Charlie Metro: "The great catches are made at the start, not at the end. The end is the net result of the start . . . If you pivot [correctly], you've made one step and you're three or five feet, whatever, toward the ball. . . . But if you do this [leaning the wrong way, stepping across] you've taken three steps and haven't moved out of your tracks. So the great catches in the outfield are made with the initial move."
There is a very important Biomechanical Principle that pertains to the initiation of the baseball swing. The principle states: "A ballistic motion, once initiated, produces trajectories that can only be changed at its margins." This means, the forces applied to the bat during initiation produce trajectories that will set the tone for the entire swing. If the swing is not initiated correctly - little can be done to compensate for it.
The conclusion of the GIIB article shows that team gOBP has a correlation coefficient of 0.95 with R/G, a slight but meaningful improvement over the correlation coefficient of 0.93 between team OBP and R/G. This first test is straightforward: using Retrosheet, I collected team R/G, OBP, and gOBP for all 1,482 team seasons dating back to 1955. I then fit a linear model to these data and computed the correlation coefficients for each pairing. The results are below.

## "On base, on base, everybody talks about on base percentage. Jim Leyland, I like the guys that knock em in. I know, there’s a lot to be said for that. They talk about 'Moneyball' and working the pitcher and on-base percentage. Yes, there’s a lot to be said for that. But my theory is, during the course of a major league game, normally for both teams, there’s enough guys on base. The guys to me, that make the money are the guys that can score them from first and knock em in. I like the slugging percentage, over the on base percentage, myself. That’s just an opinion."

To test this, I collected all batters in the Retrosheet database since 1975 who logged at least 300 plate appearances in two consecutive seasons. (Multiple batters, of course, could appear multiple times.) This covered 5,607 batters, from Barry Bonds's 2002 (.582 OBP, .587 gOBP) to Mario Mendoza's 1979 (.216 OBP, .219 gOBP). As before, I fit a linear relationship between each statistic in year 1 and the same statistic in year 2, and determined the respective correlation coefficients.
Lanky build and weak muscles are not going to cut it if you dream of hitting home runs in a baseball game. You need to build your upper body and muscles, so the most basic thing to do is regularly bring these muscles into action, exercise and toughen them up. Try to do such exercises on a daily basis which involve your entire upper body. This will give you the requisite strength to hit a baseball farther.
```Follow through. Properly following through is important for multiple reasons. Not only will it help you to add all-important distance generating backspin to the ball, but it will help point out any flaws in your swing.[7] In most cases, you want your hands to finish high which ensures that the bat head stays through the hitting zone as long as possible.
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To compare the performance of OBP and gOBP, we compute a weighted mean squared error (WMSE) to quantify the difference between the expected and actual statistic for the set of batter/pitcher matchups in each bin. The number of plate appearances is used to weight each bin, so that more common pairings affected the final score more than rarer ones. We collected all matchups between batters and pitchers with at least 50 total PAs in a season from 2010 through 2013, a sample of more than 750,000 PAs. The WMSE (along with the unweighted mean squared error) for both OBP and gOBP are given below.
Josh Donaldson hit .255 and scored 93 runs; think some of those 76 walks helped him out?  Brandon Moss was the man to own in the first half even with a .268 BA, but was dropped like a rock in the second half where he hit .173.  His OBP slipped from .349 down to .310, but at least he was still playable thanks in part to 14.8% walk rate.  Adam Dun hit .219 in 2013 and while he hit 34, owners cursed him.  Forget the 76 walks and .320 OBP though, it doesn’t count in fantasy.  In 2012 Dunn hit 41 home runs and scored 87 times, but a .204 batting average had him on America’s most hated list.  Using OBP you could have had .333 thanks in part to his 105 walks which batting average didn’t take into consideration.  Dunn’s value in 2012 using OBP was slightly above Adam Jones and his 34 walks.  Dunn had 71 more walks and Jones had 76 more hits, similar results but Jones is rewarded for being on base an equal amount of times.
Of course there’s some difficulty in identifying the best active hitting pitchers, foremost because hurlers are so often asked to just lay down a bunt or attempt to move a runner via sacrifice. And those are good skills to have. So we decided to use OPS (on base % + slugging %) as a measure because sacrifices are filtered out from at-bats and OPS indicates pitchers that can hit and hit for extra bases, and also draw a walk. Now take a look at this group of pitchers’ hitting credentials (minimum 40 at-bats). Also note that the MLB average OPS across all hitters in '16 was .739.
Slugging percentage (SLG): Compared to most of the other "old" statistics, slugging is beautiful in its simplicity -- it's simply total bases divided by at-bats, and gives us a nice snapshot of a player's power. Think about it, with batting average you have to factor in fielder's choices, errors and walks and the such, while slugging is easy (although, it is a derivative of batting average, as you need at-bats instead of plate appearances). It also passes my test for a useful stat -- immediate understanding of what it means when you glance at the number. - Rosecrans
Phase 1 of the swing is by far and away the most important phase. It is at this point where the hitter will either be all they can be or something less than that.  Not to say you can’t still get a “hit” but as we say all the time, “your worst mistake is your first mistake”. This basically means, when you make mistakes early in the swing(phase 1), 100 percent swing efficiency can not be reached.  Here is where early in the swing resides and where  the effortless swing can be achieved. In Phase 1, there are two main objectives.
[box]About the source, Pro Scout Jim Thrift.  Jim’s 28 year career in baseball includes 4 years scouting for the Baltimore Orioles in the amateur, pro and international divisions, 15 years with the Cincinatti Reds as a Major League scout, amateur scout and National Cross Checker, triple A hitting coach, and a long list of other impressive experience in professional baseball. [/box]
A Strong Core is essential to a softball player. So why do so many players have a weak abdominals? Good question. This is another exercise routine that can get lost in translation.  You’re not training your core to look good in your bathing suit, you’re training your core to be functional; to rotate when you swing, open up and rotate when you throw, stabilize your hips and create balance.  Your goal is to mimic your core work in a fashion that transforms power onto the field. Here is a favorite exercise of mine to create rotational core power; rotational medicine ball throws. Start in your hitting stance and hold onto a medicine ball then rotate into a swing. Sounds pretty simple but super effective. My second favorite is bear crawls with bands. The key to this exercise is doing it correctly. Your butt should not be up in the air, back stays flat and your feet should move forward outside of your hips. This is a definite twofer. This exercise hits the hips and core in one movement.
The conclusion of the GIIB article shows that team gOBP has a correlation coefficient of 0.95 with R/G, a slight but meaningful improvement over the correlation coefficient of 0.93 between team OBP and R/G. This first test is straightforward: using Retrosheet, I collected team R/G, OBP, and gOBP for all 1,482 team seasons dating back to 1955. I then fit a linear model to these data and computed the correlation coefficients for each pairing. The results are below.
On-Base Percentage (OBP) measures the most important thing a batter can do at the plate: not make an out. Since a team only gets 27 outs per game, making outs at a high rate isn’t a good thing — that is, if a team wants to win. Players with high on-base percentages avoid making outs and reach base at a high rate, prolonging games and giving their team more opportunities to score.

Getting on base is an important skill, so you want to use OBP to determine if the player in question is a good offensive performer. However, OBP can only take you so far and it should only be used in the context of other statistics because OBP weights every time you reach base equally, whether you hit a home run or an infield single. If used in conjunction with slugging percentage or isolated slugging percentage, OBP is a very useful tool. In general, something like wOBA or wRC+ will tell a more accurate story, but if you’re looking for something extremely simple OBP is a much better bet than batting average.
We all know that a .260 batting average is about average while a mark of .200 is quite poor. We know that .300 is a good figure and that .340 will often win the batting title. However, the values of an average, good, or bad OBP are not so ingrained in us. In 2013, the major league OBP was .318. Among players who qualified for the batting title, Detroit's Miguel Cabrera had the highest OBP with a mark of .442. Kansas City's Alcides Escobar posted the lowest figure at .259. Below, I have included a table that shows OBP for various percentiles in 2013. For example, Matt Holliday's OBP of .389 was better than that of 90% of qualified batters in 2013.
Charlie Metro: "The great catches are made at the start, not at the end. The end is the net result of the start . . . If you pivot [correctly], you've made one step and you're three or five feet, whatever, toward the ball. . . . But if you do this [leaning the wrong way, stepping across] you've taken three steps and haven't moved out of your tracks. So the great catches in the outfield are made with the initial move."
So now going back to the original example of Mike Trout’s 2014 slash line (.287/.377/.561), you should be able to look at it and know not only what statistic each number represents, but what it means in regards to Trout’s value as a player. Before we move on to the next section, however, I also want to mention two stats that are commonly associated (and sometimes included) with the slash line, the first of which is OPS.
Keep your hands in. Whether you are dealing with an inside swing or an outside swing, it is important to keep your hands close to your body. Most of your swing is generated in your hands and wrists. If your hands are extended your bat speed will slow and your power will drop. The palm of your dominant (top) hand should remain facing upwards through contact in order to drive through the ball.
In Part 1, we'll take a look at the method to the madness of on base percentage (OBP) and slugging percentage (SLG) and see if we can give them their due respect on the scale of importance. In part 2, we'll explore why wOBA is a better stat to use than OPS and produce a scale so we can easily see what wOBA is above or below average and how the Tigers' players fit in.
The main application of slugging percentage is to go beyond just being able to tell how good a player is at getting hits, but how good they are at getting quality hits. For example, Robinson Cano and Andrew McCutchen both had a batting average of .314 last year; however Cano slugged just .454 opposed to McCutchen who finished with a .542 mark. While both players got hits just as often, McCutchen got the more valuable kinds of hits more often (he had more doubles, triples, and homers than Cano), so he was the better hitter in 2014.
You can make similar cases for mid-range average guys like Ben Zobrist and Jason Heyward who had averages in the .270 but on base percentages in the .350’s because they could draw walks.  I know, you could just add walks as a category but in doing so you would be penalizing players like Jones along with some of the players from the BA leaders above like Lorenzo Cain, Ben Revere and Josh Harrison.  Now you’re still gonna have those high empty OBP guys just like you would empty BA guys; nothing you can do about that, no system is perfect.  The difference is the right players are being rewarded.  If your hits and walks are equal you are getting on base at an equal clip, right?  Getting on base helps your team, just ask Billy Beane.

Carter came to the Astros from Oakland as a player with a reputation for excellent power, but a scary tendency to swing and miss. In his first full season in the majors last year he did nothing to shake that reputation. Carter hit 29 home runs in 2013, but also struck out 212 times coming with in striking distance of Mark Reynolds single-season record of 223. In the last two years (among hitters with at least 800 PA) Chris Carter has been at the top of the leaderboards in all of the statistics related to failing to make contact with baseballs. The following chart shows his numbers in K%, Contact% and Swinging Strike % and where he ranks among the 190 batters with 800+ PA over the last two seasons: