Examining the World Series Ballparks

After several days hiatus due to the brevity of the two League Championship Series, baseball returns on Tuesday night with Game One of the World Series. This won’t be the first Series matchup of wild card teams, but it will be the first showdown between non division winners who both won fewer than 90 regular season games. While this Series might lack team and individual excellence compared to many past matchups, it does promise to be quite competitive. Instead of breaking down individual player matchups, let’s take a different tack and examine the venues in which the games will be played – Kauffman Stadium and AT&T Park – to get a feel for the context that will surround the Royals and Giants over the next week or so.

Each year, I calculate my own park factors utilizing granular batted ball data. Actual production in each ballpark is compared to projected production for each park’s respective batted ball mix, using MLB average production at various exit speed/angle ranges. Contact quality is an important variable that is not taken into account in most park factor calculations. Below, let’s take a look at the actual and projected production in all 30 parks, and the resulting 2014 overall park factors, listed from most to least hitter-friendly:

2014 ALL	ACT AVG	ACT SLG	PRJ AVG	PRJ SLG	PK FCT
COL	0.363	0.590	0.331	0.513	126.0
CWS	0.333	0.516	0.307	0.451	123.4
TOR	0.327	0.542	0.315	0.489	114.7
MIN	0.334	0.510	0.317	0.486	110.4
BOS	0.331	0.503	0.316	0.478	110.2
NYY	0.318	0.511	0.318	0.479	106.7
CUB	0.322	0.501	0.316	0.485	105.0
LAD	0.312	0.494	0.312	0.471	104.8
HOU	0.323	0.513	0.322	0.501	102.8
MIL	0.312	0.496	0.315	0.481	101.9
TB	0.303	0.447	0.300	0.445	101.8
TEX	0.320	0.485	0.317	0.484	101.3
CLE	0.320	0.495	0.320	0.490	100.9
CIN	0.304	0.492	0.311	0.476	100.8
DET	0.335	0.512	0.333	0.512	100.7
KC	0.315	0.457	0.312	0.463	99.7
NYM	0.301	0.467	0.306	0.465	98.9
MIA	0.324	0.479	0.324	0.491	97.9
PIT	0.318	0.468	0.317	0.480	97.8
WAS	0.326	0.468	0.328	0.490	95.4
AZ	0.326	0.515	0.330	0.534	95.1
ATL	0.321	0.476	0.322	0.508	93.7
LAA	0.313	0.469	0.316	0.498	93.5
OAK	0.301	0.461	0.311	0.477	93.4
BAL	0.313	0.498	0.326	0.519	92.3
PHL	0.309	0.477	0.317	0.510	91.4
STL	0.305	0.458	0.316	0.487	90.8
SD	0.290	0.429	0.313	0.466	85.3
SF	0.312	0.475	0.329	0.533	84.7
SEA	0.296	0.458	0.318	0.516	82.8
MLB	0.318	0.489	0.318	0.489	100.0
STDEV	0.014	0.031	0.008	0.022	10.0

First, you will note that Kauffman Stadium ranked as a very neutral park in 2014, with a 99.7 overall park factor, while AT&T Park was the second most pitcher-friendly park in the game with an 84.7 overall park factor. We’ll dig a little deeper into those numbers, but first let’s make some general observations.

MLB hitters batted .318 AVG-.489 SLG when they put the ball in play in 2014, batting .275 AVG-.703 SLG on fly balls, .661 AVG-.869 SLG on line drives, and .245 AVG-.267 SLG on grounders. For comparative purposes, hitters batted .318 AVG-.498 SLG on all BIP in 2013, with the higher SLG coming from .284 AVG-.743 SLG on fly balls. The air continues to come out of the game, likely due to multiple factors including the ongoing effects of the game’s stricter drug policies as well as a generally cool summer in much of the country.

Digging a little deeper into the above table, perhaps the most notable factor is the difference in the level of contact quality made in the two World Series ballparks. The projected .312 AVG-.463 SLG in Kauffman Stadium represents the fourth lowest contact quality level in the 30 MLB ballparks, ahead of only Tropicana Field, Citi Field and US Cellular Field. On the other end of the spectrum, the projected .329 AVG-.533 SLG in AT&T Park represents the second highest, behind only Chase Field.

The overall park factors listed above are largely the byproduct of each park’s individual fly ball, liner and ground ball factors. Liner park factors bounce around in a fairly narrow range around 100.0, with a few parks, like the Skydome, getting a boost because of their propensity to allow line drive home runs, while grounder park factors can vary somewhat wildly due to random chance. The primary driver of a stadium’s park factor is its fly ball park factor. A hitter’s park, the vast majority of the time, will have a fly ball park factor over 100, while a pitcher’s park will usually have a fly ball park factor under 100. Below is a list much like the first one, except that this time it is listing each park’s fly ball park factor for 2014:

2014 FLY	ACT AVG	ACT SLG	PRJ AVG	PRJ SLG	PK FCT
COL	0.359	0.967	0.297	0.774	152.2
BOS	0.333	0.779	0.263	0.663	146.6
CWS	0.285	0.756	0.262	0.619	135.7
TOR	0.313	0.844	0.278	0.713	134.8
MIN	0.315	0.748	0.266	0.673	130.2
NYY	0.253	0.748	0.248	0.614	129.3
LAD	0.291	0.768	0.268	0.674	125.1
CUB	0.292	0.709	0.268	0.664	115.9
CLE	0.283	0.749	0.266	0.697	114.6
MIL	0.274	0.739	0.270	0.675	112.5
CIN	0.269	0.758	0.274	0.686	111.6
HOU	0.299	0.798	0.293	0.749	109.7
NYM	0.250	0.637	0.250	0.613	104.5
OAK	0.261	0.652	0.261	0.654	99.7
TEX	0.266	0.664	0.269	0.670	98.1
PIT	0.284	0.691	0.281	0.713	96.9
TB	0.233	0.571	0.241	0.582	95.2
DET	0.257	0.682	0.275	0.698	92.0
BAL	0.278	0.738	0.294	0.765	91.5
WAS	0.249	0.579	0.261	0.633	86.7
PHL	0.311	0.797	0.319	0.883	86.5
MIA	0.259	0.643	0.279	0.717	82.8
KC	0.239	0.567	0.261	0.637	81.3
ATL	0.263	0.646	0.286	0.748	78.5
STL	0.246	0.600	0.271	0.703	76.4
AZ	0.281	0.736	0.313	0.859	76.2
SD	0.213	0.556	0.252	0.632	75.1
LAA	0.261	0.653	0.289	0.779	74.6
SF	0.276	0.654	0.309	0.845	67.3
SEA	0.252	0.660	0.302	0.823	66.2
MLB	0.275	0.703	0.275	0.703	100.0
STDEV	0.031	0.091	0.019	0.077	24.1

This gives us a much better feel for the true nature of Kauffman Stadium. Its fairly neutral 99.7 overall 2014 park factor is inflated by its unusually, perhaps deceptively high grounder park factor of 125.3. While its infield is pretty quick and generally leads to high grounder park factors, 125.3 is at the very high end of its range of potential outcomes. Only two parks, Tropicana Field and Petco Park, had lower actual fly ball production than Kauffman. Part of that is due to the aforementioned relatively poor contact made by the Royals and their foes, and part of it is due to the park.

AT&T Park’s fly ball park factor, likes its overall factor, is second lowest at 67.3, again ahead only of Safeco Field. Interestingly, the quality of fly ball contact made in those two parks was the third and fourth best among the 30 parks, behind only Citizens Bank Park and Chase Field. The Giants and Mariners offenses are both much better than they seem based on their raw, unadjusted numbers.

To provide a bit of context for the numbers we’ve discussed so far, the fly ball, line drive, ground ball and overall park factors for Kauffman Stadium and AT&T Park appear below:

2014	FLY	LD	GB	ALL
KC	81.3	96.6	125.3	99.7
SF	67.3	99.8	85.2	84.7
———–	———–	———–	———–	———–
2013	FLY	LD	GB	ALL
KC	70.0	99.3	105.5	90.7
SF	76.0	99.5	103.1	93.2
———–	———–	———–	———–	———–
2012	FLY	LD	GB	ALL
KC	87.2	106.6	107.4	99.8
SF	87.9	98.4	94.3	94.4

You’ll note that the liner park factors generally hug the MLB average, with KC’s 96.6 in 2014 and 106.6 in 2012 marking the extremes. KC’s grounder park factors are above 100 each season, though this year’s 125.3 was pretty extreme. In contrast, SF’s grounder park factors have been well below 100 in two of the past three seasons, bottoming at 85.2 this season. The fly ball park factors, however, are consistently well below 100 for both ballparks – KC’s have ranged from a low of 70.0 in 2013 to a high of 87.2 in 2012, while SF’s have ranged from a low of 67.3 in 2014 to 87.9 in 2012. Both of these parks are clearly pitcher-friendly, with AT&T Park being a bit more so overall.

Obviously, all parks have their own unique characteristics. Coors Field is at mile-high altitude, driving its 152.2 fly ball and 126.0 overall 2014 park factors. Fenway Park has the Green Monster, keying its 146.6 fly ball and 110.2 overall 2014 park factors. Let’s break down Kauffman Stadium and AT&T Park’s overall and fly ball park factors by field sector to attempt to identify their defining characteristics:

2014 ALL	LF	LCF	CF	RCF	RF
KC	104.0	103.0	103.7	100.8	87.0
SF	81.5	77.5	92.4	81.3	102.3
———–	———–	———–	———–	———–	———–
2014 FLY	LF	LCF	CF	RCF	RF
KC	81.7	72.5	89.8	90.1	77.9
SF	75.0	61.6	75.6	63.8	92.6

Interestingly, Kauffman Stadium was a fairly neutral, even slightly hitter-friendly park to all field sectors except RF in 2014, though it was pitcher-friendly to all sectors with respect to fly balls. The ground ball park factors to LF (134.6) and LCF (161.9) especially were startlingly high. One interesting contributing factor – there were 34 ground ball doubles hit to the LF sector in Kauffman Stadium in 2014, compared to only 14 in AT&T Park. This has more to do with park configuration than with player speed. There were also 41 more singles (in 69 more grounders) hit to the LCF sector in Kauffman Stadium as opposed to AT&T Park – this is due to a combination of more hard-hit grounders getting through the infield and more extremely slowly hit grounders, by both the speedy Royals and their opposition, going for hits.

AT&T Park is an absolute dead zone in the air to both gaps – in fact, the only really safe place to hit a homer there is right down the right field line, provided you get the ball into the air at a reasonably steep angle. The fly ball park factors to LCF (61.6) and RCF (63.8) are among the lowest individual field sectors in the game.

Another way to look at all of this is to examine how each park inflates, or deflates singles, doubles, triples and homers. Below, you’ll see how these parks have affected each type of hit over the past three seasons:

2014	1B PK FCT	2B PK FCT	3B PK FCT	HR PK FCT
KC	102	103	112	85
SF	99	93	194	60
———–	———–	———–	———–	———–
2013	1B PK FCT	2B PK FCT	3B PK FCT	HR PK FCT
KC	103	89	134	76
SF	98	107	166	71
———–	———–	———–	———–	———–
2012	1B PK FCT	2B PK FCT	3B PK FCT	HR PK FCT
KC	103	96	141	88
SF	100	107	142	67

Singles park factors don’t vary much, but the high KC grounder park factors drive its 102-103 marks over the past three years. The most striking numbers on this table are the triples and homers park factors. Both parks, especially AT&T Park, inflate triples by a very significant margin. Since the opening of Marlins Park, it has jockeyed back and forth with AT&T for the title of the most triples-friendly park in the game. As for home runs, AT&T Park’s 60 park factor was by far the lowest in the majors in 2014 – Marlins Park and Busch Stadium were next, tied at 78. Safeco Field, by contrast, had an 84 homer park factor in 2014 – since its fences were brought in for the 2013 season, it has yielded more homers, but its doubles and triples park factors (84 and 56 in 2014) have shrunk.

AT&T Park’s triple and homer park effects come into particular focus in its RCF sector. In 2014, there were an average of 5 fly ball triples hit to the RCF sector in the 30 MLB parks. There were 23 fly ball triples to RCF in AT&T Park. On the other hand, there were an average of 23 fly ball homers to the RCF sector in the 30 MLB parks. There were 5 fly ball homers hit to RCF in AT&T Park. The ball was hit harder to AT&T’s RCF than it was to a neutral park’s RCF in 2014 – but it’s almost impossible to get it over the wall. A homer to most every other park in that sector is a triple in San Francisco.

How can any of this help tell us who might win this World Series? Hard to say, as anything can and often will happen in a short series. I will throw a few notes out there that could give us a clue:

– Using projected production based on contact quality as a guide, the Giants outhit their opponents at home on all BIP by .334 AVG-.552 SLG to .323 AVG-.515 SLG, and on fly balls by .311 AVG-.854 SLG to .307 AVG-.835 SLG. Using the same measure, the Royals were significantly outhit at home on all BIP by .321 AVG-.492 SLG to .303 AVG-.434 SLG, and on fly balls by .270 AVG-.705 SLG to .250 AVG-.565 SLG. Yes, the Royals’ offensive K/BB differential is better, though not dramatically so, but this is a massive gap in relative contact quality between the two teams. Toss in the fact that the Giants get to use the DH – likely getting all of the good things about Michael Morse without having to deal with the bad – and this gap grows even larger.

– The Royals’ outfield defense has been spectacular in the postseason, and has deservedly gathered a great deal of attention. While most advanced metric systems rate the Royals’ defense as superior to that of their opponent’s, adjusting for contact quality makes the Giants’ infield defense look exceptional. In their home games, the Giants batted .264 AVG-.293 SLG on grounders, and “should have” hit .260 AVG-.284 SLG based on contact quality; their opponents actually batted .196 AVG-.212 SLG, and “should have” hit .238 AVG-.259 SLG. That is a massive difference, due to some combination of defensive ability, superior positioning, and sure, some random chance.

The Royals have had a great run, but my gut tells me the several-day layoff has interrupted the considerable momentum fueling their run, and that we are much more likely to see the slightly above average Royals club we saw during the regular season. The Giants’ postseason success feels more real to me, and the irony that the absence of Michael Morse from left field might have gotten them to the playoffs, and his presence as DH could help win them the championship is too delicious to ignore. Giants in five, and may there be multiple triples hit by both clubs.