Baseball BeatJanuary 25, 2010
Graphing the Hitters: Plate Discipline
By Rich Lederer

I introduced Graphing the Hitters earlier this month. The focus was on Productivity, defined as OBP and SLG.

In this week's edition of Graphing the Hitters, I'm going to concentrate on Plate Discipline. The graph below plots walk rate (BB/PA) on the x-axis and strikeout rate (SO/PA) on the y-axis for every qualified batter in 2009. The intersection of the MLB averages for BB% (8.88%) and SO% (17.96%) created quadrants that classify players as better-than-average in both (lower right), worse-than-average in both (upper left), or better-than-average in one and worse-than-average in the other (lower left and upper right).

Unlike Fangraphs, I believe the denominator for strikeout percentage should be plate appearances (rather than at-bats). For whatever reason, Fangraphs defines walk percentage as BB/PA but strikeout percentage as SO/AB. As a result, while the raw numbers were downloaded from Fangraphs, the BB% and SO% were calculated separately.

Note: You can download a spreadsheet containing the PA, BB, SO, BB%, and SO% of the 155 hitters here. This information can also be used to locate the 134 players not labeled in the graph below.


My first question following the Productivity graph was "Is Albert Pujols any good?" Well, after looking at the Plate Discipline graph, I've got to ask the same question once again. This time around, I'm going to shout out my question.


OK, I think I've made my point now. Not that it was really necessary. Everybody already knows that Pujols is better than good. I mean, this guy is great. In fact, he is on pace to become one of the greatest hitters of all time and perhaps the best or second-best righthanded hitter ever.

Pujols has played nine seasons in the major leagues. He has ranked in the top ten in batting average, slugging average, on-base plus slugging, total bases, and times on base every year. What is less known is that Albert has improved his walk rate every single season while reducing his strikeout rate by a third since his rookie campaign in 2001.

In 2009, Pujols had the sixth-highest BB% (16.43%) and the ninth-lowest SO% (9.14%). That is a remarkable combination. He was the only player in the top 50 in walk rate with a strikeout rate below 10.0%. You have to go all the way down to No. 57 in the walk rankings to find someone with a lower strikeout percentage (Dustin Pedroia). The Red Sox second baseman had the lowest SO% (6.30%) in the majors.

Pujols and Pedroia are two of only 13 qualified hitters with more walks than strikeouts.

First Last Team PA BB SO BB/PA SO/PA
Adrian Gonzalez Padres 681 119 109 17.47% 16.01%
Nick Johnson - - - 574 99 84 17.25% 14.63%
Chipper Jones Braves 596 101 89 16.95% 14.93%
Albert Pujols Cardinals 700 115 64 16.43% 9.14%
Todd Helton Rockies 645 89 73 13.80% 11.32%
Marco Scutaro Blue Jays 680 90 75 13.24% 11.03%
Joe Mauer Twins 606 76 63 12.54% 10.40%
Luis Castillo Mets 580 69 58 11.90% 10.00%
Victor Martinez - - - 672 75 74 11.16% 11.01%
James Loney Dodgers 652 70 68 10.74% 10.43%
Dustin Pedroia Red Sox 714 74 45 10.36% 6.30%
Yadier Molina Cardinals 544 50 39 9.19% 7.17%
Alberto Callaspo Royals 634 52 51 8.20% 8.04%

Adrian Gonzalez led MLB in walk rate and walks (119) last year. He was one of five first basemen with more walks than strikeouts. Three second basemen, three catchers, one shortstop, and one third baseman also accomplished this feat, including three projected starters for the Boston Red Sox in 2010 (Marco Scutaro, Victor Martinez, and Pedroia). The St. Louis Cardinals are the only other team with more than one representative (Pujols and Yadier Molina).

At the other end of the spectrum, Yadier's older brother, Bengie Molina, had the lowest BB% (2.50%) in baseball. Bengie struck out in 13.08% of his plate appearances, which means he whiffed more than 5x as often as he walked.

Mark Reynolds had the highest SO% (33.69%). He set a single-season record with 223 strikeouts in 2009. The 26-year-old third baseman has played three seasons in the majors and owns the top two strikeout totals in the game's history. His SO and BB rates have increased each year. The good news is that his BB% has risen 29.2% while his SO% has advanced just 8.0% since his rookie campaign in 2007.

Russell Branyan (29.50%), Jack Cust (30.23%), Adam Dunn (26.50%), Ryan Howard (26.46%), Brandon Inge (26.69%), and Carlos Pena (28.60%) stand out for their high strikeout rates. However, Inge was the only one with a walk rate (8.48%) below the league average.

Lastly, there were 13 qualified hitters with walk rates over 15%. Other than Pujols, every player in this baker's dozen bats lefthanded or both. Therefore, I believe it is safe to say that the three-time MVP is truly unique. As the graphs have shown, Pujols is the most disciplined and productive hitter in the game today.


Pujols is nearly too good to be true. I think I've been fooled one time too many to buy him as "legit".

Sad, isn't it?

"For whatever reason, Fangraphs defines walk percentage as BB/PA but strikeout percentage as SO/AB"

I love FanGraphs, but I never understood why they do this. I pretty much ignore their K% stat as a result of this, because I don't understand why this equation is used. Does anybody know why they calculate it in this fashion?

Did you take out intentional BB's? I think that'd make a decent difference in guys like A-Gonz or Pujols' BB rate.

No, I did not remove IBB. If you don't count IBB, then you have to exclude those PA as well.

In an essay on baserunning in the Bill James Handbook 2010, Bill argued vehemently that "every event should be included." Infield hits, slow runner on base ahead of you? He doesn't care. Bill admits that there are "outside influences on the data." But he responds by saying, "There are outside influences on ALL data." It is an eloquently written rebuttal to those who would include this but exclude that when analyzing stats.

In Moneyball, Michael Lewis wrote about James, "[He'd rather leave] an honest mess for others to clean up than a tidy lie for them to admire."

As it relates to IBB, a walk is a walk. They all count. Some walks are more intentional than others. Some are less intentional than others. Many walks can be attributed more to the pitcher. Many can be more attributed to the hitter. There are intentional walks and there are unintentional intentional walks. For the most part, I believe the hitter earns an IBB. It's not just something that is granted him. As a result, I feel comfortable including IBB in the totals.

By the way, did you know that, according to the MLB Rule 10.14, "the official scorer shall score an intentional base on balls when the pitcher makes no attempt to throw the last pitch to the batter into the strike zone, but purposely throws the ball wide to the catcher outside the catcher’s box."

In other words, a BB counts as an IBB if the final pitch thrown in the at-bat is an intentional ball, even if not all the pitches are intentional balls. As such, if a batter like Pujols draws two or three balls and the opposing manager decides to put him on base by throwing one or two more wide ones, that BB is scored as an IBB. If we exclude that event from his total BB, then I think we are really playing with the numbers and doing a disservice to Pujols and the data overall.

Honorable mention to Miguel Olivo, the king of impatience, with his strikeout rate of 30.29% and walk rate of 4.57%. At 416 PAs, he did not qualify for your list, but he deserves mention.

(Rockies fans, take heart: That walk rate actually represents a substantial INcrease for Olivo.)

Thanks geo. With 126 SO and only 19 BB, Olivo's SO/BB ratio of 6.63 is horrendous. His BB rate was a five-year high. As such, he actually improved upon his 6.97 career SO/BB ratio. He has had three seasons in which his SO/BB was at least 10. Yikes.