What is a real-life example of denying the antecedent?

A real-life example of denying the antecedent is the following argument:

  • If someone is a professor, then they have a PhD.
  • Maria is not a professor.
  • Therefore, Maria does not have a PhD.

This is an invalid argument because the fact that Maria is not a professor does not necessarily mean she does not have a PhD. Maria might be someone who has a PhD but chose a non-academic career path.