The second-most watched single-sport tournament on the planet (after the soccer world cup) is underway in the subcontinent. The ICC cricket world cup is held once every 4 years and the latest edition is being jointly hosted by India, Sri Lanka, and Bangladesh. The original list also included Pakistan, but a militant attack on the Sri-Lankan national cricket team's bus there two years ago led to safety concerns. Fueled by the Indian economy, cricket is now a multi-billion dollar sport and the creation of a professional city-franchise based sports league in India three years ago is the latest example of this phenomenon. For some reason, cricket has always had an intimate connection with Operations Research (search for cricket in the archive). Today's post presents an overview of the potential benefits of using OR-enhanced scheduling in cricket.
The 2011 edition stretches over six weeks, and considering the fact that the number of teams who qualified for the finals is only 14, the duration of the tournament appears to be far too long, and has come in for considerable criticism. For example, the FIFA soccer world cup with more than twice the number of teams in the fray was completed in one month. There have been quite a few instances where the idling time for teams between any two games has been close to one week. Given this (and to minimize the number of boring mismatches), a recommendation for the 2015 world cup has been to reduce the number of teams from 14 to 10.
The 2011 WC format
The 2011 tournament schedule can be found here. We provide a quick overview of the format and 'constraints' here. The teams have been divided into two groups of 7. Each team in a group plays every other team in its own group. The top 4 teams from each group after the league phase enter the knock-out stage that includes 4 quarter-finals, 2 semis, and a grand finale. Each game lasts up to 8 hours, and is typically played in a day-night format, starting around 2pm and ending by 10pm. The majority of the revenue comes from TV ads. The media rights for this edition were sold for $2 Billion to ESPN. League matches involving host nations (and India in particular) garner huge ratings. Marquee match-ups are typically scheduled during weekends. Given the magnitude of revenue at stake, one can guess that even a 1% improvement to the schedule in terms of increased viewership and reduced player fatigue (thereby resulting in better match quality for fans) can add a lot of value.
A sample of hard and soft constraints
A minimum gap of two days between successive matches is a must to ensure adequate time for rest and travel. Minimizing total travel cost and idle time appears to be desirable. Host nations play their games on home turf to the extent possible. Day games (9am start) are also possible, if the morning fog/mist/dew factors are not overwhelming. On the other hand, locations with consistent dew problems at night are better suited for day matches to ensure a more fair contest. Reserve days are required for games that are washed-out due to inclement weather during the knock-out stage of the tournament, and any feasible schedule must take that into account. Of course, the OR-driven Duckworth-Lewis rules for rain-interrupted games are used to maximize the chances of getting a fair contest under the circumstances.
The Big Picture
The global cricket season is itself pretty packed and the overall schedule has come in for much criticism due to player burn out as well as overselling the game. As a cricket fan, it is pretty obvious that the status-quo is so dismal that better scheduling can maximize long-term revenue while also minimizing burn-out. Overselling is a major issue, not only because it kills the golden goose (long-term fan involvement in the game), but the number of inconsequential games being played has lead to match-fixing and spot-fixing (similar to point-shaving in basketball). The money involved in illegal betting is mind-blowing, and many suspect that it already is or could become another source of income for terrorist groups operating in the Af-Pak area. One does not expect OR to help resolve all these issues, but it can certainly be applied to some of the key ones it is well suited for, and the cascading positive effects can make a difference to the overall situation.
Potential OR Approaches
The Traveling Tournament Problem (TTP) popularized by Dr. Mike Trick at CMU appears to be a good starting point for improving the schedule for future cricket tournaments, including the world cup and the IPL, and ultimately, the global cricket season itself. Exact or heuristic approaches that combine constraint programming with MIP models appear to be well-suited to such problems given the complex and 'idiosyncratic nature' of some the scheduling constraints that tend to be imposed in cricket, as well the value added by even small scheduling improvements.
Looking Forward: The 2015 World Cup and Beyond
The next edition with be the "Anzac" world cup, hosted jointly by Australia and New Zealand. The distances between some cities that are likely to host some of the matches can be enormous (e.g. Perth and Sydney are more than 4000 miles apart) or relatively tiny (e.g. intra-NZ games, or Australian east-coast games (Melbourne-Adelaide is less than 800 miles), and the value that can be obtained by adopting optimized schedules can be significant.
I hope this post presents a reasonable high-level overview of cricket tournament schedules and motivates interested OR'ers to further investigate this problem. As a cricket tragic and OR professional, I would be happy to contribute toward any such effort.
(To be submitted as an entry to the March-2011 Informs Blog challenge: OR and Sports)