boundaries should be exclusive in positive-constrained distributions like lognormal
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bug
- Dominant language
- C++
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Description
Description
Lines 26-27 of stan/math/prim/prob/lognormal_lpdf.hpp are:
check_not_nan(function, "Random variable", y);
check_nonnegative(function, "Random variable", y);
They should be replaced with:
check_positive_finite(function, "Random variable", y);
because 0 is not in the support of a lognormal.
For comparison, the test is implemented properly in gamma_lpdf.hpp.
There may be other
Current Version:
v3.2.0
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Research direction
Start with stan/math/prim/prob/lognormal_lpdf.hpp lines 26-27 and compare the validation used in gamma_lpdf.hpp. Update the lognormal random-variable check so zero is rejected, then review related positive-constrained distributions for the same boundary issue; done when the lognormal support check is exclusive.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 1/5
- Estimated time
- 1-3 hours
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 55/100