Emilio Bonifacio is one of three Miami Marlins who have the speed to be aggressive on the bases. But just how much are these stolen bases worth? Mandatory Credit: Howard Smith-US PRESSWIRE
The season is still young, but it is very clear that the Miami Marlins are determined to make baserunning, and particularly basestealing, a major part of their new offense. With the traditionally aggressive Ozzie Guillen as Marlins manager, one would expect that brand of baseball.
"That's what the ideal is," said Guillen, now in his first year as the Marlins' manager. "The hitters are going to see a lot of fastballs. And the catchers have to be aware, the [opposing] coaches have to be aware. It's just nice when you can run a little bit. That makes everybody a little heads up."
This early aggressiveness and the above quote show that Ozzie Guillen wants a lineup very similar to the one he saw in 2003 when he was a third base coach with the Marlins. The much-romanticized pairing of Juan Pierre and Luis Castillo gets a lot of attention when it comes to reminiscing about the days of speed gone by. In Jose Reyes, Emilio Bonifacio, and to a slightly lesser extent Hanley Ramirez, the new Miami Marlins think they have the next best speedster pairing that will help take them to a World Series.
But there is a danger in running the bases, and the Marlins have to find the right balance between aggressive baserunning and stupid baserunning.Primer: The Value of a Stolen Base
Before we go into what that balance may be, it is important to point out what the value of a stolen base actually is. In the offseason, we talked about using linear weights as measures of how many runs a play is worth. Here is an example of the runs above average values for each event listed in that article:
Event Runs Above Average Non-intentional BB 0.33 Hit-by-pitch 0.39 Single 0.47 Double 0.76 Triple 1.06 Home Run 1.41 Stolen Base 0.20 Caught Stealing -0.46 Strikeout -0.31 Other Outs -0.30
I highlighted in bold the corresponding values of the stolen base and caught stealing. In this current, lower-scoring environment, it is likely that the stolen base is worth a little more, while the caught stealing is worth a very similar amount. Either way, the general point is obvious: a stolen base is worth a lot less than a caught stealing. And this makes a lot of sense when you consider that a caught stealing combines the loss of a runner and an out, whereas a stolen base only advances one base. Inherently, it should be clear that, despite the effects being binary (either you get a stolen base or you are caught stealing), advancing a base is not worth nearly as much as taking a base and an out away from your team.
In fact, a caught stealing is worth more than twice as much as a stolen base in a negative sense. By looking at the ratio between stolen bases and caught stealing in terms of run value, we can actually calculate at what rate a player needs to steal successfully in order to "break even" on stolen base attempts. Using the above run values, one finds that a runner needs to be successful 70 percent of the time to break even with being caught stealing. In lower run environments, advancing a base becomes more useful because teams expect to get fewer hits to drive runners in, so the stolen base value increases more relative to the caught stealing value, but not by much. In the end, the breakeven percentage never gets lower than 67 percent and stays close to 70 percent.
Stealing Too Much?
Is there such a thing as running too much if you are watching the Marlins? Let's look back at that 2003 team as an example using our newfound information on breakeven points for basestealing. Juan Pierre stole a league-best 65 bases in 2003, but he also was caught 20 times. That means that he was successful at a 76 percent rate, and such a success rate meant that he garnered almost four runs above average on stealing bases based on the above linear weights values. Luis Castillo, on the other hand, was not as lucky, as he was caught 19 times and only stole 21 bases, a 53 percent success rate. That meant that he was worth almost five runs below average for the Fish that season on basestealing.
Could the Marlins run into similar issues in 2012? On the one hand, the players involved have a strong skillset for stealing bases, but on the other hand, if Guillen sends them too often, they will waste that skillset by going at unhealthy and disadvantageous times. If the players stick to their usual rates of steal attempts, they may be able to find the same success they have always had, and the Marlins could reap the benefits by simply having more basestealers.
Below are the stolen base attempt rates (SBA%) for each of the three Marlins running threats since 2009.
Each of those three have reasonable stolen base attempt rates for speedsters of their caliber. Over the years, Reyes has declined in terms of his aggressiveness on the bases, while Bonifacio has only grown more confident (as well he should be). But tinkering with their career rates or their expected ideal rates too much may tilt them from a delicate balance between ideal play and inefficient play. For example, Reyes may have declined in stolen base rate from his glory years of 60 to 70 stolen bases a season because of his injuries and subsequent loss of speed. If Guillen is too aggressive, it may push Reyes past his ideal mark and into less ideal territories. Ramirez could also be a player who, due to change in his physique over the years, should run less than he did in the past, but may be pressured to be more aggressive by Guillen.
Each of these guys are likely going to be successful enough to steal appropriately, as each of their career success rates are significantly above the cutoff of around 70 percent. It is too early in the season to determine how much the team is gaining or losing by being aggressive (though later today, we will look at the run impact of certain baserunning plays so far this season), so such an analysis of what has occurred in 2012 would be useless. So my suggestion would be for Guillen to allow their natural baseball instincts to govern their work on the bases. In particular, I would allow Ramirez and Reyes to determine when or when not to steal on their own accord, meaning that Guillen should step back and not "put on plays" that may lead to inefficient baserunning. Bonifacio, on the other hand, is the perfect candidate for those types of plays, if Guillen must run them. Bonifacio is the fastest of the three players and is the most likely to make something out of a busted baserunning play, so Guillen can be more aggressive with him. Still. this is an issue to keep an eye on, and you can bet Fish Stripes will be on the case if we see any ugly baserunning plays made by the triumvirate and their mad captain.