Home Run Milestones – Who Might Reach Them?
Who has the best shot at breaking Barry Bonds’ record of 762 home runs? Who is likely to reach 500 or 600? We all know the usual suspects, but is there a way to estimate their actual probabilities? Using past performances beyond a given age level, we can try to quantify what we think we already know.
Using baseball-reference.com, it is easy to determine how many home runs every player in the history of baseball has hit starting at any given age. Then for any current active player, we can compare that information with how many home runs they need to reach a certain milestone to find how many players in the past have done what that player needs to do. For example, we find that 36 players have hit at least 64 HR from age 36 on, which is what Vlad Guerrero must do to reach 500 HR.
But to get a probability, we need both a numerator and a denominator. The latter is trickier. We need to identify players at that age who are in some way representative of the current player. We don’t want to take all players at that age, since that would include players who were not at all similar, such as light-hitting middle-infielders, etc. As a first stab at this, I determined (once again using baseball-reference.com) how many players at a given age had hit 20 or more HR. This then represents the approximate pool of power hitters at a given age.
The following table lists players with their age in 2011 (using the baseball-reference criterion, which is their age on June 30, 2011), the number of HR they currently have, the total number of players of the same age who hit at least 20 HR the previous year, and the number of players who have hit enough HR from that age on that would allow the current player to reach the 600 and 500 HR milestones. The last two columns then give the approximate probability using the previous columns. (The NA, obviously, indicates that a milestone has already been reached.)
|Age||Player||HR||# >= 20HR||#(600)||#(500)||%(600)||%(500)|
As an example, we see that for Jim Thome, 25 people have hit at least 20 HR in their age 39 year, and 21 people have hit at least 11 home runs from age 40 on (the amount needed by Thome to reach 600), giving an estimated probability of 84% that Thome will reach 600.While this may seem a little low given how close he is, players often do hit a wall at age 40. A similar calculation for Manny Ramirez gives a 24% chance of reaching 600.
The only other player with a probability of reaching 600 that is even close to these is Albert Pujols, at 19%. He needs 192 more HR and is only 31 this year, but at his current pace it will still take at least 5 years, and a lot can happen in that time. As the number of players who have hit at least 20 HR at a given age shows, HR productivity drops markedly after age 30, with only half as many hitting 20 HR at age 35 as compared to age 30. Adam Dunn is next with an 8% probability of reaching 600 HR.
By the way, for the players who have just one player in the #(600) column (i.e., only one player in the past who performed at a level that would allow the current player to reach 600 HR), that player is always Barry Bonds. So now that steroids have been mostly removed from baseball, you might want to consider it a zero.
For the 500 HR milestone, Pujols leads the way at 78%, followed by Andruw Jones (41%), Vlad Guerrero (33%), Dunn (32%), Miguel Cabrera (19%), Prince Fielder (14%) and Mark Teixeira (12%). While some of these may appear to be a little off – Jones’ probability in particular might seem too high, given his recent decline – they mostly seem plausible.
So – to me at least — the 20 HR level used to determine the pool of similar players gives results that aren’t too far off, on average. If you think the probabilities are consistently too high or too low, you might want to choose a different criterion to choose the pool of similar players. For example, if you use 25 HR, the pools at each age are only about 60% as big, which multiplies the probabilities by a factor of about 1.6. This would make some of the probabilities greater than 100%. If you use 15 HR, the pools rise by 60%, which multiplies the probabilities by about 0.6. This makes the probabilities seem too low to me, which is why I like using the 20 HR criterion. You could also have a different criterion at different age levels, but that introduces even more variables to choose.
What about the ultimate milestone of 763 HR, one more than Barry Bonds? The following table lists the players who can point to at least one past player who performed well enough from their current age to enable the current player to reach the magic 763 number.
|Age||Player||HR||# >= 20HR||#(763)||%(763)|
This list of possible record breakers is very short, and once again, the ones with only one player in the #(763) column (Dunn and Fielder) must duplicate Barry Bonds’ performance to do it. Cabrera adds Babe Ruth to his list of “role models,” while Pujols adds Ruth, Hank Aaron and Raphael Palmeiro. Of course Bonds and Palmeiro used steroids, and Ruth was, well, Babe Ruth (who, by the way, was actually quite prolific from age 31 to 36, averaging 50 HR a year in that span). Aaron would seem to be the best comparison for Pujols – never hitting 50 HR, but consistently hitting 40 or so a year over a long time.
Pujols is a special player, and the 1% probability may seem low, but a lot can happen between now and age 40. The next few years are critical – if he can average 40 HR for the next five years, he will be a year behind ARod’s pace and his probability will go up to 6%.
ARod has by far the best chance by this measure, about 11%. He would have to maintain his recent pace of 30 HR/year for the next five years, and would take longer – past age 40 — if he slows down. The 16 players who have hit at least 150 HR from age 35 on are Bonds, Aaron, Palmeiro, Andres Galarraga, Darrell Evans, Ruth, Carlton Fisk, Ted Williams, Edgar Martinez, Winfield, Jim Thome, Willie Mays, Reggie Jackson, Hank Sauer, Steve Finley and Stan Musial. Even discounting steroid users, there are a number of possible players – including at least two who are hardly Hall of Fame material — who Rodriguez could copy to reach 763.
So it looks like ARod is the favorite to hit 763, but it’s still not likely, while Pujols needs to channel Hank Aaron. This may not be much different than what you thought before, but it’s nice to see it confirmed.
Naturally you can do something similar for other milestones, such as 3000 hits or the 4256 hit total of Pete Rose. Stay tuned for a future article on hit milestones.