Statistical STA (SSTA)
Beginner
Timing checks that treat each delay as a range of likely values, not one number.
Novice
Timing analysis that treats each delay as a spread of possible values with probabilities, rather than a single worst-case number, and reports how likely each path is to fail.
Expert
Propagates delay distributions through the timing graph. Block-based SSTA writes every delay as a mean plus sensitivities to named sources of variation and approximates the max of two arrivals back into that form by matching moments. It yields sensitivities and criticality probabilities. POCV is the simpler statistical model most signoff flows run.