Sam Fuld figures it was 2005, his first year in pro ball, when he first read “Moneyball.”

To call it life-changing would be an exaggeration.

But Michael Lewis’ best-seller about Oakland Athletics general manager Billy Beane’s analytical, data-driven approach to building a team appealed to Fuld on multiple levels. Not only was he trying to crack the big leagues as a short, speedy outfielder, but he also was an economics major at Stanford. He loved numbers, especially numbers in baseball.

“Math was my favorite subject in school, so I was interested in that side of the game from a really early age,” Fuld said. “I was always into reading boxscores. I would carry around books, like handmade books, of baseball stats.”

As a player, though, Fuld felt limited in applying sabermetrics. He knew that on-base percentage mattered more than batting average, but as a .227 career hitter (with a .307 OBP), he still had to scrape for a roster spot.

It wasn’t until 2015, Fuld’s last year in the majors, that the numbers really took over. The introduction of Statcast, a high-speed tracking technology, made more data available to every team. Math and science became as much a part of the game as balls and strikes. Teams that were at the forefront of the sabermetric revolution were able to gain a bigger advantage. Teams that weren’t (the Phillies, for instance) needed to catch up -- and in a hurry.

Sam Fuld before a spring training game.
YONG KIM / Staff Photographer
Sam Fuld before a spring training game.

Over the last four years, at the direction of owner John Middleton, the Phillies have made major investments in technology and personnel, building up a research-and-development staff often by hiring people with non-traditional baseball backgrounds. Fuld is in his second season as the team’s player information coordinator. His job: Bridge the chasm between the new-age analytical and old-school scouting realms. He breaks down numbers that are culled by the Phillies’ R&D staff and presents them to coaches and players in ways that can be easily applied.

“It might be a little easier for me to relate to [players],” Fuld said, “and maybe they buy into some information that comes from a guy who had dirt in his spikes. I think there’s that component.”

Like it or not, analytics is here to stay. Here, then, is a primer on a few metrics that don’t appear on any ballpark scoreboard but are worth knowing.

FIP

What it is: Fielding Independent Pitching takes into account only the three “true” outcomes that don’t involve defense -- unintentional walk, strikeout, home run -- and turns them into an earned-run average-like number. It’s a more complex computation than ERA, in part because it involves a variable “constant” that usually approximates to 3.2.

Here’s the formula, which looks like it requires an algebra degree: (HR x 13) + (3 x [BB + HBP]) - (2 x K) / IP + FIP constant.

What it shows: ERA is the traditional metric for gauging pitching performance. But while ERA encompasses every outcome, including balls hit into the field of play, FIP is considered a more accurate indicator because it removes results that a pitcher has limited or no control over. Other stats exist to present a similarly truer picture than ERA, including Skill-Interactive Earned Run Average (SIERA) and Adjusted-ERA, which is ballpark dependent. But FIP has been used for years within the game and was brought more into the mainstream when Zack Greinke won the 2009 AL Cy Young Award and cited it as the metric that valued more than any other to measure his performance.

Nick Pivetta's FIP was better than his ERA last year, which made the Phillies brass feel confident in their starting rotation entering 2019.
CHARLES FOX / Staff Photographer
Nick Pivetta's FIP was better than his ERA last year, which made the Phillies brass feel confident in their starting rotation entering 2019.

How the Phillies use it: In addition to using FIP to judge a pitcher’s real-time effectiveness, the Phillies trust it as an accurate indicator of future performance. Part of the reason they didn’t upgrade their starting rotation in the offseason was that Vince Velasquez, Zach Eflin and Nick Pivetta each had a lower FIP than ERA last year, leading the team to believe that they are each primed for continued improvement. Velasquez, for instance, had a 3.75 FIP compared to a 4.85 ERA, which supports the .322 batting average in balls in play against him (.300 is average).

» READ MORE: Why the Phillies believe starting rotation’s three-week run of success is sustainable

What they’re saying: “I remember it more on the scouting side of things,” said Phillies pitching coach Chris Young, a former minor-league pitcher and later a scout with the Houston Astros. “It was the tool we would use to describe a guy that maybe wasn’t having the best year that you thought was maybe undervalued. It was the way to describe the guy that might be on the market that offseason whose FIP is 2½ points lower than his ERA. That was the first time that I remember being exposed to it.”

wOBA

What it is: Weighted On-Base Average is a version of on-base percentage that accounts for how a player reaches base rather than simply whether he reaches base. The idea, quite simply, is that all hits aren’t created equal. To wit: A home run is almost always more valuable than a single. Like FIP, wOBA involves more complex mathematics and a variable “factor” that weights each type of hit based on league averages each year.

The formula: [(unintentional BB factor x unintentional BB) + (HBP factor x HBP) + (1B factor x 1B) + (2B factor x 2B) + (3B factor x 3B) + (HR factor x HR)] / (AB + unintentional BB + SF + HBP).

Rhys Hoskins' success at the plate this season is obvious. But his wOBA says even more: He's the fourth best slugger in the NL.
CHARLES FOX / Staff Photographer
Rhys Hoskins' success at the plate this season is obvious. But his wOBA says even more: He's the fourth best slugger in the NL.

What it shows: Once upon a time, batting average was the accepted measure of offensive performance. Then, it was superseded by on-base percentage. wOBA takes on-base percentage to the next level. It treats each type of hit as a distinct outcome, weighting each in proportion to its actual run value. Bryce Harper’s high on-base percentage (.374 through Tuesday night) relative to his low batting average (.236) indicated that he had been reaching via the walk even at a time when he wasn’t hitting. But his wOBA (.355) was lower than his on-base percentage, which better reflected his overall struggle.

How the Phillies use it: wOBA is among the publicly available metrics, along with Weighted Runs Created Plus (wRC+), that hitting coach John Mallee trusts the most, so much so that several players last season donned shirts that read, “Chicks Dig the wOBA.” Like FIP, it can be used as both a measure of real-time performance and future success. By every measure, including his .302 batting average and .425 on-base percentage through Tuesday, Rhys Hoskins is having a terrific season. But his wOBA (.439) was fourth-best in the National League, an indication that he has been one of the best hitters in baseball.

What they’re saying: "It’s weighted on-base average. It’s better than slugging,” Mallee said. “A single is better than a walk, a double is better than a single, and so on, and wOBA shows that better than probably any other number. I was fortunate enough being in Houston and Chicago [with the Cubs] to learn a lot of that stuff. We have Sam Fuld with us now, and having him explain to the player the importance of these metrics and what they actually really mean and how you’re evaluated as an offensive player, they can better understand those things. And once they understand, it makes more sense to them. They look at the same numbers that we do.”

Launch Angle

What it is: Launch Angle represents the vertical angle at which the ball leaves a player’s bat at the point of contact. Too low (typically less than 10 degrees) and a hitter is likely to produce a ground ball; too high (usually greater than 50 degrees) and he’s likely to pop up. The angle on a line drive is generally 10 to 25 degrees, a fly ball 25 to 50 degrees. Ted Williams preached the value of launch angle in “The Science of Hitting,” his 1971 book. Many coaches have taught for years that a great hitter must tailor his swing to match the plane of the pitch and send the ball in the air rather than swinging down at the ball. But the launch-angle craze didn’t really take root until a few years ago when several major-league hitters began talking about it after transforming their careers. Josh Donaldson, Justin Turner, J.D. Martinez and Daniel Murphy are a few of the more vocal proponents of launch angle.

The Phillies' study of Launch Angle has paid off particularly well for Maikel Franco.
YONG KIM / Staff Photographer
The Phillies' study of Launch Angle has paid off particularly well for Maikel Franco.

What it shows: The advent of Statcast in 2015 made more players aware of data points such as launch angle and confirmed a law of physics that might have seemed self-evident: Balls hit with a higher launch angle are more likely to result in a hit. Combine the correct launch angle with bat speed and those hits are more likely to wind up over the fence. If that wasn’t already the goal, the increase in defensive shifting has caused more grounders to get gobbled up than ever before. With fewer holes on the infield, hitters are benefiting more than ever from getting the ball in the air. Most hitting coaches believe the ideal launch angle is between 25 and 35 degrees, so over the last few years, many hitters are making a concentrated effort to adjust their swing mechanics accordingly to produce more balls in the air.

How the Phillies use it: The Phillies made a significant investment in HitTrax, technology that offers immediate feedback about launch angle, exit velocity, and projected outcomes, for their batting cages at the major- and minor-league levels. Last year, in looking back at Maikel Franco’s career trends, Mallee concluded that the righty-swinging third baseman was prone to making frequent, hard contact but mostly on the ground and to the left side of the infield. Franco still averaged 24 home runs per season over the last three years. But if he could somehow improve his launch angle -- 11.9 degrees in 2016, 11.4 degrees in 2017, only 9.5 degrees last season -- and get the ball in the air more frequently, Mallee believed those hard-hit groundouts could be extra-base hits. The Phillies worked with Franco on his swing mechanics, and while it has taken time to perfect, his launch angle through last weekend was up to 19.5 percent. It isn’t a coincidence that he ranked second on the team in homers (seven) and slugging percentage (.514).

Phillies hitting coach John Mallee has helped improve his squad's at-the-plate performance.
YONG KIM / Staff file photo
Phillies hitting coach John Mallee has helped improve his squad's at-the-plate performance.

What they’re saying: “They showed me everything -- actual numbers, they showed me video, they showed me my swing, too,” Franco said. “I know there’s a couple balls that I hit on the ground, I should’ve put it in the air. It’s going to be better success. That’s the way that I’m working on it right now. It sounds crazy. But when you get it, when you get it right, you feel like, ‘Oh, that’s the way that I want to work, that’s the way that I want to do my stuff, and that’s the way that I’m going to get better.’”

Spin Rate

What it is: Spin Rate represents the number of revolutions per minute made by a baseball after the pitcher releases it. The amount of spin on a ball changes its trajectory. Research shows that four-seam fastballs and curveballs are tougher to hit when they have higher spin rates. Offspeed pitches, such as change-ups and knuckleballs, are more difficult to hit if they spin less.

Jerad Eickhoff's fastball spin rate is the fastest in the Phillies' starting rotation.
Jeff Roberson / AP
Jerad Eickhoff's fastball spin rate is the fastest in the Phillies' starting rotation.

What it shows: Like some popular sabermetric stats, spin rates can be predictive of future performance. For instance, if a pitcher is achieving a high spin rate on his fastball but not getting particularly good results, it might be reasonable to conclude that he’s likely to turn things around. Among Phillies relievers, David Robertson has the highest fastball spin rate this season (2,580 RPM), while Adam Morgan has the highest sprin rate on breaking pitches (2,868 RPM). Among starters, Jerad Eickhoff has the best fastball spin (2,414 RPM), while Nick Pivetta has the best breaking ball spin (2,740 RPM).

How the Phillies use it: Spin rate is another data point for the coaches and analysts to reference when evaluating the Phillies’ pitchers as well as pitchers in other organizations. But how do the players use it? In most cases, spin rate isn’t anything they think about on the mound. But in the days between starts, it can help explain what happened in a previous start or illustrate something that needs to be fine-tuned in a bullpen session.

Zach Eflin has learned the benefits of Spin Rate: "A higher spin rate on your family is going to make it more deceptive."
JOSE F. MORENO / Staff Photographer
Zach Eflin has learned the benefits of Spin Rate: "A higher spin rate on your family is going to make it more deceptive."

What they say: “For me, personally, it’s all mechanical and making sure I get down that slope,” right-hander Zach Eflin said. “Because if I get down the slope with a good stride, I know I’m going to have a good spin rate on the fastball that day. And a higher spin rate on your fastball is going to make it more deceptive. Really, for me, it’s more worrying about mechanics and consistency throughout a bullpen and in games. There’s a lot of numbers and a lot of ways to calculate pitchers nowadays. The name of the game for however long baseball has been around is just get outs. That’s really kind of the mindset.”

DRS

What it is: Defensive Runs Saved attempts to quantify overall defensive performance by combining errors, range, arm strength and accuracy, double-play ability, and other factors into one number that represents how many runs a player or a team saved relative to the league average. A positive number is considered to be above average; a negative number below average. DRS uses publicly accessible data compiled since 2003 by Baseball Info Solutions, a Lehigh Valley-based company, to chart where each ball is hit. The player essentially is graded on degree of difficulty. According to Statcast, if an outfielder makes a play that the data indicates gets made 60 percent of the time on average, he receives 0.4 points; if he doesn’t make the play, he loses 0.6 points. The player’s overall score is adjusted to the league average, and then that score gets adjusted for how many runs the adjusted score is worth.

Bryce Harper and the Phillies use Defensive Runs Saved more than fielding percentage to judge how they're performing.
ELIZABETH ROBERTSON / Staff Photographer
Bryce Harper and the Phillies use Defensive Runs Saved more than fielding percentage to judge how they're performing.

What it shows: Just as FIP improved upon ERA and on-base percentage (and later wOBA) enhanced batting average, DRS is regarded as having furthered fielding percentage, a more traditional defensive metric, because it accounts for range. But unlike pitching and hitting metrics, there are inherent problems with DRS and other similar defensive statistics, including the popular ultimate zone rating (UZR). Issues arise mostly because of the imprecision with measuring where every ball is hit. In addition, DRS doesn’t figure in shifts, and the preponderance of infield and outfield shifts over the last few years has made it a less reliable metric.

How the Phillies use it: The last year has taught them to be less trusting of DRS and other public-facing metrics. Sample size is always important, but with defensive metrics in particular, the larger the sample, the better. Generally speaking, the Phillies believe that defensive data must be culled over a two- or three-year period to have the best chance for accuracy. The Phillies pay attention to DRS, which ranked them as the worst defensive team (minus-146) in baseball last year, but they mostly use it as a reference. Like most teams, they compile their own data and put their research-and-development staff to work on developing in-house metrics that they trust more than the publicly available information.

What they say: “We got exposed to some of the potential shortcomings of some public-facing metrics related to defense last year,” Fuld said. “We learned a little bit more about DRS. We reached out to [Baseball Info Solutions] directly and got some more information about what’s behind their model. We learned quite a bit, and I think what we learned is that what we have internally is a little more reliable. What we have internally, we know what goes into it and it makes sense from a mathematical standpoint. We feel it takes things into account much more in-depth and much more accurately than some public metrics do.

“The problem with defensive metrics is it still takes a pretty big sample to really believe in it. There’s really not a whole lot of balls in play that go to each and every position individually, so they can be misleading in small samples. You have to look over the course of two, three, even four years to get an accurate picture of how a guy is defensively.”

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