Faculty of Education, Shiga University, Shiga, Japan.
Department of Education, The University of Tokyo, Tokyo, Japan.
Percept Mot Skills. 2023 Jun;130(3):984-998. doi: 10.1177/00315125231162745. Epub 2023 Mar 15.
We investigated recent trends in relative age effect (RAE) findings of top-level female soccer players in Japan, using data from the 2016 to 2020 seasons. We conducted two main analyses: (a) An examination of RAE for all registered players in the Japan Women's Soccer League (Nadeshiko League) from 2016 to 2020; and (b) an examination of RAE of newly registered players in the league from 2017 to 2020. In the first analysis, we found a significant difference between the number of players born in Q1 (April-June) versus Q4 (January-March), with the number of players born in Q1 greater and with the ratio between these groups ranging from 1.5 to 1.7. In the second analysis, we found a significant relationship between Q1 and Q4 for the 2017 season alone. However, the Q1/Q4 ratio ranged from 1.4 to 1.9, and the semester ratio of S1 (Q1 + Q2))/S2 (Q3 + Q4) ranged from 1.2 to 1.3, suggesting a birth month bias. Thus, there was a RAE in female soccer players playing recently in Japan's top-level leagues; and the size of the effect did not change significantly across recent seasons.
我们利用日本 2016 年至 2020 赛季的数据，研究了顶级女子足球运动员相对年龄效应（RAE）的最新趋势。我们进行了两项主要分析：（a）检查日本女子足球联赛（Nadeshiko 联赛）2016 年至 2020 年所有注册球员的 RAE；（b）检查 2017 年至 2020 年新注册球员的 RAE。在第一项分析中，我们发现出生在第一季度（4 月至 6 月）的球员数量与第四季度（1 月至 3 月）的球员数量之间存在显著差异，出生在第一季度的球员数量更多，这两组之间的比例在 1.5 到 1.7 之间。在第二项分析中，我们发现仅 2017 赛季存在 Q1 和 Q4 之间的显著关系。然而，Q1/Q4 的比例在 1.4 到 1.9 之间，S1（Q1+Q2）/S2（Q3+Q4）的学期比例在 1.2 到 1.3 之间，表明存在出生月份的偏差。因此，最近在日本顶级联赛中踢球的女子足球运动员中存在 RAE，而且最近几个赛季的影响大小没有明显变化。
