The basics of park factors, and their effects on fantasy baseball, are known to just about everybody by now. (If by some chance you know somebody who’s out of the loop on the concept, please drop me a line when there’s an opening in their league.) Colorado hitters good, Colorado pitchers bad. Rangers hitters good, Dodgers pitchers good, etc., etc. Even if you don’t bother to crunch the actual numbers, the trends are pretty much part of fantasy conventional wisdom.

But a player’s home ballpark only applies to half their games. What about the other half? Road games never enter into the equation. Conventional wisdom says that a team’s away games are fairly evenly distributed, and the aggregate impact of all those different road parks will even out.

With the unbalanced schedule, though, teams end up playing nearly half their road games–in other words, a quarter of their schedule–against the other teams in their division. (The actual percentage varies slightly for the misshapen step-siblings NL Central and AL West.) While those games are split up among a few different stadiums, if most or all of the parks in a particular division trend a certain way the cumulative effect might be worth noting.

So let’s test this hypothesis. Using the same park factors James Click used for his recent Crooked Numbers articles (with one little addition of my own) let’s see if the unbalanced schedule unbalances things just a little more than we previously thought. Let’s see, in feng shui terms, whether roto owners looking for pitching should face East or West, or whether seekers of hitting should maintain a Central focus.

First, a disclaimer: while the AL parks as a group have been fairly stable the last few years (some shifting outfield fences in Chicago and Kansas City excepted), the NL saw the addition of three new ballparks (in Cincinnati, Philadelphia and San Diego) in two years, which makes the sample size on their park factors lass than ideal. On top of that, the ex-Expos will now be moving into a brand old ballpark in RFK Stadium, the previous home of the second incarnation of the Senators.

Fortunately, Retrosheet is there to save the day. Using the last three years of box scores (1969-1971) from the days before there were Rangers, I cobbled together some park factors for RFK, which will be using the same outfield dimensions that it did back in the day. Of course, the late-’60s/early-’70s AL is a very different run environment than the NL of the ’00s. So I also cobbled together ’69-’71 park factors for three ballparks that have stood relatively unchanged from then until now (Wrigley Field, Fenway Park and Shea Stadium, the last of which has undergone less tweaking over the years than Busch Stadium or Chavez Ravine) and used the difference between the eras as reflected in the evolution of those park factors to “age” the RFK numbers. It’s far from perfect, but it will have to do until we have some modern RFK data.

The long and short of it is, the AL numbers are going to be more trustworthy than the NL numbers.

From a fantasy perspective, if there’s a noticeable pattern across a division the best place to try and cash in on it is with a late-round sleeper/cheap end-of-auction purchase. The top roto producers, for the most part, have established performance parameters that account for their price tag, and no matter how extreme a shift in home park might be it rarely impacts their draft round or auction price–with the exception, of course, of Coors Field. (Try to get Carlos Beltran, who’s played in hitters parks his whole career and is now moving to a pitcher’s park in Shea, at a discount if you don’t believe me.) With sleeper types, however, you often have a number of similar options from which to choose (which young, talented, injury-prone pitcher should I select now?) and knowing whether they are boosted or hindered by park factors in 72% of their games can help narrow the field greatly. Essentially, this is the margin play–all else being equal, this is something you can use as a tie-breaker.

AL East

From a ballpark perspective, the AL East is the most balanced division in baseball. No one skew (aiding or suppressing hits, aiding or suppressing home runs etc.) is present in any more than three of the five yards, and no ballpark in the division features anything close to the extreme effects of a Safeco Field or Coors Field. As a result, the unbalanced schedule makes the division’s park factors even more of a homogenous glop; aside from being uniformly unfriendly to triples (even Tampa Bay, which gives the triple a small but noticeable boost at home, becomes a very slightly negative three-bagger environment once the divisional games are factored in) the ballparks of the AL East, as a group, are about as neutral as can be. Thanks to Camden Yards and the Rogers Centre (neé Skydome) home runs have a slightly positive factor, and Fenway drags hits (and therefore batting average) just into the positives, but that’s about it.

Tropicana Field does emerge as one of only four AL parks to suppress both batting average and home runs, even if both effects are relatively small, which could bode well for a Chad Orvella or Dewon Brazelton.

AL Central

The 2004 power explosion at U.S. Cellular Field in Chicago was impressive, but with three homer-suppressing parks doing their thing, the Central is the most home run-unfriendly division in the junior circuit. Comerica Park in Detroit, Jacobs Field in Cleveland and the Metrodome in Minneapolis all jealously hoard souvenirs. In fact, while Comerica earns its rep as a homer-killer, Jacobs is right behind it in effect–a fact your competition might not be aware of. The division as a whole does inflate batting averages, however, thanks mainly to Kaufmann Stadium in Kansas City.

AL West

The AL West features one of the few shocking reversals of the Conventional Wisdom I found. Safeco Field is one of the most notorious pitchers’ parks in the majors, and yet, once the unbalanced schedule is factored in, Seattle players actually face a very slightly advantageous home-run environment. Being a Mariner still kills your batting average–it is, by far, the biggest hit suppressor in the AL–but the lack of a drag on home runs is good news for Adrian Beltre owners.

As a group, the AL West is a juicy source of power. Only Edison Field in Anaheim acts as a home-run suppressor, while both Texas and (surprisingly) Oakland get nice air under their fly balls. There’s a trade-off in batting average though. Texas still inflates hits (the Rangers have the best hitting environment in the AL) but the other three parks, led by Safeco, spell leathery death for balls in play.

NL East

My jerry-rigged park factors for RFK Stadium show an environment that figures to be one of the stronger pitchers’ parks in the NL. Back in the Senators’ last days, RFK played at a slight advantage to pitchers, suppressing home runs while giving a few runs back in triples. That, however, was during a time when Fenway and Wrigley were two of the strongest hitters’ parks in the land. Today those venerable edifices are much closer to neutral, while over that same period Shea has gone from a pitchers’ park to a different kind of pitchers’ park, now killing home runs instead of batting average. There’s no reason to think a similar impact will be felt in RFK; my best guess is a park that plays somewhat like SBC Park in San Francisco, but without the triples.

One other odd pattern emerged while I was looking through the box scores on Retrosheet: extra-base hits simply disappeared at RFK in the late summer. Over the three-year period I drew the sample from, 1969-1971, opposing teams averaged about 2.25 extra-base hits per game at RFK. Over the period represented by home games 42 through 69, however (roughly the start of the second half through to the end of August), that number drops to 1.75. The Senators didn’t fare much better. It could be a sample size fluke… or then again, it could be something in the muggy Washington summer air. Don’t be too shocked if Zach Day rides his sinker to a sub-2.00 ERA in July and/or August this year.

As a division, though, RFK will be right at home in the NL East. If you’re looking for pitching sleepers, this is the place to shop; all five parks suppress batting average, with Florida coming in at #2 in the majors behind Seattle with the unbalanced schedule factored in. Four of the five teams play in home run-suppressing environments. Atlanta, which gets a small positive home-run boost at home, gets dragged down below the water line by their divisional foes. The one outlier is Citizens Bank Park in Philadelphia, one of the three parks with less-than-full sample sizes yet.

Whether it’s Pedro Martinez, Josh Beckett or Tim Hudson, look for an NL ERA champion (and likely the Cy Young winner too, even if they’re not the same person) to come out of the East.

NL Central

Sample-size issues with the Great American Ballpark notwithstanding, the NL Central looks a lot like the AL West–some nice home-run boosts, but a general drag on batting averages. Minute Maid Park is one of only three stadiums in the NL to boost both home run and batting average (although it has the least impact among the three) while Busch Stadium’s recent factors would make it right at home in the NL East. And Wrigley is still the best NL home run park east of the Rockies, although it’s not the launching pad it once was or, indeed, that its cross-town rival U.S. Cellular is now.

NL West

The NL West ballparks stare at each other across a great divide. On one side is Coors Field, of course, with Bank One Ballpark in Arizona peeking over its shoulder; on the other side stand SBC, Petco and Dodger Stadium, each doing its part to make pitchers feel welcome. The end result, once the unbalanced schedule is factored in, is exactly what you’d expect: fewer extremes all around.

In total, the NL West is a hitters’ division. Coors casts a long shadow, and Dodger Stadium has shown a recent propensity to boost home runs, despite an overall decline in hits. SBC displays the opposite tendency, surrendering singles while swallowing homers. Only Petco, tiny sample size and all, stands as a true pitchers’ park. If Petco loosens its grip on hitters over the next couple of seasons, the NL West should strengthen its hold on the title of Best Hitters Division in the Majors.

Overall, the impact of the unbalanced schedule seems pretty muted, with only the NL East producing any kind of “feedback loop” among its parks. The two most radical changes are in Atlanta (which drifts from a HR-friendly environment at home to a chilly longball environment once divisional games are included) and Seattle (which trends in the opposite direction).

It might be interesting to take a look at these numbers again in a few years, once the new stadiums have a chance to establish themselves. The RFK factors in particular could undergo a big change, as the ones I used here rank as only a bit more reliable than a guesstimate.

In fantasy terms though, the key places to look for hitting sleepers would seem to be the NL West, while both Easts might be your best hunting ground for pitching bargains.

Erik Siegrist is a beat writer for RotoWire, covering the Marlins, Nationals and White Sox. He can be reached here.