When executing my code I always see this warning message: WARNING:nimare.utils:Metadata field 'sample_sizes' not found. Set a constant value for this field as an argument, if possible. I ignore this since I explicitly set the sample size in nimare.meta.cbma.ale.ALE(null_method="approximate", kernel__sample_size=20). I wanted to clarify though whether this warning is innocuous or actually alerting me that I’m not properly setting this parameter, thereby affecting my results?
The warning can be ignored if you provided the kernel__sample_size parameter. The ALE Estimator would fail if you weren’t setting the sample size (or FWHM) correctly.