Archive for Research

What Actually Makes a Curveball Effective?

The other day I began pulling together Savant data to determine whether there was an ideal zone percentage for different types of curveballs (CUs) and sliders (SLs). I haven’t found much on that front yet. However, I did realize that I don’t really know what makes curveballs effective, both from a results standpoint (extra whiffs, weaker contact, etc.) or a trait standpoint (vertical break, horizontal break, velo). I took a look at all of these factors for the curveballs in the 2019 baseball season to see if anything stuck out.

I analyzed a sample of 214 pitchers, representing everyone from 2019 who threw at least 20 innings, a curveball at least 10% of the time, and qualified for Savant’s pitch movement leaderboard. From this sample I pulled info on every pitcher’s spin profile, wOBA, xwOBACON, zone percentage, SwStr %, and RHB/LHB splits. I even noted all that same info for the rest of their arsenal as well as just to have a full view. Then they were bucketed in every way imaginable with averages and standard deviations to see which ones stood out. I do want to preface all my findings by saying that the sample size is not ideal, as the buckets were mostly of decent size (roughly 100-plus players), but I did get granular at times (the smallest group was 48).

I am most focused on the following metrics: CU wOBA, CU xwOBACON, CU SwStr %, CU Drop & Tail (as a % difference vs. the average pitcher at similar velocity). Here are the averages across the entire sample: Read the rest of this entry »


What Is a Run Worth?

I recently began thinking about how teams can know that they are efficiently spending their money, or where teams actually get the runs that they spend all their money on. With players signing massive contracts in the 2018-19 offseason, I began to wonder if any players were really worth that much money. The process begins with one big question: What is a run worth? I quickly realized that each team theoretically needs to manufacture the same number of runs as all the other teams do if they want a better chance to make the postseason. What is different from team to team is budget. This means that a run is worth a different monetary value to each team, and that each team would be willing to pay a different amount of money for the same number of runs. The problem is that to each player, a run costs the same amount, causing Billy Beane, played by Brad Pitt in the movie Moneyball, to claim that “It’s an unfair game”.

Figuring out what each team values their runs at would enable me to evaluate how efficient the signing of certain contracts was for each team and furthermore would allow me to figure out where the most value comes from in the payroll of a team. First, I had to figure out how to convert the basic statistics of a player into the number of runs that player actually contributed to the team. I eventually came across the Estimated Runs Produced statistic from the 1985 Bill James abstract. Below is the calculation.

ERP = (2 (TB + BB + HBP) + H + SB – (.605 (AB + CS + GDP – H))) .16

This is a stat created by Paul Johnson in order to obtain more accuracy than Runs Created, which he succeeded in doing. I then fired up R and ran some tests on team statistics to see how well it lined up with the actual number of runs that each team scored. I graphed ERP against Runs Scored first for every team dating back to the beginning of the 30-team era in MLB: Read the rest of this entry »


Did the Baseballs Carry More in 2019?

As much as baseball fans would like a simple explanation for the astronomical increase in home runs in 2019, it is becoming clearer that many factors have played into the surge. Among the possible reasons are batters prioritizing hitting homers more than ever before, pitchers having difficulty gripping the seams of the baseball, and of course the famous “juiced balls.” Last month, a committee released initial results of a comprehensive study attempting to determine the driving forces behind the home run rate growth.

I am particularly interested in the idea that fly balls were supposedly carrying more in 2019. On multiple occasions throughout the year, I listened to announcers observe that outfielders seemed to be severely misjudging fly balls. For instance, the center fielder would be drifting back toward the wall, as if he had a bead on it, and the ball would end up 15 rows deep. Although this may seem like evidence for increased carry of the baseball, such observations can easily be driven by confirmation bias. There was a tendency this year to believe that every ball in the air would be a homer, so when a ball would carry a lot, it fit with expectations and the belief continued to grow. It may just have simply been the case that the wind was blowing out that day, or that the batter struck the ball in a particular way, and the carry had nothing to do with the ball itself. To determine if the perception was in fact reality, I focus on the following question: Did similarly struck balls travel farther in 2019 than previous years? Read the rest of this entry »


Mariners Reveal Their Risk-Loving Nature with Evan White Contract

Do you like to gamble? The Seattle Mariners do. A lot. In fact, Seattle has chosen to introduce substantial risk into its relationship with Evan White this offseason, with little additional expected return. Given all of the action so far this offseason, you could be forgiven for paying little attention to this particular transaction back in November. But it’s an unusual type of deal that some analysts believe could become more common in future years, and it raises some thorny questions about financial risk management.

When I first read reports that some players were criticizing White — a 23-year-old first-base prospect who has never played above Double-A — for signing a long-term contract with the M’s, I was a little taken aback. My initial reaction to the deal had been the opposite: I couldn’t understand why the Mariners would lock themselves into paying a minimum of $24 million to a player who had never taken an at-bat in Triple-A, much less the majors, and who they would have had team control over through at least his age-29 or age-30 season (depending on when they call him up) in the absence of any long-term contract. If the Mariners simply played it year-by-year with White and he ends up being an above-average major leaguer — or even a star — they could expect to pay him somewhere in the range of $24 million through his six years of pre-arbitration and arbitration years. And if White ends up being a complete or near-complete bust (as is quite possible), the Mariners could have cut him loose while paying him a negligible sum.

And from White’s perspective, if he takes a cold, hard look at the numbers, the probability of him making less than $24 million in his career absent this contract is quite high. Some research indicates that the bust rate for hitters ranked in the bottom half of top 100 prospects and assigned an OFP of 55 on the scouting scale (as Baseball Prospectus did this offseason) is as high as 30-40%. If I’m Evan White, and I assess that there is a greater than, say, 1-in-4 chance that I end up making no more money in my baseball career, you don’t have to ask me twice to sign a contract that guarantees me somewhere between $24 and $55 million. I’m popping the champagne that night and paying for all of my friends to join me on a celebratory trip to Vegas. Read the rest of this entry »


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 »


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 »