In the game of baseball, environment often plays a role in determining a player’s worth. For example, a pitcher who is skilled at inducing groundballs may be more valuable than his flyball-prone counterpart in a home-run-happy ballpark like Coors Field. This same pitcher will be less valuable, though, if he plays on a team like the Detroit Tigers that has a porous infield defense. Or consider a position player who is gifted with the bat but has a poor glove. This player isn’t much of a problem in the American League because of the DH rule, but in the National League, a player with fielding deficiencies often has nowhere to play (just look at Jim Thome this year).

In other words, value is often about context. The same holds true in fantasy baseball, although it’s a factor that’s considered less frequently. Often, we pretend we’re all playing the same game. We’re not.

Let’s take an example: Eric Hosmer or Carlos Pena—who was more valuable in fantasy baseball leagues last season?

Many people might immediately assume Hosmer. In 2011, his batting average was 70 points higher than Pena, he stole 11 bases, and he held his own with Pena in runs and RBI. Certainly, most people drafting for 2012 think Hosmer is the more valuable of the two. According to Mock Draft Central, Hosmer is being selected with the 52nd pick, on average, whereas Pena is being drafted around the 223rd pick.

And yet, in leagues that count on-base percentage instead of average, Pena was statistically more valuable last season. In a $260 5×5 league where 66 percent of the money goes to hitting, all else being equal, the difference between counting AVG and OBP as categories is thus: in AVG leagues, Hosmer’s 2011 stats translate to a $22 value whereas Pena’s 2011 stats translate to a $13 value. But in OBP leagues, where players who know how to take walks are boosted in value, Hosmer’s 2011 stats translate to a $17 value whereas Pena’s 2011 stats translate to a $24 value. Quite a difference.

This league format isn’t unusual in the slightest, but admittedly, most fantasy baseball leagues don’t custom format their league to include an “exotic” category like on-base percentage. Still, even when leagues accept a given fantasy service provider’s default setup, competitors face wildly different formats that sharply influence player value.

For example, many competitors choose to play fantasy baseball on CBS Sports, whose standard format is a points-based system that rewards positive outcomes like hits, quality starts, and steals while penalizing negative outcomes like blown saves, losses, and times caught stealing. Many other competitors choose to play fantasy baseball at ESPN, where the standard format is a 5×5 category rotisserie league.

One need only glance at the 2011 player rater for each of these two services to note the differences. On ESPN, for example, Starlin Castro ended last season as the 23rd ranked batter in standard leagues. On CBS, he finished as the 45th. Similarly, Elvis Andrus, Shane Victorino, and Brandon Phillips did better on ESPN. Why? Simple. One format (ESPN) gives more value to the runs category than the other (CBS).

The same player, the same statistics, and yet the value of the players can vary wildly depending on where you play. This is very important.

Last week, I wrote about the popular preseason exercise of picking “sleepers,” or potential breakout players, and why the paradox of giving hype to the supposedly non-hyped might steer competitors wrong. The fact that values are so relative from one format to another opens up another can of worms: how is it possible to formulate a preseason ranking of the best players to roster when values differ sharply from one format to the next?

Similar to last week, I must again discuss the biases of the content business. This time, it has to do with the fact that those who dish advice want to be generally appreciable. This is both understandable and necessary. To be popular and to attract readers means finding commonality. Any advice that is specifically geared to competitors who play on CBS Sports’ website, for example, risks alienating those who play on ESPN’s. But even if writers could target their niches, and some try, there are still obstacles towards conferring advice that is useful to individuals rather than the general masses.

Let’s consider: I don’t know you. I don’t know the type of league you compete in. I don’t know how many teams are in your league and how active your leaguemates are. I don’t know roster flexibility in your league. I don’t know whether you must start two catchers or merely one, and I don’t know, when a player gets injured, how easy it is to replace a player through a free agent addition or through a trade in your league.

All of these things have a tremendous impact on player valuations. Even if it was possible to project the 2012 season with the foresight of the Oracle of Delphi, it wouldn’t mean that any baseball analyst could immediately tell readers which players are more valuable than others. Again, it all depends on context.

To show this, let’s use BP’s Player Forecast Manager, which translates PECOTA projections into customized values, depending on one’s league format.

Here, we’re going to look at two different leagues. Both leagues are identical except for one major difference. Both leagues assume a $260 budget where $180 goes to hitters and the rest to pitchers. Both leagues use the most popular 5×5 categories (HR, R, RBI, SB, AVG for hitters; ERA, WHIP, W, K, SV for pitchers). Both leagues use two catchers, a middle and corner infield spot, and five outfielders. And so on. The only difference between the two leagues is that one has 12 teams and the other has 16 teams.

Here’s a graph showing the projected values of players across these two leagues. See the differences?

A different size league shakes up the amount of scarcity at the different positions. It also impacts the compositional value of stats like home runs versus steals.

In the smaller 12-team league, according to PECOTA, the top five players are ranked as: 1) Ryan Braun, 2) Albert Pujols, 3) Jacoby Ellsbury, 4) Miguel Cabrera, 5) Ian Kinsler. In the larger 16-team league, according to the same projections, we have a different ranking: 1) Jacoby Ellsbury, 2) Ryan Braun, 3) Albert Pujols, 4) Ian Kinsler, 5) Matt Kemp.

Indeed, according to this review, slugging first basemen are more valuable in smaller formats compared to larger ones. The four players who are most boosted in a 12-team league compared to a 16-team league are Pujols, Cabrera, Adrian Gonzalez, and Prince Fielder. Meanwhile, in a 16-team league, speedy outfielders and mediocre catchers get a value boost. The 10 players whose projected value rises most in a 16-team league compared to a 12-team league are Nyjer Morgan, Salvador Perez, Brett Gardner, Josh Thole, Carlos Ruiz, Chris Iannetta, Miguel Olivo, Coco Crisp, Michael Bourn, and Jose Tabata.

This knowledge is very important in fantasy competition. There are things we’re told. There are things we aren’t sure about. And then, there are things we have good reason to believe.

We hear, by most accounts, that Eric Hosmer is a rising player who should be valuable in fantasy leagues this coming season. Exactly how good he’ll be is somewhat unclear. If Hosmer meets his 50th percentile target, by PECOTA projections, he’ll be hitting .284/.335/.443. If Hosmer experiences an even bigger breakout and meets his 80th percentile target, he’ll be hitting .312/.365/.487. The crowds have weighed the evidence and clearly deemed Hosmer to be worth a nice price at drafts and auctions. The difference between his 50th and 80th percentile will determine if the bet pays off.

It remains to be seen what Hosmer actually accomplishes, but there are certain things we know for sure. Play in a league with more teams? Compete in a league that counts OBP instead of AVG? In both cases, a player of Hosmer’s ilk faces environmental hurdles that will make it much tougher to live up to his draft value.

In a perfect information game, there are no secrets. However, that knowledge parity doesn’t necessarily mean there’s equality in the skills necessary to build a roster and manage it to full advantage. We might all come to a near consensus about which players are better than others, but the ability to contextualize and figure out how the information is personally relevant is one of the driving factors towards competitive success. And for now, the fact that analysts steer readers towards general wisdom when the signs point to context-specific value being just as (if not more) relevant opens up fortunate opportunities for those smart enough to figure this stuff out.