Daily Fantasy Baseball: An Introduction to Using Park Factor

Park factor is an issue unique to daily fantasy baseball. How should we factor it into our decision-making?

Scene: it's the fourth quarter of an NFL game between the New York Giants and the Philadelphia Eagles.

You've been watching this game all night after having stacked Eli Manning and Odell Beckham, hoping to capitalize on the Eagles' weak secondary. If you can just squeeze out one more touchdown, you're buying that pool your kids have been begging for the past three years.

Manning drops back to pass. You see Beckham sprint past his defender, setting himself up for an easy touchdown.

Manning lobs the ball down the field with just the perfect amount of air to lead Beckham into the back corner of the end zone. Beckham extends his arms toward the ball, and you extend yours toward the sky, ready to celebrate.


Instead of running you into pools of cash, Beckham ran into the wall that was positioned three yards into the end zone at that stadium. The Giants lose, you sob uncontrollably, and Little Suzie doesn't get a new place to play with her duckies.

Park factors are an issue we don't have to deal with in many daily fantasy sports. You have the slight bump of playing in a dome in the NFL, and there are score-keeping discrepancies at some NHL arenas, but outside of that, most things are largely uniform. Things are radically different in MLB DFS.

Here, park factors will be one of the top things you'll have to consider on a nightly basis. You can love Chris Sale all you want, but if that puppy's headed to Coors Field, it might be best to stay away.

Let's run through what we mean when we discuss park factors before dissecting the various aspects of a park factor and how it should affect your decision-making in daily fantasy baseball.

What Are Park Factors?

Broadly, a park factor measures how conducive one ballpark is to offense relative to the rest of the league. If runs scored are more abundant at one park than they are at another, that would seem relevant for fantasy, no?

There isn't a set-in-stone place you must go for park factors, but my general landing spot is ESPN's park factor page. This includes breakdowns for park factors for runs, home runs, and several other categories, all of which help us better understand the true impact of the venue.

The only downside of this list is that it's based on just one year of data. That limited sample size can lead to some heavy year-to-year variance, which is no bueno for our purposes.

To combat this, I combined the lists from 2013, 2014, and 2015 and put them in this Google doc. I only included the run park factors and home run park factors as those are the two that I use most for DFS purposes, though you can certainly gain something with knowledge of the other categories.

Weighing Park Factors Into Decision-Making

So you've got the park factors in front of you, and you know how each park stacks up. Now what?

Clearly, you'll most often want to target parks that have traditionally been more prone to runs. More runs mean more runs scored and more RBIs, both of which will help you rake in the points. That's simple.

The flip side is that you'll also want to make sure your pitchers are in spots in which they can succeed. Does this mean you can never use a pitcher in the thin air of Colorado? Absolultely not, and it can sometimes be a fun strategy in a tournament as that pitcher will come at a heavy discount. It's just not something you'll want to do often or in cash games at all.

There is nuance to this, though, as not all park factors are the same. Go back to the Google doc link above to see what I'm talking about.

One thing you'll notice is that there isn't a heavy amount of cohesion between the run park factor rankings and those for the home run park factors. Fenway Park is second for overall park factor, but it drops to 24th for dingers. Why is that?

A lot of this has to do with the dimensions of the park. The Green Monster allows Fenway to bask in doubles, but it means a ball with low trajectory going to left field has no shot at eeking over the fence. That creates a gap between the the two rankings.

Then you look at Arizona's Chase Field. Because it's in a desert, and warm temperatures aid the offense, the gaps in left- and right-center field were built incredibly deep, and there is a giant wall in center field. This isn't great for home runs, but the extra outfield grass does allow an abundance of doubles and triples. That's clearly going to help out your DFS rosters, even if it's not a home run.

I will certainly look at home run park factor when I'm making my batter selections, but I weigh it more heavily when I'm selecting my pitchers.

Let's say Max Scherzer is on the road to face the Philadelphia Phillies. Scherzer is a truly dominant pitcher, but he is also a heavy fly-ball pitcher. Philadelphia was the most homer-friendly park on our list. How should we handle this?

For me, it depends. If the Phillies' offense is struggling as much as it did in 2015, then I'm not going to rule Scherzer out, though I will slightly lower my valuation of him. If he's in Yankee Stadium -- second in home run park factor -- and facing a more potent lineup, then I'll likely stay away.

The flip side of this is that fly-ball pitchers who play in homer-friendly parks could find additional value when their teams hit the road. For example, Jon Gray -- a highly-touted Colorado Rockies prospect -- made his debut in 2015. He allowed 19 earned runs over 20 2/3 innings at home, but he was effective on the road, allowing only 6 runs in 20 innings.

These players are likely to have minuscule salaries, so if you can pinpoint when they'll pitch well on the road, it could be very much to your advantage.

In Closing

We'll certainly go further in-depth on park factor in other pieces as it should be a considerable portion of your process. Let's just skim through the basics for now.

You should be using park factor when selecting your batters. This will be reflected in their pricing (specifically a significant price hike when a team is at Coors Field), but that doesn't mean you should simply disregard it. Just because their price may be higher doesn't mean it'll be high enough to negate value.

This also means lowering your valuation of players who are in parks that are not conducive to runs. The extreme example is when the Rockies head to San Francisco, going from the best park factor to the worst, but it's something you should always be considering, regardless of the two teams involved.

Your consideration of park factor should be just as high for pitchers as it is for hitters. Clayton Kershaw pitching in Los Angeles is much different than Clayton Kershaw pitching in Phoenix. It doesn't rule these guys out of consideration, but their value does fluctuate significantly.

Finally, make sure to use a pitcher's profile to decide how home run park factor will affect them. A fly-ball pitcher starting in a homer-friendly park is going to be a cause for concern, while a ground-ball pitcher may not face any issues at all.

Park factor is something we don't see in other sports. However, it is one of the most important factors to consider in daily fantasy baseball. This isn't something people don't know about, but by prioritizing it more highly than others, you can provide yourself with an advantage over the competition.