# \#multinomial-response

**URL:** https://discourse.mc-stan.org/tag/multinomial-response/111.md

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## [Modelling the winner of board games](https://discourse.mc-stan.org/t/modelling-the-winner-of-board-games/18776)

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**Author:** [@ldeschamps](https://discourse.mc-stan.org/u/ldeschamps)\
**Replies:** 9\
**Last updated:** [July 15, 2025, 7:34pm UTC](https://discourse.mc-stan.org/t/modelling-the-winner-of-board-games/18776 "2025-07-15T19:34:01Z")

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Hi! I have a hard time wrapping my head around a model we’d like to fit. The objective is to estimate the probability of winning of each member of a board-game group. The deterministic part of the model would be relat…

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## [Multinomial logistic regression with categorical family (brms)](https://discourse.mc-stan.org/t/multinomial-logistic-regression-with-categorical-family-brms/39398)

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**Author:** [@romane\_ar](https://discourse.mc-stan.org/u/romane_ar)\
**Replies:** 5\
**Last updated:** [May 2, 2025, 7:50am UTC](https://discourse.mc-stan.org/t/multinomial-logistic-regression-with-categorical-family-brms/39398 "2025-05-02T07:50:51Z")

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Hi everyone, I’m new here and in general new with bayesian statistics and need some help. I work on R, and I’m quite confortable with frequentist stats in general but bayesian is quite new for me. -I am doing analyses …

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## [Reference levels and model interpretation](https://discourse.mc-stan.org/t/reference-levels-and-model-interpretation/38830)

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**Author:** [@FeliOtte](https://discourse.mc-stan.org/u/FeliOtte)\
**Replies:** 2\
**Last updated:** [February 26, 2025, 3:50pm UTC](https://discourse.mc-stan.org/t/reference-levels-and-model-interpretation/38830 "2025-02-26T15:50:27Z")

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Hi all! I’m currently running a categorical brms model that looks as follows: mdl ← brm (A ~ B + (1 | participant), dataset, family = categorical(), cores = 4, backend = “cmdstanr”) with A being the categorical outcom…

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## [Priors for multinomial logistic regression in brms](https://discourse.mc-stan.org/t/priors-for-multinomial-logistic-regression-in-brms/38424)

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**Author:** [@FeliOtte](https://discourse.mc-stan.org/u/FeliOtte)\
**Replies:** 5\
**Last updated:** [February 13, 2025, 10:31am UTC](https://discourse.mc-stan.org/t/priors-for-multinomial-logistic-regression-in-brms/38424 "2025-02-13T10:31:41Z")

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Hi everyone, I’m trying to run a multinomial logistic regression model in brms and am struggling to set priors. I only have 3000 data points (actually a lot of data in my field, but not for statistical modelling), so I’…

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## [Multinomial ‘one vs rest’ regression](https://discourse.mc-stan.org/t/multinomial-one-vs-rest-regression/37704)

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**Author:** [@tj\_1995](https://discourse.mc-stan.org/u/tj_1995)\
**Replies:** 4\
**Last updated:** [December 24, 2024, 8:56pm UTC](https://discourse.mc-stan.org/t/multinomial-one-vs-rest-regression/37704 "2024-12-24T20:56:42Z")

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Dear all, I’m very new to brms and stats in general but I want to know it it’s possible to do ‘one vs rest’ polytomous regression using BRMS, as so far I’ve only been able to do multinomial regression using the syntax: b…

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## [Conditional\_effects() plots from brms model has a response category with consistent 0 probability (flat plot)](https://discourse.mc-stan.org/t/conditional-effects-plots-from-brms-model-has-a-response-category-with-consistent-0-probability-flat-plot/35774)

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**Author:** [@LeoJha](https://discourse.mc-stan.org/u/LeoJha)\
**Replies:** 1\
**Last updated:** [July 23, 2024, 9:22pm UTC](https://discourse.mc-stan.org/t/conditional-effects-plots-from-brms-model-has-a-response-category-with-consistent-0-probability-flat-plot/35774 "2024-07-23T21:22:23Z")

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Hello, I have a multinomial logistic regression model (code below) using brm() with the response variable is six different species. Model converges nicely and the summary output (see below) shows that one of the six spe…

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## [Post-hoc test for multinomial logistic regression brm model (categorical responce)](https://discourse.mc-stan.org/t/post-hoc-test-for-multinomial-logistic-regression-brm-model-categorical-responce/35707)

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**Author:** [@LeoJha](https://discourse.mc-stan.org/u/LeoJha)\
**Replies:** 4\
**Last updated:** [July 7, 2024, 1:40am UTC](https://discourse.mc-stan.org/t/post-hoc-test-for-multinomial-logistic-regression-brm-model-categorical-responce/35707 "2024-07-07T01:40:46Z")

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I apologise as I am very new to this package and I really appreciate any help I can get. I have a brms model with a categorical response variable (Species) with the following formula, running a multinomial logistics reg…

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## [Prior and Model Selection for Multinomial Logistic Regression](https://discourse.mc-stan.org/t/prior-and-model-selection-for-multinomial-logistic-regression/34710)

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**Author:** [@Nana](https://discourse.mc-stan.org/u/Nana)\
**Replies:** 4\
**Last updated:** [April 8, 2024, 4:06pm UTC](https://discourse.mc-stan.org/t/prior-and-model-selection-for-multinomial-logistic-regression/34710 "2024-04-08T16:06:31Z")

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Dear Stan Community, For the analysis of a long-term study, I would like to perform a multinomial logistic regression to predict the affiliation to different progression groups (e.g. previously healthy, now ill or previ…

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## [Parallelization in cmdstanr: using reduce\_sum() on a multinomial likelihood](https://discourse.mc-stan.org/t/parallelization-in-cmdstanr-using-reduce-sum-on-a-multinomial-likelihood/24607)

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**Author:** [@joaneelleouet](https://discourse.mc-stan.org/u/joaneelleouet)\
**Replies:** 14\
**Last updated:** [January 9, 2024, 10:02am UTC](https://discourse.mc-stan.org/t/parallelization-in-cmdstanr-using-reduce-sum-on-a-multinomial-likelihood/24607 "2024-01-09T10:02:59Z")

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Hello, I am currently working on a multinomial regression model with many covariates and a large dataset. I am interested in reducing runtime by using within-chain parallelization. I initially thought the multinomial wa…

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## [Polling model with latent correlated random walk](https://discourse.mc-stan.org/t/polling-model-with-latent-correlated-random-walk/33550)

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**Author:** [@RobertoCerina](https://discourse.mc-stan.org/u/RobertoCerina)\
**Replies:** 4\
**Last updated:** [December 29, 2023, 11:16am UTC](https://discourse.mc-stan.org/t/polling-model-with-latent-correlated-random-walk/33550 "2023-12-29T11:16:26Z")

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Dear all, I’m looking for some modeling advice for the following setup to model daily polls at a national level. I’m first going to describe the setup, then present the model and define the problem, and then ask a coupl…

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## [Issue with model: Gradient evaluated at the initial value is not finite](https://discourse.mc-stan.org/t/issue-with-model-gradient-evaluated-at-the-initial-value-is-not-finite/32742)

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**Author:** [@matheusbarrosb](https://discourse.mc-stan.org/u/matheusbarrosb)\
**Replies:** 9\
**Last updated:** [September 14, 2023, 7:14am UTC](https://discourse.mc-stan.org/t/issue-with-model-gradient-evaluated-at-the-initial-value-is-not-finite/32742 "2023-09-14T07:14:49Z")

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Please share your Stan program and accompanying data if possible. Hello all, I have been trying to implement a hierarchical Dirichlet-Multinomial model for analyzing spatial variation in fish diet composition. My para…

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## [Use categorical /multinomial family with binary-ish data based on separate column in brms](https://discourse.mc-stan.org/t/use-categorical-multinomial-family-with-binary-ish-data-based-on-separate-column-in-brms/32383)

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**Author:** [@andrewheiss](https://discourse.mc-stan.org/u/andrewheiss)\
**Replies:** 8\
**Last updated:** [August 8, 2023, 5:55pm UTC](https://discourse.mc-stan.org/t/use-categorical-multinomial-family-with-binary-ish-data-based-on-separate-column-in-brms/32383 "2023-08-08T17:55:56Z")

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{brms} supports multinomial models with the categorical() family, and it works well as long as the response variable has 3+ categories in it. The {mlogit} R package allows you to fit multinomial logitistic models in a f…

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## [Psychometric lapsing model for more than two possible categorical outcomes](https://discourse.mc-stan.org/t/psychometric-lapsing-model-for-more-than-two-possible-categorical-outcomes/30600)

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**Author:** [@tiflo](https://discourse.mc-stan.org/u/tiflo)\
**Replies:** 3\
**Last updated:** [March 7, 2023, 2:20pm UTC](https://discourse.mc-stan.org/t/psychometric-lapsing-model-for-more-than-two-possible-categorical-outcomes/30600 "2023-03-07T14:20:50Z")

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Hi, I’m wondering whether there is a way to use brms to fit a psychometric lapsing model for a multi-response (categorical rather than bernoulli-distributed) outcome? To make this more concrete, I’m trying to analyze wh…

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## [Multinomial model with spline and interaction - getting output from continous and categorical variable together](https://discourse.mc-stan.org/t/multinomial-model-with-spline-and-interaction-getting-output-from-continous-and-categorical-variable-together/28155)

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**Author:** [@MiaKronborg](https://discourse.mc-stan.org/u/MiaKronborg)\
**Replies:** 1\
**Last updated:** [July 27, 2022, 12:31pm UTC](https://discourse.mc-stan.org/t/multinomial-model-with-spline-and-interaction-getting-output-from-continous-and-categorical-variable-together/28155 "2022-07-27T12:31:57Z")

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Hi, I am having issues with extracting specific output from the brms function. I want to model how the probability of being in one of three categories changes with both age and sex of an individual. But the output from …

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## [How to find theoretical Beta parameters boundaries in multinomial model?](https://discourse.mc-stan.org/t/how-to-find-theoretical-beta-parameters-boundaries-in-multinomial-model/27146)

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**Author:** [@Nicodeguines](https://discourse.mc-stan.org/u/Nicodeguines)\
**Replies:** 4\
**Last updated:** [April 26, 2022, 9:29am UTC](https://discourse.mc-stan.org/t/how-to-find-theoretical-beta-parameters-boundaries-in-multinomial-model/27146 "2022-04-26T09:29:30Z")

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Hello everyone, I hope my question has not been asked and answered in any previous posts (I haven’t found it, so hopefully this won’t be redundant). My question is about the estimation/interpretation of beta parameters…

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## [Testing an "omnibus" effect of a variable across the output categories](https://discourse.mc-stan.org/t/testing-an-omnibus-effect-of-a-variable-across-the-output-categories/26936)

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**Author:** [@MikeKSU](https://discourse.mc-stan.org/u/MikeKSU)\
**Replies:** 5\
**Last updated:** [April 1, 2022, 8:22pm UTC](https://discourse.mc-stan.org/t/testing-an-omnibus-effect-of-a-variable-across-the-output-categories/26936 "2022-04-01T20:22:11Z")

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I’m new to this forum, so I hope I don’t come across as an idiot. :). This seems like such a basic question, but I’m just not confident since I’m new to multinomial models. It’s a simple situation - one two-level predi…

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## [Specifying a Multinomial Logistic Regression with Unpooled Estimates](https://discourse.mc-stan.org/t/specifying-a-multinomial-logistic-regression-with-unpooled-estimates/25434)

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**Author:** [@Tikavdm](https://discourse.mc-stan.org/u/Tikavdm)\
**Replies:** 3\
**Last updated:** [November 29, 2021, 3:08pm UTC](https://discourse.mc-stan.org/t/specifying-a-multinomial-logistic-regression-with-unpooled-estimates/25434 "2021-11-29T15:08:14Z")

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Apologies if there are simple mistakes in this code, this is probably my second Stan model ever and I still have a lot to learn i.t.o data types/structures and other Stan model specifications. I am trying to fit a Multi…

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## [Answers conditions inside model block](https://discourse.mc-stan.org/t/answers-conditions-inside-model-block/24416)

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**Author:** [@NicholasWE](https://discourse.mc-stan.org/u/NicholasWE)\
**Replies:** 4\
**Last updated:** [September 27, 2021, 6:57pm UTC](https://discourse.mc-stan.org/t/answers-conditions-inside-model-block/24416 "2021-09-27T18:57:54Z")

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Hello, everybody! I have an array of categorical answers y (in Y), where each column is associated with a time t (in T) and each row with an individual i (in N). For each time t , I have the design matrix X and an auxi…

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## [Padding values in response arrays with different sizes](https://discourse.mc-stan.org/t/padding-values-in-response-arrays-with-different-sizes/23731)

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**Author:** [@NicholasWE](https://discourse.mc-stan.org/u/NicholasWE)\
**Replies:** 5\
**Last updated:** [August 2, 2021, 6:40pm UTC](https://discourse.mc-stan.org/t/padding-values-in-response-arrays-with-different-sizes/23731 "2021-08-02T18:40:24Z")

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Hello, everybody. I have multinomial observations for N individuals over T times and have to iterate through it (T). For a specific reason, I don’t have all N observations for every t in T. As I’m modeling a categoric…

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## [Categorical\_logit\_glm\_lpmf not found](https://discourse.mc-stan.org/t/categorical-logit-glm-lpmf-not-found/23468)

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**Author:** [@NicholasWE](https://discourse.mc-stan.org/u/NicholasWE)\
**Replies:** 1\
**Last updated:** [July 15, 2021, 12:36am UTC](https://discourse.mc-stan.org/t/categorical-logit-glm-lpmf-not-found/23468 "2021-07-15T00:36:34Z")

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Hello, everybodyy! First of all, forgive my language mistakes, but I’ll try to explain my doubt. I’m trying to estimate parameters of a categorical logistic regression and found the Stan’s Softmax Regression. I know h…

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## [Multinomial Logit: probability of choice of a soccer action](https://discourse.mc-stan.org/t/multinomial-logit-probability-of-choice-of-a-soccer-action/20334)

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**Author:** [@Sebastian\_Mena](https://discourse.mc-stan.org/u/Sebastian_Mena)\
**Replies:** 24\
**Last updated:** [March 9, 2021, 6:12pm UTC](https://discourse.mc-stan.org/t/multinomial-logit-probability-of-choice-of-a-soccer-action/20334 "2021-03-09T18:12:41Z")

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Hello, I’d like to do a stan model (in python) to get the probability of an action choice of a soccer game. Specificly, i have 3 kinds of actions: Shots, Pass and Dribblings. Each soccer player “can choose” one of this…

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## [Gaussian Processes for a categorical (multinomial) model](https://discourse.mc-stan.org/t/gaussian-processes-for-a-categorical-multinomial-model/19802)

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**Author:** [@jeremy.koster](https://discourse.mc-stan.org/u/jeremy.koster)\
**Replies:** 2\
**Last updated:** [December 14, 2020, 4:29pm UTC](https://discourse.mc-stan.org/t/gaussian-processes-for-a-categorical-multinomial-model/19802 "2020-12-14T16:29:01Z")

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@paul.buerkner In principle, can brms handle Gaussian Processes for a categorical (~multinomial) model? This would presumably apply the correlation matrix to each of the sub-functions within the categorical model. Is th…

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## [Acessing element out of range - Multinomial Regression](https://discourse.mc-stan.org/t/acessing-element-out-of-range-multinomial-regression/19641)

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**Author:** [@bhopalstiffs](https://discourse.mc-stan.org/u/bhopalstiffs)\
**Replies:** 2\
**Last updated:** [December 5, 2020, 12:49am UTC](https://discourse.mc-stan.org/t/acessing-element-out-of-range-multinomial-regression/19641 "2020-12-05T00:49:11Z")

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Hello, First time poster. I am trying to fit a multinomial regression model in RStan. I have species richness counts/outcome value (1-8) and vegetation types (1-14) from 645 sites. I am trying to estimate the probabil…

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## [Can you use a horseshoe prior with a categorical model?](https://discourse.mc-stan.org/t/can-you-use-a-horseshoe-prior-with-a-categorical-model/16151)

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**Author:** [@JCrans101](https://discourse.mc-stan.org/u/JCrans101)\
**Replies:** 2\
**Last updated:** [June 22, 2020, 7:21pm UTC](https://discourse.mc-stan.org/t/can-you-use-a-horseshoe-prior-with-a-categorical-model/16151 "2020-06-22T19:21:46Z")

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Hi, I’m quite new to brms so apologies if this is a naive question. I’m trying to fit a multinomial model each datapoint belongs to one of three categories I’m trying to predict which with c. 10 predictors. I suspect m…

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## [Setting priors for multinomial regression in brms](https://discourse.mc-stan.org/t/setting-priors-for-multinomial-regression-in-brms/15911)

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**Author:** [@filippogambarota](https://discourse.mc-stan.org/u/filippogambarota)\
**Replies:** 5\
**Last updated:** [June 14, 2020, 10:21am UTC](https://discourse.mc-stan.org/t/setting-priors-for-multinomial-regression-in-brms/15911 "2020-06-14T10:21:41Z")

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Hi, I’m new to bayesian modelling and brms so maybe my question is trivial. However, I’m fitting a multinomial regression using brms. The response variable response is modeled as a function of a binary factor GROUP and t…

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## [Hierarchical Multinomial Model Optimization/Specification](https://discourse.mc-stan.org/t/hierarchical-multinomial-model-optimization-specification/14644)

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**Author:** [@JLC](https://discourse.mc-stan.org/u/JLC)\
**Replies:** 15\
**Last updated:** [May 7, 2020, 12:14pm UTC](https://discourse.mc-stan.org/t/hierarchical-multinomial-model-optimization-specification/14644 "2020-05-07T12:14:19Z")

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I am currently trying to analyze some multinomial data (8 possible categorical responses in each row) with a hierarchical model. The data are generated from 16 groups of people (8 groups in “control”, 8 groups in "inter…

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## [Hierarchical Multinomial Model taking days to run](https://discourse.mc-stan.org/t/hierarchical-multinomial-model-taking-days-to-run/13933)

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**Author:** [@JLC](https://discourse.mc-stan.org/u/JLC)\
**Replies:** 14\
**Last updated:** [April 9, 2020, 1:39pm UTC](https://discourse.mc-stan.org/t/hierarchical-multinomial-model-taking-days-to-run/13933 "2020-04-09T13:39:09Z")

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Please also provide the following information in addition to your question: Operating System: Ubuntu 19.10 brms Version: 2.12.0 I am relatively new to Bayesian inference and brms has made the transition very a…