PageRank Redefines Track and Field Rankings
The applications of Google’s PageRank algorithm extend beyond web search. Researchers applied the PageRank algorithm to rank professional track and field athletes. I invite you to view the research publication here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5456068/
At first, there appears to be an obvious solution to ranking professional track and field athletes. Why not simply order the athletes according to the number of races they have won in a given time period? As Clive B. Beggs and his colleagues point out, an athlete could win many races, but a victory against a more competitive field should be worth more than a victory against less-skilled competitors. A similar problem exists with a web-page ordering algorithm that simply ranks web pages according to the number of “in-links” it has. This ordering mechanism is a good start, but fails to effectively reflect relevance. Google’s page rank algorithm is exactly designed to eliminate this issue.
How does the International Association of Athletics Federations (IAAF) currently rank professional track and field athletes? Currently, athletes are awarded points to reflect both their race result, and the time or distance they achieved in their respective event. Ten points are awarded for a victory, eight for second place, six for third, four for fourth, two for fifth and one for sixth. The IAAF also uses their “IAAF Scoring Tables of Athletics” to award points according to a certain time or distance achieved. The athlete’s total score is the sum of the placing score and time/distance score. The research team argues that the current IAAF ranking metrics are not perfectly objective. They assert “As such, the IAAF system does not primarily assess ‘who beat who’, but rather, relies more on the times achieved and a series arbitrary classifications designed to reflect the quality of the competition”1.The IAAF have come up with their own standards for earning points, which, while indefinitely more comprehensive than the obvious solution, is subjective.
Beggs and his colleagues applied Google’s PageRank algorithm to the Diamond League Athletic Series—a global series of track and field competitions for the world’s best track and field athletes. They present an alternative to the fabricated, subjective and sometimes arbitrary ranking metrics currently used by the IAAF and a multitude of other athletic organizations. The study focuses on 33 men who run the 100m dash. In the formulation, the network is comprised of nodes (track and field athletes) and directed edges that extend from athlete A to athlete B when athlete A and B race each other and A beats B. Now, recall the intuition behind Google’s PageRank algorithm, as we discussed in class: PageRank assigns a score to each web page. A high score indicates higher relevance to a user’s search query. The score of a specific web page is determined by the number of web pages that link to it, as well as the relevance of those web pages themselves. Similarly, each track and field athlete is assigned a score, where a high score indicates a high rank. While certainly, the number of competitors an athlete has defeated plays a role in determining their score, so does the skill level of these competitors.
Beggs and his colleagues acknowledge the benefits of using the page rank algorithm instead of the current IAAF’s ranking system. They are careful to acknowledge that the PageRank algorithm may not perfectly align with everyone’s perception of relevant factors that impact an athlete’s rank, but they do, very convincingly in my opinion, demonstrate the usefulness of Google’s PageRank in providing an unbiased mechanism for athletic evaluation.
Citation:
1Beggs, C. B., Shepherd, S. J., Emmonds, S., & Jones, B. (2017). A novel application of PageRank and user preference algorithms for assessing the relative performance of track athletes in competition. Plos One,12(6). doi:10.1371/journal.pone.0178458