This is one of the key, desired metrics in Skateboarding Analytics. It’s the probability of successfully landing a trick given an attempt. I suspect that it should be thought of as only applying to attempts that occurred for that particular trick during the time period from which the data points that led to its estimation were collected. It remains to be seen whether they can be used for generalizing, or to estimate the probability in other time periods (Probability Generalization to Other Time Periods).