An Interesting Bias in xWOBA

I’d like to highlight a bias within xWOBA that could possibly be accounted for to improve the metric. In my view, however, the more interesting takeaway is the “why” behind what is happening and how this might be used from both a player evaluation and player development perspective.

The bias in xWOBA is found in the amount of backspin on hit balls. For spin, I created an expected distance model based on Exit Velocity (EV), Launch Angle (LA), and Horizontal Hit Direction or Spray Angle. This model has been helpful in assessing whether players should hit with backspin (article here) as well as changes to the ball and the amount of drag (article and model here). Alan Nathan and Tom Tango have pointed out that very-high-spin balls actually have increased drag and less distance. However, what happens at the high end of the spin spectrum does not interfere with the low end; thus, the general conclusions that follow would appear to remain valid. Additionally, while knowing actual spin values might help confirm the findings, it’s not just the spin rpms that are relevant, as the spin type (based on the spin axis) must also be considered. Rolling all this information up into an overall player average for a comprehensive cost/benefit analysis will likely prove challenging as spin axis values don’t average well.

The general takeaway from the research on whether players should hit with backspin is that backspin balls outperform expectations but the players that hit backspin balls more often actually underperform. That may seem a little counterintuitive at first; however, this relationship is clearly visible in the xWOBA player averages based on the data: Read the rest of this entry »


Using Objective Feedback to Drive Hitting Programming and Evaluate Progress at LSU Shreveport

The Louisiana State University Shreveport Pilots are an NAIA team in Shreveport, Louisiana competing in the Red River Athletic Conference. This article was written by Brent Lavallee and David Howell. Brent Lavallee is the Head Coach of the Pilots and David Howell is the Director of Player Development, Director of R&D, and Assistant Pitching Coach.

Introduction

With the rise of affordable bat sensors, we no longer have to rely on only the eye test when it comes to evaluating swings. Gone are the days of attempting to evaluate a hitter’s progress based on the small sample of fall games, or how well they seem to be hitting flips at the end of the season. Even the days of measuring exit velocity during tee work with a radar gun are comparatively basic with what can be accomplished with a sub-$200 Bluetooth sensor.

Blast sensor attached to the knob of a bat.

At LSU Shreveport, we started using Blast Motion sensors this fall, which are placed on the knob of a bat and measure metrics such as bat speed, attack angle, rotational acceleration, and more. The sensors work by taking into account the characteristics of a bat (length, weight, etc.) and derive swing metrics when hitters make contact. Read the rest of this entry »


Spin Trends by Pitching Staff

With the 2019 season firmly in the books and the expanded offering of spin-related pitching data now readily available across the internet, I decided it was time to take a hard look at every team’s pitching staff. The hope in doing so was to identify a trend, if any, within the spin metrics of the best clubs. Do any staffs have a noticeable tendency to use pitchers with a specific spin profile?

To answer this, I pulled together every pitcher and their average spin metrics for each pitch type that they threw a qualified amount of times (30-plus in most cases) in 2019. This meant ignoring splitters because of sample size considerations. I was also tempted to use Bauer Units — a proxy for spin rate divided by velocity, as well as a nod to Trevor Bauer — to control for velocity in this study, but I decided to keep this post more straightforward. The study instead uses raw spin rate, horizontal and vertical movement, and spin efficiency as reported by Baseball Savant. I then aggregated the players’ data by the team they finished the season with to create an average spin profile for every team. This team profile weighs all of their qualified pitchers equally.

Once I was able to establish what the normal team looks like across those categories, I wanted to identify any clear outliers to possibly show where organizations consciously emphasized certain metrics. To do that, I produced league rankings and standard deviations for each category based on the team averages. Read the rest of this entry »


2019 MVP Winners as Voted by Dead Sportwriters

“Alex Bregman is the runaway AL MVP for 2019” – MVP voters from the 1950s & 1960s

“Mike Trout finishes a disappointing 5th in 2019 AL MVP voting” – MVP voters from the 1960s & 1970s

“Christian Yelich is the near-unanimous 2019 NL MVP” – MVP voters from the 1980s & 1990s

“Xander Bogaerts narrowly misses the 2019 AL MVP” – MVP voters from the 1960s & 1970s

The Evolving MVP Voter’s Criteria

The winner of the MLB MVP awards is a function of two factors: How the players performed, and how the electorate evaluated that performance.

Much attention is paid to how players perform and how they stack up historically to peers from different eras, but for MVP selection, little attention has been paid to how the electorate has changed and shifted the definition of the Most Valuable Player.

Since 1931, the Baseball Writers Association of America (BBWAA) has voted and awarded each league’s MVP award. Over this period of time, the world’s understanding of player performance and what contributes to winning has changed dramatically. The 1931 voters probably looked at home runs, RBIs, and batting average leaderboards printed at year-end in their daily newspaper before filling out their ballot. That’s not to accuse them of being narrowly minded, it was just all they had available to them and all the baseball world knew to look at.

On the other hand, the 2019 voter (hopefully) spent at least a few minutes on FanGraphs or a similar site looking at things like WAR, wRC+, and DRS, and at best also considered advanced Statcast data and maybe even built their own AI-powered simulations to model a season without the player to see how much worse their team performed. At least, that’s what I would do if I had a ballot, and that’s what I would call “responsible voting” in 2019. Read the rest of this entry »


The Brief But Brilliant Pitcher

With the regular season over, my routine Baseball-Reference wanderings brought me to the JAWS rankings for pitchers. I had been tracking a handful of current players throughout the year and I wanted to see where they’d finished up. Before getting very far, however, I was quickly reminded that there’s a lot to be desired when it comes to pitcher recognition in the Hall of Fame. Why is it that owners of some of the best pitching seasons of the twentieth century have been left out of the Hall of Fame? Surely there is a level of brilliance that eclipses brevity and manages to leave an indelible mark in baseball history.

Sandy Koufax is a prime example of this. He had just six seasons of 100-plus innings where he had an ERA+ over 106, accumulating 48.9 career WAR and 46.0 peak WAR for a JAWS score of 47.4, far short of the Hall of Fame averages of 73.2/49.9/61.5 for starting pitchers. In a vacuum, one could view his JAWS numbers and dismiss his career as good but not worth of the Hall of Fame. But we don’t live in a vacuum. Despite falling short across the JAWS board, Mr. Koufax was nevertheless inducted in his first year of eligibility by appearing on a healthy 86.9% of ballots due to the fact that his final four years were the greatest final four years by a pitcher in baseball history. In terms of WAR, they each rank among the top 220 pitching seasons since 1920, with his 1963 and ’66 seasons ranking 13th and 22nd best of all time, respectively. Averaging 24 wins, eight shutouts, 298 innings, 307 strikeouts, and 9.1 WAR, these seasons have come to define the era. The 1972 baseball writers understood that his brilliance outshone his brevity when they voted him in.

However, while Koufax may be the archetype of the brilliant but brief ace, he was an outlier only in terms of how his meteoric career was recognized by Hall of Fame voters. When sampling the 250 greatest pitching seasons by WAR since 1920, did you know that only 43% of them belong to Hall of Famers? As a basis of comparison, 61% of the 250 greatest position players’ seasons by WAR since 1920 belong to Hall of Famers. These differences become even more stark as we narrow down to the 100, 50, 25, and 10 greatest seasons and exclude not-yet-eligible players, players connected to steroid allegations, or players banned from the game (Pete Rose). Read the rest of this entry »


The Effects of Repeating Pitches on Pitcher Success Rate

It’s the bottom of the sixth inning at Minute Maid Park. Down 3-2 in the series and facing elimination, the Yankees are trailing the Astros, 4-2, in Game 6 of the 2019 American League Championship Series. Facing Yordan Alvarez with two out and nobody on, Tommy Kahnle needs to keep the game within reach to give his offense a shot at coming back. After falling behind 2-0 to Alvarez, Kahnle comes back and gets a strike looking on a changeup up in the zone. On 2-1, Kahnle throws a changeup below the zone and gets Alvarez to swing through it for strike two.

After getting a swinging strike and with the count now at 2-2, what does Kahnle do to try to get Alvarez out? Does he attempt to repeat the previous pitch after successfully inducing a swinging strike, or does he throw a different pitch in anticipation that Alvarez is expecting the same pitch? Kahnle repeated the changeup below the zone and got Alvarez swinging on strikes to keep the Yankees within two runs.

Pitch sequences like these are very intriguing because of the variety of factors that affect the at-bat, such as the pitcher and hitter’s game plans, game situations, and recent performance. It is a big reason organizations carefully study pitch sequencing. I wanted to quantify and analyze the effectiveness of situations like Kahnle’s against Alvarez. That is, I wanted to determine the most effective two-strike strategy for the pitcher after the batter swung and missed on the previous pitch. Organizations can then share these findings with their pitchers so that they have better success as a staff. Read the rest of this entry »


Reflecting on the Cubs’ Five-Year Run

Last month at The Athletic, Patrick Mooney and Sahadev Sharma took a deep dive into the Cubs’ successes and failures from 2015 through the conclusion of 2019. This led me to reflect upon this five-year run and try to figure out if, on the whole, it should be considered a success. They famously broke the franchise’s 112-year World Series drought, yet this Cubs team has seemed to leave baseball fans (especially Cubs fans) wanting more. When they took the league by storm in 2015 to the tune of 97 wins (a meteoric 24-win increase from the previous season), the baseball community was not asking if this group would win a World Series, but when. After the 2016 championship, we spent all offseason dreaming about how many World Series this group could claim over the next five years.

Of course, this Cubs group has yet to win another ring. Joe Maddon has left. Trade rumors have been swarming around the likes of Kris Bryant and Kyle Schwarber following reports of the Ricketts wanting to cut payroll. How do the Cubs pivot after this lost season? How much longer does Theo Epstein have to turn this ship around? These are the existential questions being asked in and around Wrigleyville after this season’s second-half collapse.

However, I would argue these questions are not totally fair. This Cubs core of Bryant, Anthony Rizzo, Javier Baez, and Jon Lester has led the team to post one of the best five-year runs in the National League since the inception of the Wild Card in 1994. The Cubs were swept in the NLCS in 2015 at the hands of the Mets, won the World Series in 2016, lost the NLCS in five games to the Dodgers in 2017, lost in the wild card game to the Rockies in 2018, and missed the playoffs this year. Those regular seasons, in order, consisted of 97, 103, 92, 95, and just 84 wins this past season. Simply looking at the playoff and regular season results, this does not feel like a completely dominant stretch of baseball. Read the rest of this entry »


2019’s Quietest Breakout

The 2019 Reds were an enigma. They had the firepower, led by the homer-happy Eugenio Suarez. They had the rookie sensation, Aristides Aquino, who dingered like it was nobody’s business. On the pitching side, they had a steady crop of reliable pitchers. Sonny Gray was the unquestionable ace of the staff while the quartet of Raisel Iglesias, Michael Lorenzen, Amir Garrett, and Robert Stephenson anchored the pen. Despite all that, they finished with a lowly 75-87 record, 16 games behind the first-place Cardinals.

Going into 2019, no one would have guessed how pivotal of a role Stephenson, 26, would have played. He came into the year with a career 5.47 ERA, a 5.50 FIP, and a 1.673 WHIP over the past three seasons. His career was clearly at a crossroads; He was a former top prospect who hadn’t shown sustained success at the major-league level. He spent much of 2018 in the minors, regaining his mojo, pitching to a 2.87 ERA in 20 starts with the Louisville Bats, Cincinnati’s Triple-A affiliate.

The Reds announced at the end of spring training that Stephenson would start 2019 out of the bullpen. Since Stephenson was out of options, this year was most likely the last chance he would get in Cincinnati. It became a make-or-break, sink-or-swim, pitch-well-or-ya-gone type of campaign. Despite all of the stress and lack of previous MLB success, Stephenson engineered one of the most unheard and unlikely breakout seasons in 2019.

His Baseball Savant page is a thing of beauty. His xBA, xSLG, hard-hit percentage, and xwOBA all rank in the top 5% of all pitchers in 2019, while his strikeout percentage, fastball velocity, and exit velocity against placed him in or over the 25th percentile. Read the rest of this entry »


How the Nationals Outsmarted Paul Goldschmidt in the NLCS

The NLCS had a weird feel to it from the get go. The Nationals’ pitching was stupendous, balls hit off the bat that sounded like towering home runs were dying on the warning track, and of course, the Cardinals bats never woke up. This was a bit unexpected considering the club’s monster first inning in Atlanta during game 5 of the NLDS. We were all waiting for the Cardinals offense to appear, but it never showed up, as they only scored six runs in a four-game sweep by the Nationals.

Nobody could seem to get anything going offensively. Instead of searching for answers for all the Cardinal batters, let’s just look at one. While Paul Goldschmidt had his worst season offensively with a .346 wOBA, he is still the thunder in the St. Louis lineup. How exactly did the Nationals pitch to Goldschmidt, and why couldn’t he succeed in the series?

On one hand, the Nationals pitchers were outstanding. They were putting pitches right on the edge of the plate and mixing their pitch selection well. When you have Max Scherzer, Stephen Strasburg, and Patrick Corbin in your starting rotation, your opponent is going to have a difficult time. Additionally, Anibal Sanchez had a great game. Meanwhile, Goldschmidt went 1-for-16 with nine strikeouts in the series. He did seem to experience a little bit of bad luck with a few hard hit balls. In Game 4, he hit a ball 101.4 mph that went 340 feet, and he had another two hard-hit outs in Game 2. One traveled 316 feet that was hit 95.9 mph off the bat, and another traveled 284 feet that was hit 108.1 mph. That may not make him feel tons better about his performance given the nine strikeouts.

It is not surprising that Anibal Sanchez was able to succeed in his three times facing Goldschmidt in Game 1. Sanchez used the cutter and sinker well in that game. While his sinker generated an unimpressive .387 wOBA this year, his cutter was lethal with a .260 wOBA. Goldschmidt had a .350 wOBA against sinkers and a .317 wOBA against cutters. Those numbers are going to add to some underwhelming results. Sanchez utilized the sinker and cutter well and put them in difficult locations against Goldschmidt. During the second at-bat, Sanchez generated similar results. Read the rest of this entry »


Is Zack Greinke Throwing Too Hard?

Before Game 3 of the ALDS, Zack Greinke answered eight questions in just 67 words. The former Cy Young winner would soon be starting his 12th career postseason game. Earlier in the season, Greinke had been the main piece in the biggest deal of the deadline, joining the Astros and making them almost unanimously the best team in the league. Fifteen of the 32 FanGraphs writers who made a prediction on the World Series winner chose Houston. On July 30th, the Astros had a 24% chance of winning the World Series. On July 31st, that number had increased to 26.4%. To put that in perspective, the Nationals had a 4.7% chance.

However, Greinke will be the first to tell you that with success and high expectations comes media attention. Greinke had gone from an overperforming and small-market Arizona Diamondbacks team to an absolutely stacked Astros team. Houston was “World Series or bust,” especially now that they had sacrificed some of their future for Greinke. Before Game 3, the media crowded around Greinke to try to get answers and information about the big game. He did not oblige. They got eight answers but not much information from any of them.

One of those answers stated that the game was just a normal game. However, for Greinke, his performance was anything but normal. During that contest, Greinke would surrender six runs in 3.2 innings. Greinke’s mental ability to deal with a postseason game and the pressure that comes with it was questioned and became a major storyline due to the interview. In Game 1 of the ALCS, Greinke gave up three runs in six innings, which isn’t bad considering the Yankees lineup. However, for Zack Greinke, it is disappointing, frustrating, and it continues a recent narrative that he cannot handle the postseason. The postseason comes with a lot of added pressure and adrenaline, which can sometimes cause pitchers to throw harder. However, this is not always a good thing, as we have seen this year with Greinke. Read the rest of this entry »