Define the World
To calculate precise probabilities, we first need to define the exact events. What are you trying to predict, and what new information did you observe?
Evaluating Probability
A:
Given B:
Prior: P()
Frequentist view: out of 100 times, naturally occurs before considering any new evidence.
Evidence Strength
P( | )
Frequentist view: If occurred, out of 100 times would we observe .
P( | not )
Frequentist view: If did NOT occur, out of 100 times would we observe anyway.
Updated Probability
Posterior: P( | )
Frequentist view: Out of 100 times we observe , is actually true times.