Power Production (Batter GB/FB Ratio)

 

Good morning everybody.  Today we are going to revisit some research that we've done on batter Groundball/Flyball (GB/FB) ratios.  Stated simply, hitters with lower GB/FB ratios hit more home runs and have a higher slugging percentage than hitters with high GB/FB ratios (in general, of course there are always exceptions).  The logic here is easy to follow.  Balls hit in the air have a chance of leaving the park for a homer, and are also more likely to result in a double.  Balls hit on the ground have NO chance to leave the park (rare inside-the-park homers notwithstanding), and are less likely to go for extra bases.

 

Our goal today is to reference our prior research, and to see if there are any batters who are outliers.  We can look at this in two ways.  First, we will look for hitters with low GB/FB ratios but sub-par power production.  Many of these hitters can be expected to improve their level of power output.  Secondly, we will look at hitters that have high GB/FB ratios and a high level of power production.  In many cases we should expect a power drop-off from these batters.

 

In terms of reference material, I strongly suggest you look up the full article on GB/FB that was based on five season's worth of historical statistics.  Key data from that study is below.  Hopefully this makes the relationship between GB/FB ratio and both HRs and SLG pretty clear.

 

 

 

 

The first thing I did was to compile the GB/FB stats for all qualified batters so far this season (qualified batters must have at least 3.1 plate appearances for each game their team has played).  Data is through games of 06/04.  (GB/FB ratios can be found on ESPN.com's stats pages under the 'Sabermetric' category, as well as on their individual player stat pages under 'Miscellaneous Batting'.)

 

The first population of players I examined was those who had GB/FB ratios lower than 1.00.  Based on the chart above, these players can be expected to have a slugging percentage around .490 or greater.  This group included 44 players, which is too many to represent here, but I picked the ones from the list who we would consider moderate to strong power hitters who have not produced to expectations so far this season.  Data for these players is below.

 

 

I know you probably don't need me to tell you this, but Frank Thomas (you know...he of the career .562 SLG in 2000+ games) ain't gonna be slugging below .400 for long.  His flyball rate isn't as low as it was the last two seasons, but is still as low as it was in 2004, when he had an excellent 13.3 AB/HR rate (which then in turn equates to 45 HRs over a 600 AB season).  Bottom line, BUY Frank Thomas.  As much as it IRKS me to have to say it...pretty much the same recommendation goes for Pat Burrell.  I say it irks me because I have to watch the guy play constantly, and to us he looks lost at the plate too much of the time.  But...all his indicators are good.  Some of them are really good, in fact.  Despite the .222 AVG and .388 SLG, his GB/FB ratio of 0.58 is the lowest mark of his career.  Both his 20% walk rate and 1.08 EYE (which Paul mentioned yesterday) are the best of his career as well.  Buy Pat Burrell too if you need power.  Garrett Atkins, Vernon Wells, Jermaine Dye, Paul Konerko, and Scott Rolen are others that should be considered good bets to turn their lack of power production around.  (Interesting to note that all these players were also rated a "Buy"in the latest Strategy Plus Recommendations for Hitters.)

 

Next we will look at the players who have some power production this year, but also have high GB/FB ratios, suggesting that the power may not be sustainable.  These players have GB/FB ratios greater than 1.50, and also have SLG greater than .420.

 

 

 

I'm not gonna harp on Derek Jeter, Ichiro, or Carl Crawford here because they sort of break the mold.  This is especially true of Jeter and Ichiro who have both managed to maintain .400+ SLG despite 2.00+ GB/FB ratios.  These guys also hit a lot of doubles and triples. (Incidentally, Jeter and Ichiro both have exactly 52 career triples.  Weird.)  Lyle Overbay had been hitting a larger percentage of ground balls this year, but that won't matter for a while as he's on the shelf.  I feel fairly confidant saying that Casey Kotchman's .497 SLG so far is due for a correction if he maintains this high a GB/FB ratio.  Travis Hafner is has seen a huge increase in his GB/FB ratio this season (1.65 so far versus 1.05 career).  I would expect this to change over the coming months, and his power production will get even better.  Orlando Hudson's GB/FB ratio is right in line with his mark from last year, when he slugged .454, so it is reasonable to expect that his .467 SLG this season is legit.