A Peta Perspective on the Hot Stove So Far

Cold snowy days here in our nation’s capital, combined with the owners’ and players’ seeming determination to kill the golden goose, provides an opportunity for me to look at the hot stove (pre-lockout) through the lens of the Peta methodology. For those unfamiliar with the Peta methodology, I refer you to this deeper dive here on the Community Blog published last January. Based on Joe Peta’s groundbreaking 2013 book Trading Bases, the methodology derives each team’s upcoming season win-loss record based on the utilization of its previous season performance (runs scored/runs allowed), adjusted for cluster luck (my proxy is FG BaseRuns), and the team’s upcoming-season projected WAR.

Just before Opening Day, the product of this calculation is compared to the money line. Peta suggests that in a 162-game season, win totals produced by the model that deviate from the money line by more than four games (1.5 games in a 60- game season) represented “unrepeatable results” and therefore were worth a possible wager.

Application of the Peta methodology over the last two seasons has resulted in 12 wins in 14 identified deviations between the model and the money line:

There are two notes here regarding the 2021 season. From the jump, I had serious concerns about applying 2020’s 60-game stats to 2021’s 162-game season (click here for the entire projection). As a result, I cut way back on my season-long bets. I elected to focus on the model’s five most extreme outliers versus the money line, reasoning it would provide some “padding” in case the underlying projections were way off. Though in two cases it was close, it ended up well.

Second, I hope this explains my odd behavior at the Red Sox-Nats game on the last day of season. It was a great game, but for at least an hour my eyes were glued to the out-of-town scoreboard while listening to my son’s “play-by-play” of the MLB Gameday app. Let us just say that my emoting did not strictly track with the game on the field, especially when the Astros blew the lead, requiring the Athletics to do the same.

With that by way of backdrop, here is the first look at the 2022 season (as of 12/13/2021). To preempt the objections, let us remember first and foremost this is a snapshot in time. The chart will be updated throughout the hot stove (fingers crossed it is relit) all the way to the morning of Opening Day — when decisions must be made:

Right now there is a huge amount of unassigned WAR (i.e., unsigned free agents). As this FG chart indicates, the current WAR assigned to free agents (106.1) is twice the that of the best team in baseball, the Dodgers (49.4).

Are the Giants only going to win 81 games? Unlikely. Remember, win totals will change as teams add free agents. Further, since there are a finite number of wins (2,430), it is also a zero-sum game. For example, adding Freddie Freeman back to the Braves lineup results in a four-game increase in wins (from 92 to 96). It would also reduce the Mets’ total wins from 92 to 91.

Despite the limits of the data, a few observations can be made based on the story so far. First is the impact of BaseRuns. One of the first things that sent me back into the calculations was the number generated by the Mariners (78 wins). In this instance it comes down to one of the backbones of the methodology, adjusting for cluster luck (accounted for in this model by FG BaseRuns). Simply put, Seattle outplayed their statistics by a whopping 16 games. The next “luckiest” team was Boston at 6 wins above their stats. As a result, Seattle’s moves to date have improved the team, but throughout the hot stove the club will be digging out from their statistical over-performance.

On the flip side, this snapshot sees improvement coming for the Marlins and Diamondbacks. These improvements though are the other side of the BaseRuns coin, an addition of talent combined with 2021 records indicative of teams with results worse than their statistics suggested (Marlins -7 games and Diamondbacks -8 games).

Teams like the Mets and Rangers were relatively neutral in terms of BaseRuns (-4 and -3 respectively), making their addition of talent that much more significant in terms of improvement. But a stern chase is a long chase, and as the initial numbers indicate, there is still ground to be made up.

Finally, the Astros and Dodgers are still very good teams. There’s no Carlos Correa, but Houston is still a 91-win team thanks to -5 base runs in 2021. No Kershaw, no Scherzer, no problem for Los Angeles. From a BaseRuns perspective, the Dodgers were neutral (-1). So even before they add talent, they are still the class of the NL West at this point, though the Padres (-2) are closing the gap.