A Peta Perspective on the Hot Stove…So Far

Home » Blog » Baseball » A Peta Perspective on the Hot Stove…So Far
John Dreyfuss, Full Count, Washington, DC

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 to look at the hot stove (pre-lockout) through the lens of the Peta methodology.

The Peta Methodology

For those unfamiliar with the Peta methodology, I refer you to this deeper dive that FanGraphs (FG) 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 worth a possible wager.

Result to date

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:

Applying the Model to 2020 Outliers
Applying the Model to 2021 Outliers
TeamProjWm. HillDifSeasonBetResult
Blue Jays9687991OverW

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 ap. Let us just say that my emoting did not strictly track with the game on the field. Especially when the Astro’s blew the lead, requiring the Athletics to do the same.

First look at 2022

So, 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:

Bl. Jays91921Guardians80833Angels77825
Red Sox9278-14Twins73807Rangers607616
Yankees9290-2White Sox9384-9Mariners9078-12
American League
National League

The best team in baseball is…free agents

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 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.

Cluster luck an important factor

Despite the limits of the data, a few observations can be made based on the story so far:

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 team 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).

Money talks – 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 – No Correa, still a 91-win team thanks to -5 base runs in 2021. No Kershaw. No Scherzer. No Bellinger. No problem. From a baseruns perspective the Dodgers were neutral (-1). So even before the Dodgers add talent, at this point they are still the class of the NL West though the Padres (-2) are closing the gap.


  1. Do you have a spam issue on this blog; I also am a blogger, and I was wanting to
    know your situation; many of us have created some nice methods
    and we are looking to swap methods with other folks,
    why not shoot me an email if interested.