Posted by Andy on November 27, 2007
So, I went back and calculated triples by LHB and RHB for a bunch of years. Click through for lots of analysis.
First, here is the raw data.
LHB AB LHB 3B RHB AB RHB 3B 2007 68335 512 99448 426 2006 66708 493 100633 459 2005 70538 454 95797 434 2004 70981 463 96372 435 2003 79082 475 108367 459 2000 68946 470 98344 482 1995 58151 428 90573 396 1990 59169 417 93466 448 1985 66745 455 93575 510 1980 58602 471 95081 605 1975 58067 407 90554 480 1970 53401 355 95931 572 1965 45639 322 75755 456 1960 34108 270 60198 380
So the first column is year, followed by total at-bats by lefties, triples by lefties, total at-bats by righties, and triples by righties.
Let me mention right up front that I check about the contribution made by pitchers. It affects the data, but only slightly. For a point of reference, in 2007, pitchers had 3347 right-handed ABs and 3 triples, plus 1717 left-handed ABs and 4 triples. It has roughly a 1% influence on the overall rates.
Now, here is the rate data (for all batters including pitchers):
LHB RHB 2007 133.5 233.4 2006 135.3 219.2 2005 155.4 220.7 2004 153.3 221.5 2003 166.5 236.1 2000 146.7 204.0 1995 135.9 228.7 1990 141.9 208.6 1985 146.7 183.5 1980 124.4 157.2 1975 142.7 188.7 1970 150.4 167.7 1965 141.7 166.1 1960 126.3 158.4
So this is number of at-bats, on average, per triple. Obviously, a lower number means more triples. As you can see, it's been pretty consistent for the last 15 years or so, with lefties hitting roughly 50% more triples than righties (on a per AB basis.) Back in the period 1960-1970, the data was also fairly consistent, and the rate of triples was much closer to even, with lefties hitting about 15% more triples than righties.
1980 appears to be a blip, where all batters hit more triples. I don't know if the blip is isolated to year 1980 or to a period around 1980. A fuller study would need to be done.
It's tough to tell the reason for the difference between these two eras (1995 or so to present and 1960 to 1970) but it's tempting to think that the DH has something to do with it. Above, I already noted that the performance of the pitchers themselves doesn't account for the difference. Is it somehow possible that introduction of the DH in the early 1970s has an impact? I don't see how, since we're talking about a lefty-righty difference. I see that lefties get more at-bats these days than they used to. Back in 1960, righties had almost 100% more at-bats than lefties, but these days they get only about 50% more. But since we're looking at rates, the number of at-bats doesn't matter. I am strongly inclined to think that the difference has more to do with defensive strategies.
So let's talk about defensive strategies. I am guessing that outfielders play deeper these days than they used to, since balls tend to be hit further (more doubles and homers.) If so, this would tend to exaggerate the issue raised in the previous post, where rightfielders have such a longer throw to make to third base (as opposed to the throw made by leftfielders) that lefties have an advantage for hitting triples if we assume that both lefties and righties have similar pull tendencies to their own side of the plate.
Here's some data to consider. I went back and looked at triples given up by Cubs pitching at Wrigley Field for all the same years as posted above. As far as I know, the dimensions of Wrigley have stayed pretty constant over the years, so this should eliminate any weird issues such as changing the location of walls, etc. I used visiting players to avoid any particular Cubs who might have been good at hitting triples. Adding together the data for 1995, plus 2000 to 2007, left-handed batters have hit 50 triples in 9825 AB, and righties have hit 56 triples in 15127 at-bats. That's 1 triple per 197 AB for LHB and 1 triple per 270 AB for RHB. So, triples by opposing players at Wrigley have been rarer than league-wide. More importantly, visiting lefties have tripled 37% more (on a per AB basis) than visiting righties at Wrigley. Now, in the 1960-1970 period (considering just the 3 years 1960, 1965, and 1970, as above), visiting lefties hit 30 triples in 3259 AB and visiting righties hit 41 triples in 5346 AB. That's 1 per 108 AB for LHB and 1 per 130 AB for RHB. So Wrigley was actually an easier place for visitors to hit triples than league average in the period 1960-1970. The important number, though, is that lefties hit triples at a rate 20% higher than righties.
So the basic question is: why (at Wrigley) do visiting lefties hit 37% more triples in the current era, but hit only 20% more triples in the 1960-1970 era? The only answer I can come up with is defense. Now, it could be defensive alignment (i.e. playing deeper) or it could be specific Cubs outfielders...for example Sammy Sosa giving up a lot of triples to right field, which I find quite believable. But that wouldn't explain the league-wide difference that we've seen unless modern rightfielders are just worse at preventing triples than their older counterparts.
Now one more piece of data. In 2007, there were 938 triples hit overall. 428 of them were fielded by the RF, 391 by the CF, and 118 by the LF. (One was fielded by the 2B, which I'm sure was a line drive off his glove that went to the outfield.) Right away, you see the evidence that more triples go to right field, which would seem to really favor lefties. The overall percentages were 45.7% to RF, 41.7% to CF, and 12.6% to LF. For LHB, they hit 253 to RF, 195 to CF, and 63 to LF. That's 49.5% to RF, 38.2% to CF, and 12.3% to LF. For RHB, they hit 175 to RF, 196 to CF, and 55 to LF. That's 41.1% to RF, 46.0% to CF, and 12.9% to LF.
So RHB actually hit the most triples to CF, whereas LHB hit the most to RF. This is more evidence in support of the RF vs LF theory for triples, and since batters pull most often, it definitely favors lefties hitting more triples.
What did I miss?