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Talkin' Sabermetrics: Paredes' Walk Rate and A Logical Fallacy About Sac Bunts

 Jimmy Paredes on the base paths at the ML level last year. (Photo by Norm Hall/Getty Images)
Jimmy Paredes on the base paths at the ML level last year. (Photo by Norm Hall/Getty Images)
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Jimmy Paredes has enjoyed a fine offensive season in Oklahoma City, and it's not surprising that fans would clamor to see the young athletic second baseman/outfielder called up to the big club. At this point, it appears that Paredes' call up will not occur until sometime in September, when the rosters have expanded. Over the last few months, when Jeff Luhnow has mentioned Paredes, he lauds his talent but usually adds a statement about Paredes' need for continued development.

Undoubtedly, Paredes' late shift to the center field position has something to do with delaying his call up until next month. But I also think that a sabermetric issue--specifically Paredes' walk rate--may hold the reason that Paredes needs further development in order to enhance his chances of success at the ML level.

Consider this response about Paredes given by Luhnow in a chat on May 22:

Jimmy is hitting for a high average, but he still has some work to do (look at the walks and strikeouts). He’s a big league prospect and his time will come.

At other times, Luhnow has mentioned Paredes' need for continued development in pitch selection, which is another way of saying plate discipline.

In 179 PA at the ML level last year, Paredes posted a 5% BB rate and a 26% K rate. Those are poor plate discipline results. In 511 PA in AAA this year, Paredes showed an improvement in K rate, 19%, but his BB rate declined to 4.1%. Though the improvement in strike outs is a good sign, it is still high for a player with that low a walk rate and limited power. The ratio of walks to strike outs is poor, though marginally better in AAA this year.

The combination of a very low walk rate and a high K rate is generally a weak profile for major league success. One can point to Jose Altuve's ML success, despite a low walk rate; but Altuve's walk rate over his career generally is better than Paredes' rate, and, more importantly, Altuve has outstanding contact skills. Paredes' respectable wRC+ at the ML level last year (94) and above average wRC+ in AAA this year (110) is driven in part by unsustainable BABIP of .380 in the majors last year and .370 in AAA this year. Paredes may be capable of sustaining a high BABIP, but most likely not higher than .330 - .340 in the majors. This means that a regression in his BABIP would make his offensive stats far less attractive.

I used Fangraphs' filters to illustrate the importance of BB rate for Paredes' future. First, I screened all age 21 - 25 major leaguers (min. 250 PA) from 2000 - 2012 who meet criteria that fall within Paredes' statistical range playing in AAA and the NL: BB Rate Less Than 6%; K Rate More Than 20%; BABIP Greater Than .330; and SLG% between .390 and .460.

Next, I changed only the BB rate, above, to Greater Than 6%, to reflect a profile for Paredes if he improved his BB rate.

Using the profile with less than a 6% BB rate, which is reflective of Paredes' current profile, only one player age 21 - 25 meets the criteria during the 12 year period: Chris Johnson. Chris Johnson is a useful hitter, but he is hardly a high ceiling player. The paucity of young hitters fitting Paredes' hitting profile who were able to make it to the majors and show some success with a very low walk rate is a red flag. (If the K rate is lowered somewhat to 18%, by the way, one more batter is added to the list---Alex Presley.)

If the Paredes profile is improved to reflect all 21 - 25 hitters with a BB rate above 6%, the list expands to 13 players. The players include: B.J. Upton, Dextor Fowler, and Brad Wilkerson among the higher tier BB rate hitters; Chase Headley, Curtis Granderson, and Austin Jackson among the mid-range BB group; and Mike Carp and Chris Davis as the lowest tier above 6%.

Paredes' current combination of very low walk rate, high strike out rate, and low-to-medium power, does not portend a high liklihood of success at the ML level. I'm not saying that Paredes is a bad prospect. He is only 23 years old, and he still has time to improve his plate discipline profile. His athletic tools are a good reason to put a high priority on his continued development. But there was good reason to place Paredes in AAA, rather than the major leagues this year.

A Logical Fallacy About Sacrifice Bunts

Tango at The Book blog does a pretty good take down on a blog piece attacking the sabermetric critique of sac bunting. The target is an article called "inconvenient truth about sacrifice bunts," which throws down the gauntlet with "Stop the presses....that 'everything you know is wrong' twaddle that the neo-sabe movement has been overselling is ready to take one on the chin." A broad claim like that makes you think that we will be enlightened to find that giving away outs is a winning ticket.

I'm not writing this as an evaluation of the pros and cons of the sacrifice strategy. Sabermetrics is rightfully skeptical of the overuse of sacrifice bunting. For many years, sacrifice outs were handed out like candy in situations when their use would reduce the team's run expectancy. However, modern sabermetrics recognizes that there are some situations when sacrifice bunts are useful, and may well be justified occasionally in a game theory sense. So, I don't really agree that sabermetrics is as rigidly anti-bunt as the "inconvenient truth" author says.

My interest here is more about Tango's effectiveness in identifying the logical fallacies in the article.

The article says that sabermetrics fails to look at the winning percentage of games in which the sac bunt is employed. The author says "what is so shocking" is that the win-loss record is so good, "more than good, in fact." The winning percent for teams that employ the bunt one or more times in a game is 64%, which evidently proves that it is a winning strategy. The conclusion is that the sac bunt is associated with an elevated winning percent. The author goes on to argue (rather unclearly, in my view) that sacrifice bunts are neutral game elements.

Tango should have begun his response with Samuel L. Jackson's "Well allow me to retort."

First, as the article itself notes, sac bunts are more often used by a team that is already winning than one that is on the losing end of the current score. (62% of sac bunts in non-tie situations are undertaken when a team has the lead.) If the bunting team already had a lead in the game, is it any surprise that the team shows a winning record, given this advantage? As Tango says, "sac bunts happen to occur when the team already has a good chance of winning."

Next, Tango addresses the article's claim that more runs are scored when teams use the sac bunt:

That is, in the PA of the sac bunt, and all PA that follow, the average team scored 1.031 runs.

How is that possible? Well, if we look solely at the base-out situation presented, and regardless of whether the batter bunts or not, we expected 1.058 runs to score. So, this is why we get a lot of runs scored in innings when you have a sac bunt: it’s because you happen to have a runner or two already on base! And in Table 11, we get to the blogger’s point. We see that following a sac bunt, the team wins 62.8% of the time. But before the sac bunt, based on the inning, score, base-out, the chance of winning was 63.8%. (emphasis added)

Tango goes on to point out several other plays where the same fallacy of "association with winning" exists. For example, a team wins 56% of its games after a caught stealing. But this doesn't mean that getting caught stealing is a good thing. It just reflects the fact that teams which have a lead are more likely to attempt a steal. Receiving an intentional walk is the event with the highest subsequent winning percentage. Again, one of the main reasons is that a batting team receives an intentional walk most frequently when it is already heavily favored to win.

Oh, by the way, Astros' manager DeFrancesco said that Scott Moore's sac bunt in the first inning of Sunday's game was Moore's idea, according to a Zachary Levine tweet. It's almost like Tony D doesn't want a sac bunt to be his first introduction to Astros' fans.