0.126005 0.005341 -7.292e-05
asc_3 0.126005 1.000000 -0.164257 -0.253828
mu_b ...
by bartoszbartk
21 Apr 2022, 10:58
Forum: Post-estimation analysis/use of results
Topic: Conditionals from WTP space mixed logit perfectly correlated across individuals
Replies: 8
Views: 12827

Re: Conditionals from WTP space mixed logit perfectly correlated across individuals

Hi Stephane,

thanks for the quick response. Here are the summaries of the conditionals:
> summary(conditionals[["b_drought"]])
ID post.mean post.sd
Min. : 1.0 Min. :-1.7831 Min. :0.04655
1st Qu.: 375.0 1st Qu.:-0.9891 1st Qu.:0.24811
Median : 750.0 Median :-0.6229 Median :0.34211
Mean ...
by bartoszbartk
20 Apr 2022, 17:17
Forum: Post-estimation analysis/use of results
Topic: Conditionals from WTP space mixed logit perfectly correlated across individuals
Replies: 8
Views: 12827

Conditionals from WTP space mixed logit perfectly correlated across individuals

Hi,

I estimated a mixed logit in WTP space for four normally distributed ES attributes and a lognormally distributed price attribute. Here's the output of the model:

Estimation method : bfgs
Model diagnosis : successful convergence
Number of individuals : 1481
Number of rows in database : 13329 ...

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