[MontaniSemperLiberi]

As a point....

There are Cumulative Distribution Functions (CDF’s) and Probability Distribution Functions (PDF’s). There are no Cumulative Probability Distributions. What you showed was a graph of the CDF (sort of).

[Political Junkie Too]

All the classes that I've taken refer to S-Curves as cumulative probability distributions because they are formed by sorting the outcomes and adding up the individual outcome probabilities. The plots show increasing probability outcomes until you reach 100% probability and the associated outcome.

The cumulative probability distribution shows the probability of the outcome being that result or less.

Perhaps you're thinking of something else?

-PJ