Just the mention of Keith Hernandez should have clued you into questions like these you are bound to receive–Hernandez #7 and no mention of Don Mattingly? Especially when considering peak value–he certainly had a higher peak than Hernandez.

Mattingly, in fewer AB, had more doubles, HRs, RBI, TB, along with a higher BA and SLG.

Neither deserve to be elected, but why is Hernandez and not Mattingly on the list? Is it the lack of actual pennants won?

–Lou Poulas

There are two main things that distinguish Hernandez from Mattingly offensively:

  • Hernandez's giant lead in walks, 1070 to 588.
  • Hernandez's longer career. While the two have similar rates of offensive production over their careers, Hernandez has a season-and-a-half's worth of plate appearances on Mattingly.

For what it's worth, my method does not rate Mattingly's peak as superior to Hernandez's. That's because it doesn't define peak as some arbitrary small number of seasons. While Mattingly's best four seasons are better than Hernandez's best four, Hernandez had ten seasons worth more than five wins over replacement offensively (by my numbers); Mattingly had only four. The Pennants Added method recognizes that each of those ten seasons (and all of the players' other seasons) contributed something toward their teams' chances of winning the pennant. It doesn't ignore them just because it they fall outside of the player's best N seasons, for some arbitrary N.

That said, the extra "peak" value doesn't make much of a difference one way or the other in the comparison between these two players. The main differences are the walks and career length.

–Michael Wolverton


I enjoyed reading your last two pieces on the 4-man rotation. In today's article, you show numbers for 160 starters from 1978 to 2001 who pitched at least eight times on both 3 and 4 days rest. I have a couple of questions regarding that chart.

  1. I would imagine that 3-day rest starts were more common at the beginning of your period than at the end. For example, a pitcher in the sample from 1978 might have 25 3-day rest starts and 10 4-day rest starts, while a pitcher from 2001 might have 10 3-day rest starts and 20 4-day rest starts. So you would have more starts and innings from the early part of the period in the 3-day rest start group and more from the late part of period in the 4-day rest start group. Since offense was substantially lower in the early part of the period than in the late part, a pitcher's numbers would look better in the 3-day rest sample because of this bias.
  2. I wonder whether this bias is the reason for the higher K/9 and HR/9 rate in the 4-day rest sample, rather than not "let[ting] their defense work for them."


You make a very good point, and I was remiss not to account for this bias in my original study. (I did point out that the majority of pitchers in the study had lower ERAs on three days' rest than on four, and since that comparison had the same pitcher-seasons in each group, there was no potential for bias.)

The reason I did not try to account for the increased offensive numbers of the last 10 years was that so few pitchers in the study were affected by it.

Of the nearly 30,000 innings in the study, less than 900 of them–just 2.8% of the total–were thrown since 1993, when the modern hitters' era began.

Still, if we look at the innings in each group–those thrown on 3 days rest and those thrown on 4 days rest–there is a small difference in the distribution of those innings. Of all the innings in the study thrown through 1985, 47% were made on 3 days' rest. Since 1986, only 42% were made on 3 days rest.

Is this enough to change the conclusion of the study? I tried to alter the study to find out. Whereas, in the original study, I simply summed all the innings for all the pitchers in both groups, this time I calculated each pitcher's "average start" for the season in question.

For example, Phil Niekro made 32 of 40 starts on just three days' rest in 1978, while Denny Neagle made just 8 of 25 starts on three days' rest in 1995. The original study would end up with 40 starts in the three days category, and 25 starts in the four days category–but 32 of the 40 starts on three days rest came in the low-offense 1978, while 17 of the 25 starts on four days rest were thrown in high-octane 1995.

For the new study, Niekro's performance in 1978 would be whittled down to a single start in each category–that is, his numbers on three days' rest would be divided by 32, while his numbers on four days' rest would be divided by 8. The same adjustment was made for every pitcher in the study, so in the end we should end up with 160 matched pairs, with exactly the same number of adjusted starts in each group.

After making that adjustment, here are the new numbers:

Rest     IP   H     ER   BB   K  HR   ERA   H/9  BB/9  K/9   HR/9
3 days  1097 1046  442  343  603  87  3.62  8.59  2.81  4.95  0.71
4 days  1076 1055  467  344  602  93  3.91  8.83  2.88  5.03  0.78

As you can see, the rate numbers barely change at all. Pitchers still show a nearly 30-point improvement in their ERA on less rest, and they still show increased command (fewer walks per 9 innings) and increased sink on their pitches (fewer homers per 9 innings).

So to answer your question: yes, there is some bias in the original study. But accounting for it doesn't change the conclusion at all.

–Rany Jazayerli


I was looking at the list for the teams, and I noticed that there were eight instances where a team on the plus side was in the same league/season as a team on the minus side. I was curious if there was any way to determine how much of the variance for those two teams was contributed just by the season series. For example, look at the 2002 season series between Minnesota & KC. Minnesota has won 12 of 16, yet I believe we have been outscored by KC by 3 runs. This should influence the Pythagoreans for both teams by 4 wins.


Parts of these are easy to calculate, thanks to the good folks at Retrosheet who have put the score for every game played since 1900 online.

Here are the matches:

  • 1905 AL Det StL

    So far so good. Detroit won the season series 13-9, but was outscored 86-76. Detroit had 5 one-run wins to the Browns 2, while the Browns had 5 blowout wins (6-0, 9-4, 9-0, 8-1, 11-0) to the Tigers 2 (10-1 and 8-1). That's worth ~3.5 wins per team.

    These two teams are a good match in another way. The Browns scored 509 and allowed 608, while the Tigers also allowed 608 and scored 511–just two runs more. The Tigers won 25 more games.

  • 1917 NL StL Pit

    Less well here, but still the Cards went 14-8 with only a 72-64 run advantage. Worth about 3 wins.

  • 1924 NL Brk StL

    Great example. St Louis outscores Brooklyn 127-107, yet goes 7-15, which explains more than 6 games in the Pythagorean errors. Three St. Louis wins were by scores of 17-0, 17-3, and 12-0 – that makes a difference of 3 games right there.

  • 1932 NL Pit NYG

    Pitt goes 15-7 on a 110-98 margin. 2.7 games explained.

    1946 AL Wash Phi

    Washington goes 16-6 on 97-91. 4.3 games.

  • 1955 AL KC Det

    Tigers only go 12-10 despite outscoring KC 170-100. 6.2 games. Tigers had wins of 10-2, 16-0, 10-1, 10-1, 17-1, 11-6, 8-3, 8-2; KC never won by more than 4, and was 5-0 in the one-run games.

  • 1970 NL Cin Chi

    Once the leagues expanded and common games dropped, the feat became harder to accomplish. Nonetheless, the Reds and Cubs dropped two games to Pythagoras when the Cubs "only" went 7-5 with a 75-48 run margin.

  • 1984 NL NYM Pit

    And here, where the Mets went 12-6 despite being outscored 57-52, is another 4-game turnaround. Two Pirate wins, 11-0 and 14-4, stand out; no other game in the series had more than a three-run difference.

–Clay Davenport


I think the support neutral stats you post are terrific and I consult them frequently. However, I had a question regarding the updated stats for September 1st. I noticed that a lot of the numbers changed considerably. For example, Derek Lowe was at the top of the list yesterday with an SNWAR of 6.7. Now, his SNWAR has dropped to 6.4, and he has dropped to third place despite the fact that he didn't pitch yesterday. Pedro Martinez also dropped a bit, and Randy Johnson went up quite a bit. Neither of them pitched yesterday either. So my question basically is, what happened?


The answer is that I finally got around to updating the park effects. Fenway had been listed as a hitters' park previously, but it's actually been playing as a pitchers' park (neutral after the DH "ground rule" is taken into account) the past two years. So Lowe and the other Boston starters dropped a little. The BOB has been playing as a pretty extreme hitters' park the past two years, so Randy Johnson's and the other Diamondbacks' numbers were bumped up a bit. The changes to the numbers were fairly small in all cases, but they were enough to make the slight changes in the standings you noted.



Isn't the elimination of draft pick compensation for free agent signings going to be a disaster for small market clubs? Last offseason, the A's lost Jason Giambi, Jason Isringhausen, and Johnny Damon to free agency, but that allowed them to restock their organization with 7 top 40 draft picks.

If Giambi, Isringhausen, and Damon were free agents THIS year instead of last, Oakland's future wouldn't look as bright, would it?

Without draft pick compensation, more small market clubs will be forced to trade their impending free agents during the season, in order to salvage some value for them. At the same time, the trade value of those players will be reduced because the teams trading for those players won't get the draft picks if they fail to sign the free agents.

Will the extra money the A's get via revenue sharing make up for the fact that they will NOT get draft picks as compensation when Chavez, Tejada, Mulder, Zito, Hudson, etc., depart via free agency?


I don't know that it's going to be a disaster, but it certainly isn't a welcome development. In the specific case of the A's, yes, it's a good thing that the A's received picks for the loss of Damon, Isringhausen, and Giambi, and if Ray Durham leaves without draft choice compensation, that's a bad thing.

I think you've clearly identified an effect of the new CBA, in terms of reduced leverage for "free agent sellers" around deal time. I don't know whether or not the revenue sharing money that will presumably flow to clubs in smaller markets (work with me…) will counteract the effect of not receiving draft pick compensation. Until we see it play out for a few years, we won't know for sure. Given that the new CBA is 4/5 years, we may not know until after the next CBA is in place.

–Gary Huckabay


I love your analysis of the game, but I wish you guys would stop shilling for the players in the labor debate. It's costing me money.

Like many Americans, I have a large portion of my wealth passively indexed against the S&P 500 stock market index. Thus, I am a partial owner of the Atlanta Braves (AOL Time Warner), the Anaheim Angels (Disney), the Chicago Cubs (The Tribune Company), the New York Yankees (The New York Times Company), and the Boston Red Sox (again, The New York Times Company), just to name a few. The profits from these ballclubs flow through to me, and thus I fully support management's current attempts to keep labor costs down.


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