Help with pm.Potential

Questions
12

I think that worked! Here’s what I have now:

import numpy as np
import pymc3 as pm
import arviz as az
import theano.tensor as tt

print(f"Running on PyMC3 v{pm.__version__}")

np.random.seed(451)
x = np.random.exponential(3,size=500)

minx=1
maxx=20

obs = x[np.where(~((x<minx) | (x>maxx)))] # remove values outside range

def censor_correct(λ):
    result = -tt.log(tt.exp(-minx/λ)- tt.exp(-maxx/λ))*len(obs)
    return result
    
with pm.Model() as expModel:
    λ = pm.Exponential("λ", lam=1/5)  # prior exponential with mean of 5
    clip_exp = pm.Potential("clip_exp", censor_correct(λ))
    x = pm.Exponential('x', lam=1/λ, observed=obs) # obs exponential with mean of $\lambda$.
    
    trace= pm.sample(2000, tune=1000, return_inferencedata=True)

az.summary(trace)

	mean	sd	    hdi_3%	hdi_97%	
λ	2.895	0.159	2.603	3.199

Thank you!

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