Fantasy Baseball: Advanced Stats Primer

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Advanced stats in fantasy baseball can be very useful. Unfortunately, most advanced stats have little bearing on fantasy value. WAR, what is it good for? Jack shit homey.


Now there are obviously some advanced stats that can be critical tools in the quest for fantasy glory. We call these stats “Starbometrics.” You see, “Starbometrics” focuses solely on the advanced stats that actually help portend fantasy greatness or failure. There are many inconsequential statistics out there that some people (fantasy “experts” especially) try to cite in an effort to make it seem like they know what the fuck they are talking about. 


So to help break down the only advanced stats that matter, your boy Big Poppa Pockets has decided to drum up a primer that strictly looks at the stuff that matters in fantasy.


Class begins after the jump:


Advanced Stats For Hitters

The Advanced Stat: Contact Percentage

The Abbreviation: Contact%

What’s a Good Contact%: Anything over 82 percent

What’s a Bad Contact%: Anything below 79 percent

Why You Should Use It: Contact% measures the percentage of swings a hitter takes that they actually make contact on. It’s a good “trend” tool, which is to say that it’s useful to see if there is a trend (one way or the other) in a hitter’s Contact% from year-to-year. Increases in Contact% could mean a hitter is displaying better plate discipline and swinging at better pitches to hit. Decreases in Contact% could point to a loss of bat speed or be the result of a hitter changing his approach.


The Advanced Stat: Ground Ball Percentage and Line Drive Percentage

The Abbreviation: GB% and LD%

What’s a Good GB%: Anything around or below 40 percent

What’s a Good LD%: Anything above 19 percent

What’s a Bad GB%: 50 percent or higher

What’s a Bad LD%: 16 percent of below

These stats literally measure the percentage of batted balls a hitter laces or puts on the ground. A high GB% and low LD% can help explain why a hitter has a very low BABIP. Conversely, a high LD% and low GB% are the calling cards of hitters who are performing very well and making consistently good contact, putting balls in play that are tougher to field. It’s worth noting that some speedy players can get by with a high GB% since their wheels allow them to beat out some throws to first.


The Advanced Stat: Isolated Power

The Abbreviation: ISO

Use It Instead Of: Slugging Percentage

What’s a Good ISO: .190-.210

What’s a Great ISO: Anything above .220

What’s a Bad ISO: .140 or below

This stat is calculated by a really super scientific method of… subtracting Slugging Percentage from Batting Average. Sounds basic? Well, this eliminates all the singles a hitter raps, leaving us solely with the extra-bases (which are a better indicator of power, obviously). This is a terrific, accessible statistic that has proven to be incredibly accurate.


The Advanced Stat: Home Run to Fly Ball Ratio

The Abbreviation: HR/FB

Use It Instead Of: HRs and Slugging Percentage

What’s a Good HR/FB: 15-17 percent

What’s a Great HR/FB: 20 percent or above

What’s a Bad HR/FB: Anything below 10 percent

By measuring the percentage of fly balls a hitters has turn into HRs, HR/FB gives us a good idea of how much power a hitter possesses. This stat can be influenced by home ballpark, as players hitting in San Diego are more likely to have a lower HR/FB ratio while a batter in, say, Yankee Stadium will have a better shot at a higher mark. It’s not a perfect stat, but if a player spends a few years with one team, it’s a solid “trend” tool to see if they are sending more (or fewer) fly balls out of the park.


The Advanced Stat: Infield Fly Ball Percentage

The Abbreviation: IFFB%

What’s a Good IFFB%: Anything below nine percent

What’s a Bad IFFB%: Anything above 13 percent

This statistic literally measures the percentage batted balls turn into infield fly balls. We don’t use this stat all that much, but it helps to explain some BABIP issues players may be having. Infield flys are the easiest batted balls for fielders to turn into outs, so if you see a player trending negatively in this area, chances are their batting average is suffering a bit.


The Advanced Stat: Strikeout Percentage and Walk Percentage

The Abbreviation: K% and BB%

Use It Instead Of: Strikeouts and OBP

What’s a Good K%: 16-18 percent

What’s a Good BB%: Anything in double-digits

What’s a Bad K%: Anything above 20 percent

What’s a Bad BB%: Anything below seven percent

These statistics literally tracks the percentages of plate appearances that end with a walk (BB%) or strikeout (K%). They are among the best “trend” tools fantasy owners can use to see if a hitter’s plate patience is improving or eroding. They may not be considered “advanced stats” by all of you, but they are worth mentioning solely because of the value they possess.


The Advanced Stat: Swinging Strike Percentage

The Abbreviation: SwStr%

Use It Instead Of: Strikeouts

What’s a Good SwStr%: Anything below eight percent

What’s a Great SwStr%: Anything below 6.5 percent

What’s a Bad SwStr%: Anything above nine percent

One of my favorites. This statistic is measured by calculating how many swings a hitter takes that result in no contact whatsoever (a swing and miss). Sometimes, hitters have a high K%, but if their SwStr% is trending in a positive direction, it gives us hope that they aren’t completely lost at the plate. Another quality “trend” tool, but it also stands as a great single season measure of success.


The Advanced Stat: Weighted On Base Average

The Abbreviation: wOBA

Use It Instead Of: OPS

What’s a Good wOBA: .350-.370

What’s a Great wOBA: Anything above .380

What’s a Bad wOBA: Anything below .330

The calculation is so complex for wOBA, that I can’t even begin to describe it. What I can tell you is that it takes all key offensive contributions a hitter makes, then spits out a number that is scaled in the same way as OBP. It sounds convoluted, but it’s proven to be more accurate than OPS at measuring a hitter’s overall production. The problem with OPS is that it treats Slugging Percentage and On-Base Percentage as equal by simply adding the two together. However, given the fatal flaw with SLG (a hitter can go 2-for-2 with two singles and have a 1.000 SLG that day), wOBA gives fantasy owners a better alternative. Look at the best hitters every year, and you’ll see they were among the league leaders in wOBA.


Advanced Stats For Pitchers

The Advanced Stat: Contact Percentage

The Abbreviation: Contact%

Use It Instead Of: Batting Average Against

What’s a Good Contact%: 76 percent or below

What’s a Bad Contact%: 82 percent or higher

Contact% measures the percentage of swings an opposing hitter takes that they actually make contact on. It’s a proper “trend” tool that tracks if a pitcher is giving up more or less contact as their career progresses.


The Advanced Stat: Fielding Independent Pitching and Expected Fielding Independent Pitching

The Abbreviation: FIP and xFIP

Use It Instead Of: ERA

What’s a Good FIP/xFIP: Anything below 3.85

What’s a Great FIP/xFIP: Anything below 3.5

What’s a Bad FIP/xFIP: Anything above 4.1

The Sons of Roto aren’t very fond of FIP or xFIP, but they still have some value. The way these two stats are calculated is by taking into account only the things the pitcher can control (walks, strikeouts, HRs). The result is a number that is scaled to look like ERA (a stat that can be very misleading despite it's overwhemling popularity). FIP and xFIP have some use because they remove the luck factor associated with a pitcher’s defense. The difference between FIP and xFIP is that xFIP uses the league average HR/FB for pitchers to put them all on an even playing field. The problem with that is that home parks ABSOLUTELY play a role in a pitcher’s performance, so giving a pitcher in San Diego and a pitcher in Yankee Stadium the same HR/FB makes little sense because if each of those pitchers traded parks, their HR totals would change. These stats are best employed when looking at whether or not a pitcher is experiencing some luck and can help a fantasy owner determine if an ERA correction is coming for a pitcher. However, context needs to be used when incorporating FIP and xFIP.


The Advanced Stat: First Pitch Strike Percentage

The Abbreviation: F-Strike%

What’s a Good F-Strike%: 61 percent or higher

What’s a Bad F-Strike%: Below 58.5 percent

This statistic measures the number of first pitches a hurler throws that result in a strike. It essentially measures how good a pitcher is at getting ahead in the count. It’s a terrific “trend” tool that can help track whether or not a player is getting better at the art of pitching.


The Advanced Stat: Ground Ball Percentage and Line Drive Percentage

The Abbreviation: GB% and LD%

What’s a Good GB%: Anything above 45 percent

What’s a Good LD%: Anything below 18 percent

What’s a Bad GB%: Anything below 40 percent

What’s a Bad LD%: Anything above 20 percent

Just like with hitters, these stats measure the percentage of batted balls that end up as grounders or line drives. Another quality “trend” tool. 


About Starbonell

Starbonell is the co-founder of Sons of Roto and one of the most insightful and colorful fantasy analysts in the game. Mixing intelligent and well-researched advice with an entertaining style of writing that is easy to digest, Starbonell is the king of info-tainment.