Sports betting pools, such as MajorWager's annual Bowl Contest, are popular for their low relative cost and large "jackpot" prizes. The importance of luck in pool contests means that even casual sports fans with limited knowledge feel that they have a reasonable shot of winning. While March Madness causes the most sports pool activity with the ever-popular "brackets" contests, weekly NFL pick 'em pools are also common.
Maximizing the chances of winning a pool involves more than just trying to make the correct picks for each game. It also pays to "go against the crowd" by incorporating strategies that will separate you from as many competing entries as possible. The goal in a pool is not necessarily to get the highest score, just to end up with more points than your opponents. If you were attempting to score the most points, your best strategy would be to pick all favorites. This results in the highest expected score, but would fail to separate you from your competitors since favorites tend to attract a disproportional amount of picks in sports pools.
Imagine a weekly NFL "pick 'em" pool, where the goal is to pick the most winning teams each week, regardless of point spread. This week's Monday Night Football game had the Panthers favored by 3 over the Bucs, giving the Panthers about a 60% chance of winning outright. If you are aiming for the highest score, you should obviously pick the Bucs. However, if you knew that 18 of the other 19 players in your pool picked the Bucs, it would make much more sense for you to pick the Panthers.
Picking the Panthers means that the 40% of the time that they win, you move ahead of 90% of your competitors. If you pick the Bucs, 60% of the time you win but move ahead of only one person, and the other 40% of the time you stay with the majority of the field anyway. If you were attempting to achieve the highest score, the Panthers would be the correct choice as they are most likely to win. But in the context of this particular contest, the Panthers are the much better choice as you can separate yourself from the contest field that is, as a whole, greatly underestimating a Panthers victory.
An article* published last year by Bryan Clair and David Letscher describes their optimal strategies for making selections in sports pools. The researchers from St. Louis University used data from online NFL weekly pick 'em pools and March Madness "brackets" to search for optimum pool pick selection strategies.
The authors discovered that even small favorites in betting pools tend to receive a large proportion of the players' picks. As an example, more than half of the games in a weekly NFL picks pool had 80% of the picks on one side. Vegas odds would only rarely make an NFL team an 80% (+400, or about a 10-point) favorite. Likewise, even with a 64-team field, a majority of March Madness brackets will have the same team (or one of two top teams) as the eventual winner.
The authors find that, for a contest involving only a single game, the rule of thumb is to bet on the favorite when the chance of them winning is higher than the percentage of people in the pool who picked them. However, as more and more games are added to the pool, the strategy becomes more complex, requiring computational power to find the best pick sets. The bottom line, however, is that the best picks are those that have the highest chance of winning while also being underrepresented in competitor's picks.
The overall strategy varies based upon the number of competitors in the pool. Conservative picks are optimal in smaller pools, while larger and larger pools call for more and more upsets to be chosen. The authors find that "pool avoidance" is most essential for extremely large pools, as random picks were able to outperform strategies which pick a lot of "pool favorites" (the most popular picks among competitors in the contest).
How can you use this information? For weekly NFL pick 'em pools or March Madness brackets, the probability of each team winning can be figured out from the Vegas odds. Fantasy sports websites like ESPN and Yahoo provide data on how many of their players have picked a given side that can be used as an estimation of how popular a given pick is in your pool. Teams that are receiving much more attention than the Vegas odds would imply might be good teams to pick against in hopes of an upset.
Applying this strategy to something like the Major Wager Bowl Contest is a bit trickier. Since this contest allows players to choose only a handful of picks from a larger number of bowl games, all competitors will not be affected by every game. This means that even if an upset you pick does come through, it won't necessarily provide separation from other players who haven't chosen that game.
However, since the picks are against a point spread, you can assume both sides are close to 50/50 (unless the contest lines are stale due to a large line move). So when choosing your selections, you may want to give added weight to teams that are unlikely to be popular contest picks. There is also a bias for many players to make selections for games on later dates, particularly the BCS Championship game. These high profile games will tend to have overall more picks on them, and so choosing the unpopular side in these games has more potential for separation from the field.
*Clair, Bryan and Letscher, David. Optimal Strategies for Sports Betting Pools, Operations Research 55 # 6, Nov-Dec 2007, pp 1163-1177. The full article, data, and a software suite utilizing the algorithms described in the paper are available at the authors' website: http://euler.slu.edu/~clair/pools/.
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