Baseball Musings
Baseball Musings
April 20, 2007
Record Pace?

Marc Normandin was conducting a BP chat today and forwarded me this question:

Based on the enormous sample size of like 14 games do you think A-Rod will break Bonds' single season home run record?

Here's my answer:

For his career, Alex Rodriguez hits home runs at a rate of 6.9 per 100 at bats. If he gets 600 AB this season, he'll get another 543 at bats. So if he reverts to his career norm for the rest of the season, he'd hit another 38 home runs, giving him 48 for the year. However, the chance of someone who hits home runs at a rate of .069 hitting at least 10 HR in 57 at bats is .005, which is significant at the .05 level. So there's some evidence that A-Rod is better than his career numbers this season. If you average the two rates, you get .122, which works out to 73 home runs. My feeling is that he's better than .069 right now. How much better is the question. My gut is he's more likely to hit 50 than 70.

Another way to do it would be to find the lowest rate that's not significant at the .05 level. That rate is .0985. If he were to hit at that rate the rest of the year and come to the plate for 600 AB, he'd hit 63 home runs, breaking the AL record.


Posted by David Pinto at 05:36 PM | Records | TrackBack (0)
Comments

This isn't as "scientific" but if you look at AROD's previous best season in terms of ab/hr rate, it was 2002 when he hit 9 homeruns every 100 at bats. If you extrapolated that rate to 540 at bats (after his first 3 at bats today) and added it to his now 12 homeruns, you get 61 hrs.

I think this shows how truly impressive plus 60 homerun seasons are. If you take a ridiculous stretch like AROD's first 15 games this year and then add on the best homerun rate for arguably one of the best players ever, you still get "only" 61 hrs. That was pretty surprising to me, and I expected the number to be higher.

Posted by: Chris at April 20, 2007 09:16 PM

I think his lineup is a terrific asset to him too. Although he's hitting well enough to justify being walked, he'll have runners on base all year, and he'll have very good hitters behind him all year.

Bonds was walked 177 times in his 73 homer year. ARod wouldn't need to quite match Bonds' hr ratio if he gets pitched to 90 more times than Bonds was.

Posted by: notsellingjeans at April 21, 2007 12:13 AM

The AL record is the MLB record as far as I'm concerned. If A Rod goes on to hit 62+ home runs this year, he's the record holder in my eyes. I refuse to recognize Bonds' record, and I no longer acknowledge McGwire of Sosa's achievements as well. Impressive seasons as they were, I have large asterisks next to each of those now. Just my personal opinion.

Posted by: Jason at April 27, 2007 02:32 PM
Post a comment









Remember personal info?