Department of Psychology, Grand Valley State University, Allendale, Michigan, United States of America.
PLoS One. 2013;8(2):e57753. doi: 10.1371/journal.pone.0057753. Epub 2013 Feb 27.
Relative age effects (RAEs) occur when those who are relatively older for their age group are more likely to succeed. RAEs occur reliably in some educational and athletic contexts, yet the causal mechanisms remain unclear. Here we provide the first direct test of one mechanism, selection bias, which can be defined as evaluators granting fewer opportunities to relatively younger individuals than is warranted by their latent ability. Because RAEs are well-established in hockey, we analyzed National Hockey League (NHL) drafts from 1980 to 2006. Compared to those born in the first quarter (i.e., January-March), those born in the third and fourth quarters were drafted more than 40 slots later than their productivity warranted, and they were roughly twice as likely to reach career benchmarks, such as 400 games played or 200 points scored. This selection bias in drafting did not decrease over time, apparently continues to occur, and reduces the playing opportunities of relatively younger players. This bias is remarkable because it is exhibited by professional decision makers evaluating adults in a context where RAEs have been widely publicized. Thus, selection bias based on relative age may be pervasive.
相对年龄效应（RAEs）是指在同一年龄组中相对年龄较大的人更有可能成功。RAEs 在一些教育和体育环境中可靠地发生，但因果机制仍不清楚。在这里，我们首次直接测试了一种机制，即选择偏差，可以将其定义为评估者给予相对年轻个体的机会少于其潜在能力所应得的机会。由于 RAEs 在曲棍球中已经得到充分证实，我们分析了 1980 年至 2006 年的国家曲棍球联盟（NHL）选秀。与那些在第一季度（即 1 月至 3 月）出生的人相比，那些在第三和第四季度出生的人被选中的时间比他们的生产力所应得的时间晚了 40 多轮，他们达到职业生涯基准的可能性大约是两倍，例如 400 场比赛或 200 分。这种选秀中的选择偏差并没有随着时间的推移而减少，显然仍在继续，并减少了相对年轻球员的比赛机会。这种偏差很显著，因为它是由专业决策者在一个 RAEs 已经广泛宣传的环境中评估成年人时表现出来的。因此，基于相对年龄的选择偏差可能很普遍。
