[HaveCourage]

Wrongful convictions: https://en.wikipedia.org/wiki/Prosecutor's_fallacy

Don't understand what your STD test really means: https://en.wikipedia.org/wiki/False_positive_paradox

Correlation/causation conflation.

[contravariant]

Both are basically people not understanding Bayes' law. Or, equivalently, the difference between (posterior) probability and likelihood.