[Image 1] [image 2] in image 1 as my observed value are always greater than zero still i took likelihood as normal distribution in image 2 i changed my likelihood to exponential distribution and i also tried with gamma also now my question is as in image 1 , i have extra predictions which are …

Hi! Can you include the code that specifies the model, as well as the code you used to plot the posterior? Thanks, Keith

[image] Nij_PADARIYA: but still not able to cover whole graph What do you mean by this? [image] Nij_PADARIYA: so which is correct and which is not ? There are not “correct” or “incorrect” models. There are models you are happy with and one you are unhappy with. My suggestion would b…

[image] Bayesian Modeling of Disease Case Counts: Validity of Priors and Predictors Question: We are working on a project analyzing disease case counts across different regions in an Indian state. The administrative hierarchy follows a state → district → block structure.…

[image] Nij_PADARIYA: Can you check now this based on my data and model? I can, but I would need to see what the prior predictive looks like and even then, you would be the best person to evaluate whether the model is behaving in the way you wish.

I took a look at your model. It’s hard to tell what your graph is actually showing though. Could you paste your code for the second visualization? If it’s just showing a distribution plot of all Y_obs, I’m not sure how meaningful it is for figuring out what’s going on. I will say, though, your data …

it is not containing more zeros but the y_obs is mostly containing values near zero,

I mean the actual observed values. Didn’t you say they were counts? I’m assuming y has lots of zeros?

yes they are count of disease case but when i am normalizing it then it will become value near to zero

If you’re normalizing the data, then you definitely shouldn’t use an exponential distribution. The exponential distribution cannot model negative numbers. Consider leaving the counts as they are and doing something like this: GLM: Negative Binomial Regression — PyMC example gallery

Doubt regarding az.plot_ppc(trace)

Questions v5

Nij_PADARIYA February 5, 2025, 8:53am 5

Can you check now this based on my data and model?

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Doubt regarding az.plot_ppc(trace)

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