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maksimhorowitz / nflscrapR

R Package for Scraping and Aggregating NFL Data
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WP seems off for field end-of-game situation #129

Open tunesmith opened 4 years ago

tunesmith commented 4 years ago

Denver/Chicago, week 2 2019. One second left, 35-yard line, Chicago is down by 1. nflscrapR WP model says Chicago has a 95.5% chance of winning. This is nowhere near the probability of making a field goal at that range. Next Gen Stats says it's a 53% chance (https://twitter.com/NextGenStats/status/1173382032128266240) to make the field goal, plus whatever chance of scoring a touchdown had they gone for it. Is there more information somewhere on how the WP model is calculated?

sventura commented 4 years ago

The WP model is documented in Section 3.2 here: https://arxiv.org/pdf/1802.00998.pdf

There is also a separate repository for the models: https://github.com/ryurko/nflscrapR-models

Just a guess, but it probably has something to do with the use of expected score differential in these edge cases.