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by wj5tu
15 Apr 2021, 04:55
Forum: Model specification
Topic: Apollo_example_16
Replies: 1
Views: 7106

Apollo_example_16

Hi Prof. Hess,

In example 16, for the business shift for the random coefficient "v_tt", you use multiplication instead of addition, would you share your consideration for such a specification?

randcoeff[["v_tt"]] = ( exp( mu_log_v_tt
+ sigma_log_v_tt_inter * draws_tt_inter
+ sigma_log_v_tt ...
by wj5tu
21 Oct 2020, 21:08
Forum: Model specification
Topic: latent class with best-worst data
Replies: 3
Views: 21173

Re: latent class with best-worst data

Hi Prof. Hess,

Thanks! it works! So there is no need to transform the dataset.

By the way, the result is the same as when I transform the dataset. The only difference is BIC value, as after transforming the dataset, the number of observations doubles.

Best,
Wenjian
by wj5tu
19 Oct 2020, 22:27
Forum: Model specification
Topic: latent class with best-worst data
Replies: 3
Views: 21173

latent class with best-worst data

Hi Prof. Hess,

Please ignore my last post regrading "latent class with best-worst data", as I believe the specification is wrong (also attached here). So previously what I have done is, first look at within class probability of best choices, average across all classes, then the within class ...
by wj5tu
19 Oct 2020, 04:56
Forum: Model specification
Topic: Observed and unobserved heterogeneity
Replies: 3
Views: 11002

Re: Observed and unobserved heterogeneity

Hi Prof. Hess,

Thanks for your help! I found the estimated income elasticity to be highly insignificant. So I tried another specification by interacting cost coefficient with a high-income dummy.

randcoeff[["rand_cost"]] = - exp(b_cost + sigma_cost * norm_draws) * (delta * income_high + (1 ...
by wj5tu
21 May 2020, 03:18
Forum: Post-estimation analysis/use of results
Topic: conditionals for random parameters when an individual has lots of observations
Replies: 5
Views: 15399

Re: conditionals for random parameters when an individual has lots of observations

Hi Prof. Hess,

Thanks for your suggestions! I believe it is a good idea to first examine observed heterogeneity.

Besides, I can think of another route to address the numerical issue. Instead of using state as an "individual", maybe use a smaller geographic unit (e.g., county, blocks, etc.). In ...
by wj5tu
15 May 2020, 21:23
Forum: Post-estimation analysis/use of results
Topic: conditionals for random parameters when an individual has lots of observations
Replies: 5
Views: 15399

Re: conditionals for random parameters when an individual has lots of observations

Hi Prof. Hess,

Thank you very much for your time and insights!

My data is not a typical choice dataset. Below is a brief context of this case:

Data: national sample, some states have more than 2000 samples, while those less populated states may have only about 300 samples.
Dependent variable ...
by wj5tu
15 May 2020, 01:36
Forum: Post-estimation analysis/use of results
Topic: conditionals for random parameters when an individual has lots of observations
Replies: 5
Views: 15399

conditionals for random parameters when an individual has lots of observations

Dear Prof. Hess,

In my dataset, each individual has many observations (ranges from 50 to 3000). When estimating a random parameter model, I had to set "workInLogs = TRUE" to avoid numerical issues, and it works.

Then, I want to look at posterior conditionals for those random parameters using ...

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