Daily MLB Tips: Ballpark Factors

Jonathan Bales is the author of Fantasy Baseball for Smart People—a guide designed to help you profit on DraftKings.

My daily fantasy baseball research is basically broken down into two main categories based on whether or not the data is static or flexible. Examples of the latter type of information include lineup cards, weather, and (to a degree) the Vegas lines. All of those variables must be monitored prior to the start of DraftKings contests.

Then there are more static inputs that can be researched at any point during the day, such as a batter’s historic success broken down by pitcher handedness, the matchup quality, and—the topic for today’s article—the ballpark.

The stadium in which a game is being played is of massive importance when projecting players. Due to various factors (such as a city’s weather, the orientation of the stadium in relation to the sun, and the particular dimensions of the park), some ballparks are simply better or worse for batters than others. We all know this to be the case with the Coors Field effect. There are obvious benefits for hitters in playing in the thin air in Colorado, so it’s no surprise that Coors Field is by far the most advantageous ballpark for batters and the worst ballpark for pitchers when it comes to bulk fantasy production. Even forgetting Coors for a moment, there are other parks that are simply much better for batters than others.

Last Season’s Top Ballparks

Here’s a look at the top 10 ballparks on DraftKings last season in terms of the average points scored for lineups that stacked a team (minimum four batters) in that particular park.

With an average of 106.4 points, lineups that stacked a team playing at Coors Field were head and shoulders above the rest of stadiums. Nearly 1-in-11 GPP winners stacked a team at Coors, which is pretty amazing considering the ceiling on that number is 50 percent since the Rockies play half their games on the road. As far as cash games go, it’s pretty apparent that you need to consider the teams at Coors very strongly if your goal is point-maximization.

Of course, there are two other variables to consider when thinking about who to stack and where to stack them: cost and ownership. As far as cost goes, batters at Coors Field were clearly underpriced in 2014; if they cost more, overall lineups would have been worse and the average score wouldn’t have been such an outlier. The affordability of those bats allowed lineups with teams stacked at Coors to outperform other parks by a wide margin.

However, the prices of many batters playing in Coors have been higher on DraftKings this year. The site is simply accounting for situational effects to a stronger degree than ever before. I think we need to wait and see how things play out in terms of the data to determine if stacking Coors Field is still a profitable strategy. Ultimately, it will totally come down to that pricing.

Then there’s ownership. Even with all of the points scored and all of the winning GPP lineups at Coors last season, the ballpark was not the best in terms of GPP profitability. One thing we need to keep in mind is that these are two totally different questions:

1) Which ballpark is most likely to be the stacked by a winning GPP lineup?

2) Which ballpark leads to the highest probability of success for a single lineup?

These are two very different questions which boil down to not only park effects, but also player/team usage. Since Coors Field is stacked so heavily, it will always have the highest probability of being the park that’s stacked in a winning GPP lineup. The sheer number of lineups with the Rockies or their opponent will ensure that to be the case.

However, if you look at the percentage of lineups that won tournaments last year, you see that Coors Field was actually tied for second place behind Marlins Park. Despite there being nearly five times as many winning lineups with teams playing at Coors Field, it was actually Marlins Park that led the league in terms of the odds of any single lineup actually winning a tournament. PNC Park tied Coors Field as a close second. I’d guess that, if prices on players in Colorado remain high, Coors Field will actually rank outside of the top three this year.

The important point to keep in mind is that while point-maximization might be smart in cash games, you need to consider not only park factors in GPPs, but also the public perception of park factors. Everyone knows Coors is the shit, but few realize how profitable it can be to stack teams playing in Miami or Pittsburgh. By balancing those two things, you’ll find the most GPP success as it relates to determining not only which teams to stack, but where to stack them.