Title: Empirical Determination of Baseball Eras: Multivariate Changepoint Analysis in Major League Baseball Show Chinese title

Title: 棒球时代的经验确定：美国职业棒球大联盟的多元变点分析

Abstract: We use multivariate change point analysis methods, to identify not only mean shifts but also changes in variance across a wide array of statistical time series. Our primary objective is to empirically discern distinct eras in the evolution of baseball, shedding light on significant transformations in team performance and management strategies. We leverage a rich dataset comprising baseball statistics from the late 1800s to 2020, spanning over a century of the sport's history. Results confirm previous historical research, pinpointing well-known baseball eras, such as the Dead Ball Era, Integration Era, Steroid Era, and Post-Steroid Era. Moreover, the study delves into the detection of substantial changes in team performance, effectively identifying periods of both dynasties and collapses within a team's history. The multivariate change point analysis proves to be a valuable tool for understanding the intricate dynamics of baseball's evolution. The method offers a data-driven approach to unveil structural shifts in the sport's historical landscape, providing fresh insights into the impact of rule changes, player strategies, and external factors on baseball's evolution. This not only enhances our comprehension of baseball, showing more robust identification of eras than past univariate time series work, but also showcases the broader applicability of multivariate change point analysis in the domain of sports research and beyond. Show Chinese abstract

Abstract: 我们使用多元变点分析方法，不仅识别均值的变动，还识别跨越大量统计时间序列的方差变化。 我们的主要目标是实证地辨别棒球发展中的不同阶段，揭示团队表现和管理策略的重大转变。 我们利用一个丰富的数据集，该数据集包含从19世纪晚期到2020年的棒球统计数据，涵盖了超过一个世纪的体育历史。 结果证实了先前的历史研究，指出了众所周知的棒球时代，如死球时代、融合时代、类固醇时代和后类固醇时代。 此外，这项研究深入探讨了团队表现的重大变化，有效地识别了团队历史上的王朝时期和崩溃时期。 多元变点分析被证明是理解棒球演变复杂动态的一种有价值的工具。 该方法提供了一种数据驱动的方法来揭示体育历史景观中的结构变化，为揭示规则变化、球员策略以及外部因素对棒球演变的影响提供了新的见解。 这不仅增强了我们对棒球的理解，展示了比过去单变量时间序列工作更稳健的年代识别能力，而且还展示了多元变点分析在体育研究领域乃至更广泛领域的应用价值。