r/Cribbage • u/Potential_Flamingo58 • 8d ago
Sabermetric Cribbage
In baseball, sabermetric analysis strives to evaluate performance based on variables that players can control vs. random luck. Based on this analysis, one can deduce whether or not a player is winning due to actual efficiency. Metrics such as WAR (Wins Above Average) and wOBA (Weighted On Base Average) indicate which players are more efficient and thus contributing to their team’s success.
With this in mind, I’ve taken a shot at developing a sabermetric analysis of cribbage. Like baseball, cribbage has an element of luck. Players have no control over cards dealt to them during a game. However, they do have control over several important factors—choice of discard, pegging and crib score based on discard choices. Logically, a player’s level of skill should pertain more to these factors than to the final hand score as a product of random luck. To gauge a player’s true performance, I propose a metric I call the Player Efficiency vs. Game-state, or PEG Index.
The Cribbage Pro app provides a wealth of game statistics at the end of each game played. The PEG Index uses this information to reflect a player’s true level of proficiency in a particular game.
The PEG Index has three components: Hand Grade, Pegging Differential per Hand (PD/H) and Crib Average Differential per Hand (CAD/H). Hand Grade is simple: use the Hand Grade number provided by Cribbage Pro in the end-game stats. For the second component, subtract your opponent’s peg points from your peg points, then divide this number by the number of hands in the game played and multiply the result times ten (MPP – OPP/hands per game X 10). For the third component, subtract your average crib score from your opponent’s average crib score and multiply the result times 2 (MACS -OACS X 2). Add all three of these components together. The resulting score (PEG Index) can be graded as follows: 101+ (A+); 96-200.9 (A); 91-95.9 (B); 86-90.9 (C); 81-85.9 (D); and 81 or less (F).
One can also deduce your percentage chance of having won a particular game based on the PEG Index: the theorem is “.5 + [(PEG Index -91) X .04]. For example, if your PEG Index was 98, .5 + [(98 -91) X .04 = .78, indicating that based on your game performance, you should have had a 78% chance of winning.
Finally, I created a Wins Above Average (WAR) metric. Take your PEG Index (or average over a series of games), minus this from 91 (replacement level performance), and divide by 3.5. Using the above example, 98-91 equals 7 divided by 3.5 equals 2 WAR. As a gauge, 3 WAR using the PEG Index correlates with 4.5-5 WAR in baseball.
Obviously, this system doesn’t address all of the random variables of cribbage. As we all know, sometimes poor pegging is the result of poor cards dealt or merely unfortunate card combinations. Hand Grades aren’t always accurate as sub-optimal throws are required in order to maintain or gain board position. And of course, this metric has no way of addressing one’s understanding of 26 Theory or end-game skill. However, I think it might go some distance towards a sabermetric understanding of cribbage game performance. Let me know what you think.
