Simpson's Paradox and the Decisions of Professional Tennis Players: Examples from Grand Slam Tennis Matches

• Main Authors: CHENG, YA-WEN, 鄭雅文
• Other Authors: WU, CHIEN-WEI
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/t378kj

碩士 === 國立暨南國際大學 === 經濟學系 === 107 === The study explored why some professional tennis players easily scored more total score, but they lost the game in the end. (Statistics usually refers to the phenomenon of “Simpson's paradox” when this phenomenon occurs. We use this term below.) I hope to propose a set of rational decision factors that explain causality to these players. We collected the four grand slam tennis from 2015 to 2018 and taking the top 1000 male and the top 889 female tennis players as observation targets. The main reason for the rationality is that the number of player's turn defeat into wins. The loser has the more player's turn defeat into wins, they think that can easily win the game even if they are behind. Therefore, if the loser has the more player's turn defeat into wins under Simpson’s paradox, it means that there is a rational decision model for professional players that explain these phenomena. Besides, we also added to the factors that may affect Simpson's paradox into the regression, including the player's ranking, age, height, and tennis court material. The conclusion is that the more players turn defeat into wins per game for male players will positively influence the rational decision-making during the game. The more times there are, the more confident they will turn defeat into wins and won't give up each ball. Therefore, the chances of Simpson's paradox increase. The grass material iv site has a negative impact. Due to the small friction of the grass material and the fast ball speed, the player will choose to save energy in the receiving and retain the physical strength to the service with a high winning rate. That is why the chances of Simpson's paradox are reduced. On the other hand, female players do not have the resume of rational factors in this paper. The decision-making factors affecting the game are only the materials of clay and slow hard ground, and they are positively affected because women generally do not hit the ball at a fast speed as males. Therefore, females have more likely to compete for multiple points in a field with slower ball speeds, resulting in increasing the chance of Simpson's paradox. This point is also conform to the interpretation of the rational decision-making model.