Premier or International? Balancing Rewards and Draw Quality

This week, WTA players had a choice of tournaments: a Premier event in Stanford or an International in Washington. Stanford offers far more ranking points–470 to Washington’s 280 for the winner–and an even bigger difference in prize money–$120,000 to $43,000.

For the very best players, it’s an easy choice to head for the event with the biggest rewards. But further down the rankings, it’s not so clear cut. If enough top contenders gather at one tournament, there may be easier points (and dollars) for the taking elsewhere.

The pairing of Stanford and Washington provides a neat natural experiment that allows us to analyze players’ scheduling decisions. Both tournaments are in the same country and played on the same surface. The only major difference is the package of available rewards.

(Of course, for any particular player, there may be other strong reasons to choose one event or the other, such as local ties, previous success at the event, sponsorship commitments, or appearance fees. Also, some players might opt for Washington because of its closer proximity–and lack of time zone changes–to upcoming events in Montreal, Cincinnati, and New York. For the purpose of this analysis, though, we’ll have to ignore personal considerations.)

Lucie’s choice

Let’s start with an example: Lucie Safarova. The 17th-ranked Czech is the top seed in Washington. Before the draw was released, a simple ranking-based projection would’ve given her a 14% chance of winning the title, making her the favorite. Had she entered Stanford, she would’ve been the 8th seed, and a similar forecast would’ve given her a 3% chance of winning the title.

Advantage Washington? If Lucie wants prestige, a trophy, and more time on court, yes. But if she prefers ranking points and cash, she still should have gone to California.

That 14% chance of winning the Citi Open title, combined with her pre-tournament odds of reaching each preceding round, gives Safarova a weighted forecast of 87 ranking points and $11,800 in prize money. Had she opted for Stanford, her weighted expectation would be 95 ranking points and $21,170.

Safarova’s comparison is indicative of what we find with many more players in action this week. Even with a higher chance of advancing to the final rounds in Washington, the ranking point balance tilts in Stanford’s favor, and the prize money difference is even more extreme.

California cash

The contrast between the two events is much starker in terms of dollars than in points. As we’ve seen, the champion in Stanford receives almost three times as much as her fellow trophy-winner in Washington, but not even twice as many ranking points.

Because the prize-money pot is so much bigger in Stanford, every direct-entry player in the draws of both tournaments would have expected a bigger check from Stanford. The differences run from the extreme–Agnieszka Radwanska could have expected only 38% as much prize money in Washington than in Stanford–to the less outrageous–Ekaterina Makarova, the Citi Open #2 seed, can expect 67% as much cash in DC as she would have expected in Stanford.

Still, every single player with the option to enter either event could have expected a bigger paycheck had they chosen Stanford.

Ranking point decisions

When it comes to WTA ranking points, Stanford holds much less of an edge. Of the 48 direct-entry players in the two tournaments, 11 of them can expect more ranking points in Washington than in Stanford, including Makarova, whose expected points haul is 15% greater in DC than it would’ve been at Bank of the West.  Most of the players who would’ve done better in Washington would be seeded in DC but not in Stanford, giving them the likelihood of a much easier early-round draw at the east-coast event.

Still, for the majority of players, the bigger rewards in Stanford outweigh the difficulty of the competition. 37 of the 48 direct entries would be expected to earn more points in Stanford, and for 15 of them, their expected points in Washington would be less than 80% as much as the comparable number in California. Nine of those 15 are playing Washington. In fairness, a few of those players were ranked below the cut for Stanford, so they didn’t have a choice.

On average, players in action this week could expect 15% more ranking points in Stanford than in Washington, along with double the prize money.

Smart choices

Not every player is going to maximize her chances of winning money and racking up points every week. But it does seem extreme that, given the choices that players made this week, the balance between risks (crashing out early to a great player) and rewards (points and cash) seems so out of whack.

It may be that secondary concerns, like proximity to other events, hold more importance that I am giving them credit for. It could be that, in the run-up to higher-stakes events next month, some players are interested in playing more matches. The Citi Open does offer the likelihood of that.  Also, some players commit to one event or the other before knowing much about the relative field strength–there is the possibility that players underestimated the quality of this year’s Washington draw, which has not always been so strong.

Still, it is striking to find little evidence that players made optimal choices. On average, the players who chose Stanford could expect 16% more ranking points than if they had played Washington. The players who opted for DC could have expected 14% more ranking points in Stanford–basically the same as their colleagues on the other coast.

With this much at stake, many players could’ve improved their lot simply by thinking through their options a little better. In general, if you’re likely to be seeded at one tournament and not the other, go where the seed is. If you will be seeded at both or unseeded at both, go where the higher stakes are.

For more detail on methodology, keep reading.

To establish a baseline forecast for each player, I ran a “draw-independent” projection for each tournament. This type of projection is different from my draw projections at TennisAbstract.com–these consider the strength of the field, but mimic the odds before the draw was set. It seeds the field (that is, the top-ranked player gets the #1 seed, and so on) but randomizes the rest of the competition.

Then, for every player in the Washington draw, I ran a similar forecast of the Stanford draw in which that player replaced the lowest-ranked direct entry (here, Paula Ormaechea). Then I reversed the process for Stanford players in Washington.

With forecasts for every player in both tournaments, I calculated weighted projections of ranking points and prize money based on their odds of reaching each round at each event.