Baseball Think Factory published a link to this blog entry about guys who have hit 500 home runs or more. Reading it while sipping my morning coffee, I rather flew off the handle, because it's a good example of how not much thinking and a need to expostulate the first thing that comes into one's head can land one in the Realm of Medioticity. What follows is an edited and expanded version of what I posted at the Think Factory.
The problem with this Rant is that it's a very clear-cut example of selective understanding. Take the 'Lively Ball' era, beginning in 1920. By the time Rosey, the blog entry's author, is 6, 5 players have hit 500 home runs, or one every 9.2 years. So, on that basis, by 2009, we should expect there to be 9 or 10 current members. But that masks a slight problem. In 1920, the total number of home runs hit in the same league as where Ruth hit 54, amounted to 369. In Ruth's last 40-homer season, 1932, the AL hit 707 home runs. Logic alone tells you that if more home runs are going to be hit, more players are likely to reach 500.
The next players to join Rosey's Original Five were Mickey Mantle and Eddie Matthews. Let's use Mantle as an example, since he played in the same league and park as the Babe. Mantle first reached the 40-homer plateau in 1956, when he hit 56. The league as a whole (still eight teams) hit 1075! Homers have gone up across the league. That's going to mean more 500-homer careers are coming.
And they did. By the end of 1971, the 500-club had twelve members. One every 4.25 years. So, by 2009, at that rate, we'd expect twenty members. By the time little Rosey is 11, he can expect the home-run club to double when he's fifty.
But wait — there's a big fall-off in new entrants all of a sudden. Between 1972 and 1996, only three more members enter the club. What's going on? We've gone to one every 4.25 years, to one every 5.7 years. By 2009, we should anticipate fifteen members.
Then, 1997 through 2008 (let's leave our latest member, Gary Sheffield, out of this), NINE players enter the 500 club. Everybody is talking about steroid-inflated numbers.
I was doing a little exploration of the rec.sport.baseball archives, and I found an interesting post by notorious sabermetrician Don Malcolm (of Baseball Sabermetric and Big Bad Baseball Annual fame), in which he tallied up a measure of extra-base hits by league. He was making another point, but for my purposes, Malcolm showed how 1950s baseball and 1990s baseball are very similar in terms of extra-base hits. However, in the 1960s we had the Little Deadball™ era, when they raised the mound and fiddled with the strike zone. Then, of course, although they lowered the mound, there was a wave of ballpark building that brought a generation of bigger, artificial-turf, pitcher's parks, in which it was hard to hit home runs. And we got the 'greatest-ever™' era in baseball, the 1969-86 period. At the end of this, after homerriffic 1987, there was some fiddling with the strike zone again, and homers fell off.
The biggest concentration of the 'Roid Era' sluggers in a five-year period comes in 2003-7: Palmeiro, Sosa, Griffey, Thomas, A-rod. Five names. Why am I interested in a five-year period? Because between 1967-71, seven players entered the hallowed halls of the 500 club: Mantle, Matthews, Aaron, Banks, Robinson, Killebrew, Mays.
So, why aren't we asking questions of them? Because we know that some of that power came from the era they played in. The powerful 1950s inevitably led to a sudden jump in the 500 Club in the late 1960s and early 1970s. Likewise, the invention of Homerball in about 1993 meant that we'd be getting a big boost in 500-Club membership right around the middle of the 2000s. And we did. The class of 2005-9 may be a little bit bigger than we have a right to expect, based on the rate of entry to the 500 Club. Some of that may be down to 'drug cheating'. But, as of yet, we've no idea what variance we might expect would be legitimate, because neither Rosey nor I have done a study.
If you know of one, feel free to post a link.