Posted: 2019-04-23 12:18:55 (ET) [ 534 views ]
In my last blog article, I introduced the concept of ADI (the air density a game is played within) and the VMI (the Visual Memory of a hitter in MLB). In Major League Baseball the ADI is affected by the altitude air pressure, the temperature and the humidity at game time. All three of these ingredients in air fluctuate during the day but remain reasonably stable during the contest.
Utilizing the “Neeley Scale” which is primarily earth surface air density, all of MLB plays between approximately 40 at the light end of the scale in Colorado and 80 in the heavier air at sea level.
If the air is heavy the pitches will be more reactive in terms of movement as they speed toward the strike zone. We call the heavy air venue’s and the colder gamedays at sea level “Heavyweights.” Colorado is a “Featherweight” in terms of air density, but on cold days can jump into the “Lightweight” categories of Atlanta, Texas and Kansas City on those teams' hottest days. The Central Division tends to bounce from the “Heavyweights” in April to the “Welterweights” and finally to the “Middleweights” in the heat of the summer. These various weights of air regardless of whether it is caused by altitude, temperature or humidity allow the pitcher more or less movement by up to 4 inches on the four-seam fastball in MLB ballparks.
If a hitter has been hitting in a Heavyweight air for a series, his elbows must be positioned higher (in his initial stance and pre-swing) to be prepared for the 4 inch extra lift on the four-seam fastball, than in Lightweight air. So, the lesser lifting, but further sliding two-seamer will then, be a good groundball producing pitch for the pitcher to use.
Conversely if a hitter has been in Colorado for an entire series and played all three games, hit the ball relatively well, then his elbows have relaxed downward by a few inches to prepare to swing at the lesser lifting four-seamer. So, if the ensuing pitcher relies on the two-seamer, then the hitter’s stance and pre-swing will put his bat squarely on the two-seamer in Welterweight air even if it slides more so and he hits it off the handle or the end of his bat. But generally, it is a pitch that should be used sparingly and cautiously against such a team.
These two examples identify the extremes of the VMI. In the first example the VMI would calculate to a high Plus VMI because when he leaves sea level to go to, say Atlanta, his pre-swing stance would put his bat above the center of the ball. In the second example the VMI would calculate to a high Minus VMI because when he leaves Colorado to go to a place such as Arizona his pre-swing stance would put his bat below the center of the ball at the zone. In this case, the Minus VMI would identify a hitter (actually the entire team) as potentially dangerous against downward breaking pitches, but anemic against the 4-seamer.
|2020-02-13||Welcome to Spring Training - 2020|
|2019-12-04||Re-Posted: ADI--VMI Outlook for 2020|
|2019-11-02||ADI--VMI Outlook for 2020|
|2019-10-31||Washington Nationals World Champs|
|2019-10-05||MLB Winding Down - - NBA Gearing Up|
|2019-09-15||Higher VMI's pattern contrasted with Lower VMI's...|
|2019-08-14||I'm Breaking My Promise|
|2019-08-02||VMI Production in the Smallest of Ranges|
|2019-07-30||August and September are Absolutely Weird in MLB...|
|2019-07-27||Mental Issues Lead to Analysis by VMI - and Intr...|
|2019-07-12||Pitcher-Type Rating on Detailed Match-ups|
|2019-07-08||How Will a Dome in Arlington Change Competition ...|
|2019-06-22||Pitcher-Type Rating on Detailed Match-ups|
|2019-05-31||The Mental Side of Hitting That VMI Isolates|
|2019-05-16||Follow-Up 3 to BaseballVMI - Intro|
|2019-05-07||Follow-Up 2 Introduction to Baseball VMI|
|2019-04-23||Follow-Up Intro to BaseballVMI|
|2019-03-28||Where Did VMI Come From?|
|2019-03-27||Team VMIs and ADIs for Opening Day|
|2019-03-24||Tracking the Teams VMI|
|2019-03-13||Which is more important eye imagination, or hand...|
|2019-03-02||More Ideas For Data Mining ADI/VMI|
|2019-02-07||Wanting to see all our website features and data...|
|2019-01-23||Retractable Roof in Arlington Park - 2020|
|2018-11-25||BasketballVMI.com Taking Center Stage|
|2018-11-03||BasketballVMI.com is now live|
|2018-10-29||Congrats to the Boston Red Sox - World Champions...|
|2018-10-25||Things are about to change to a Slugg-fest in LA|
|2018-10-07||Coming Soon from VMI: NBA BASKETBALL VMI|
|2018-10-03||How'd They Win; Why'd They Lose: COL vs CHC|
|2018-10-02||Colorado Rockies at Los Angeles Dodgers, Yesterd...|
|2018-09-29||Big Weekend in the West - - Colorado and The Dod...|
|2018-09-24||How'd They Win; Why'd They Lose - BAL vs NYY|
|2018-09-19||How'd They Win; Why'd They Lose - LAA vs OAK|
|2018-09-15||Fourth Game - Against the LA Dodgers......|
|2018-08-28||Mark Schlereth Commented on Rockies Young Pitche...|
|2018-08-17||How did San Diego get here?|
|2018-07-31||How'd They Win; Why'd They Lose - TOR vs OAK|
|2018-07-28||How'd They Win; Why'd They Lose - TEX vs HOU|