Final answer:
The question's context is not clear, making it challenging to define long and short PPST as associated with Whiting without more information.
Step-by-step explanation:
I’m sorry, but without additional context to specify what “PPST” refers to, it is challenging to give an accurate answer to how Whiting defined long and short PPST. The abbreviation “PPST” could stand for a variety of terms in different academic or professional fields, and I am not familiar with a definition of long and short PPST by someone with the last name Whiting. If you can provide more context or specify the area of study this question pertains to, I'd be happy to help!