This week, MLB.com is The other two forces change the direction of the ball, resulting in movement. Win Probability & Box Scores
Website admin will know that you reported it. In fact, if you look at my spreadsheet template, you will see it there. Here's Rendon on Aug. 9, after his first 12 games, vs. Rendon today,...When Padres phenom Fernando Tatis Jr. mashed a grand slam on a 3-0 pitch in a game against the Rangers on Monday night -- extending his team’s seven-run lead in the eighth inning -- it set off baseball’s latest debate over the unwritten rules.
Suffice it to say it has to do with the fact that the Magnus acceleration is not constant but proportional to the square of velocity. In other words, if a pitcher actually threw his curveball with 100 percent spin efficiency, the inferred spin efficiency using Technique 1 would only by about 75 percent. Or, said differently, it is a physics/analysis issue, not a measurement issue.Now let’s return to the discussion of spin efficiency, referring to Figure 3, which is a box plot of the ratio of inferred spin to exact spin (essentially, the inferred spin efficiency) for each pitch type for each of the two techniques. But there is experimental noise in the trajectory, which results in some significant noise in the inferred transverse spin and therefore in the inferred spin efficiency. But the way Wisler went about his two innings of work was something modern baseball has rarely seen.
Later.Excellent work, as always. And please don't worry, your report will be anonymous.You can flag a comment by clicking its flag icon. In the past few years, the concept of “spin efficiency” seems to have taken hold. After a...Baseball is a game filled with history, numbers and records, to the extent that some milestone moments are met with a shrug or a quick smile before everyone moves on. Then, last August, he was released for the second...The beauty of Fernando Tatis Jr. and Juan Soto taking over the game of baseball is that two 21-year-old phenoms can both be so amazing as different types of superstars. Recall that the actual spin efficiency is exactly 1.0 (i.e., 100 percent) for every pitch in the simulation, so any deviation from 1.0 on the plot represents an error.While Technique 2 gets within about one percent of one for nearly every pitch, Technique 1 does much worse, especially for curveballs (CU), for which the transverse spin is consistently underestimated by about 25 percent due to the incorrect gravity correction discussed earlier. Admins may or may not choose to remove the comment or block the author. And please don't worry, your report will be anonymous. As we shall see, the latter produces more accurate results than the former.The first step in the analysis was to simulate a set of 2110 “typical” pitches using data downloaded from Using these parameters, the equations of motion were solved numerically using standard techniques to find the trajectory of the pitch from release to home plate in 0.01-sec intervals. Luckily we get...Remember when Anthony Rendon was having the worst start of his life? This represents the trajectory Trackman measures. And please don't worry, your report will be anonymous.You can flag a comment by clicking its flag icon.
Admins may or may not choose to remove the comment or block the author. )“Why is spin interesting, if you already know movement?” From an observer or fan’s point of view, it is not interesting at all. I first wrote about this subject in the article “The Trackman radar system, which is an integral part of the Statcast system installed in every major league park, measures the full trajectory of the pitched ball, from which the movement can be determined and the transverse spin inferred. -You fit the simulated trajectories with both methods, and then recalculated moment metrics for each method. And please don't worry, your report will be anonymous.You can flag a comment by clicking its flag icon. One of these techniques is the one actually used by Trackman; the other is an alternate. Ratio of inferred spin to exact spin for each pitch type derived via the Technique 1 (top) and Technique 2 (bottom) approximation.Great work as usual. Unfortunately as Dr. Nathan will likely point out, the only mechanism for this would be if more or less spin in certain directions affected the drag coefficient substantially. Website admin will know that you reported it. Now, if the “everything else” is due to the Magnus force (i.e., to transverse spin), then the movement can be interpreted as due to spin. And please don't worry, your report will be anonymous.You can flag a comment by clicking its flag icon. DFS Projections
Take a pitch to its logical extremes: Does a pitch at 90 MPH that spins at 2750 RPM and has 7 inches of lateral break and 0 inches of vertical break (per short-form PFX movement) have the exact same effect on the batter regarding deception/intimidation/other factors unknowable as a pitch that is 90 MPH that spins at 7500 RPM and has 7 inches of lateral break and**Attempting to edit for format Dr. Nathan, thanks for writing this. But if you average over a large enough number of pitches, then the inferred spin efficiency is aExcellent article, as always, Dr. Nathan. I will call these MSo now we have two approximate methods of determining the movements from the 9P fit, both of which can be compared to the exact movements. Admins may or may not choose to remove the comment or block the author. Website admin will know that you reported it.
His first pitch to...The Blue Jays are stacked with slugging stars of tomorrow, but is it time to think of Teoscar Hernández as a centerpiece of that long-term future? Admins may or may not choose to remove the comment or block the author.