The Dangers of Recency Bias

So you just finished watching Scott Stallings take down the Farmer’s Open Championship and you begin to look ahead at building your squad the following week for the Waste Management Phoenix Open, another of the many sexy sponsor names for tour events. As you begin to scroll through the weekly prices for the tournament, the first name that comes to mind: Scott Stallings. He flew under the radar last week as his ownership level hovered in the low single digits and the handful of players who had him in their lineups fared quite well as this isolation play helped to catapult these squads to the top of the leaderboard. Of course, you notice that the price to add Mr. Stallings has leapt by about 20% from the previous week to account for his success from his victory, but like most rubes, you are undeterred and punch the draft button triumphantly, making him the cornerstone of your roster for the week.

As Friday afternoon of the Phoenix Open comes to a close, you flip through your phone to check to see if you hit that magical miracle of getting all 6 players through the cut and you see the two ugliest letters imaginable next to none other than one Scott Stallings: MC – Missed Cut

What just happened here? He played so brilliantly just a week before and then Friday afternoon he clearly forgot to bring his putter with him on holes 10-12 bogeying 3 in a row and falling below the magic cut line for the weekend. As you melt down into a fit of rage, cursing your terrible luck and bringing your secretary running into your office to save you from an apparent seizure, you remember back to reading an article about recency bias and its affects on becoming successful in fantasy sports, particularly fantasy golf.

The events above play out all the time for daily fantasy sports players, particularly those that watch each week as a fan instead of through the lens of a statistician. This is terribly apparent in football where ownership of certain players rises and falls more dramatically than most stocks trading on Wall Street. I could list dozens of examples from this past season, but for golf, what’s most interesting is that this bias tends to gravitate around the winner of the previous tournament in particular, so that is where we chose to focus our research.

We wanted to see how the winners of each tournament fared in the event following their victory to see how a win in the previous week affected the results in the next event that the victorious player participated in. We took data for the last five years covering 224 events and found some interesting results along the way that lead us to surprising conclusions.

 

We conclude that fading the previous tournament’s winner is typically a useful strategy when you begin to construct your squad for the upcoming tournament.

To make things simple, I focused on 5 different placements for each player:
1) Missed Cut
2) Top 10 Finish
3) 10th-20th Finish
4) 20th-30th Finish
5) 30th and beyond

From 2010-2014, 21% of players that won an event failed to make the cut at the next event that they played in. That’s a startlingly high number to a lot of readers, but not entirely unpredictable. Whether the large paycheck makes certain players more relaxed or securing a tour card for another year allows for some to let their foot off the peddle a bit, I can’t exactly speculate, but what is certain is that there does tend to be a bit of a dropoff in play the week after a victory. For the most part, players simply revert back to the mean with their play so that a middle of the road player like Scott Stallings more than likely will play pretty closely to his average in the week following a victory, which in Scott’s case was making the cut a paltry 12 times out of 28 events.

Now, Stallings was used to illustrate a point, but this happens to top level players as well. Top names like Phil Mickelson, Tiger Woods, Bubba Watson, Justin Rose, and even a young Rory McIlroy in 2010 have achieved this dubious feat. Of course, several of those names have also been on the other end of data by placing in the Top 10 the following week. In fact, 18% of winners actually placed in the Top 10 in the next event they played. The data is only slightly tilted in that Rory achieved this feat 4 of the 41 occurrences. This raises the question of how momentum seems to affect certain players, but I will leave that for another column and for those interested in hearing about things like standard deviation, correlation coefficients and R-squared. A handful of you just yawned right there and that’s okay, too. I don’t like it anymore than you do.

What I will say is that there is a golfer that comes along about every decade or so that seems to defy most trends. Tiger Woods is a great example where winning one tournament seemed to make him even more determined to win the next and he seemed to will himself to victory after victory. Although Tiger’s time as a dominant champion seems to be fading quickly, Rory McIlroy seems to be of the same ilk where winning one tournament actually makes him more likely to be in the hunt the following week. Always tread lightly when making the decision to fade a player like Rory, who we would label as a generational talent, as this is likely to lead to much bigger swings in your bankroll.

Finally, the other compelling piece of data that we found to be useful was how often players that won finished outside of the Top 30 in next event they participated in. 29.5% of players made the cut, but finished outside of the Top 30. If you look at the number of players who won and then either missed the cut or placed outside of the top 30, you see that it comes out to just over 50%. So over the last 5 years, if you had picked the winner of the previous event to be on your roster, you experienced a good deal of disappointment from rostering said player, basically a coin flip.

We here at Fantasy Golf Insider don’t want to make bets on coin flips. As our poker days have taught us, avoiding this scenario as long as possible and keeping the odds on our side is one of the main keys to riding out the variance in games of skill like fantasy sports. While we are not advocating that you fade the winner of the previous tournament outright, we do suggest a measured approach when deciding whether or not to include him in your lineup. With the big increase in salary that (usually 10-20%) arises from a player winning an event, it is key to understand if the player still has value at his new price. Has he played well in the upcoming tournament in years past? Is he playing well this season or did this victory seem to come together from a wild convergence of events? Has he been limited by any outside factors like injuries or personal issues? And of course, what are the oddsmakers saying in comparison to the price that is being offered?

Essentially, when analyzing this player, view the victory as neutral factor towards selecting the player, the price increase as a large negative against taking the player, and be extra diligent in doing your research and looking at the numbers to see if the player is still a solid value for your roster given the new premium in price. You can count on the fact that this player will be more widely owned in his next event, so be very careful when following the masses as winning tournaments typically boils down to finding ways to differentiate your squad from the rest of the field. Typically, owning this player will give you no real edge over competitors when he performs well and may very well ruin your chances of winning in those many instances where he reverts to the mean. Typically, we recommend a pessimistic approach towards the previous tournament’s winner, taking the attitude that you should fade that player unless the statistics overwhelmingly support his higher price and higher level of ownership among other players.
Zach Turcotte is a co-founder of Fantasy Golf Insider.com, fantasy golf expert and has been following and writing about fantasy golf for over five years. He is a member of multiple season long fantasy golf leagues as well as an avid daily fantasy golf player. In the past 12 months he has won over $13,000 playing fantasy golf on Draftkings.com as myzteriouzly. Feel free to contact Zach at zach@fantasygolfinsider.com or visit www.FantasyGolfInsider.Com