A behavioural dynamic model of the relative age effect

Area of Science:

• Sports Science
• Developmental Psychology
• Sociology of Sport

Background:

• The relative age effect (RAE) is a well-documented phenomenon where athletes born earlier in the selection year have a performance advantage.
• In youth sports, this advantage is often amplified by increased training and playing opportunities, leading to a cycle of perceived skill superiority.

Purpose of the Study:

• To model the causal mechanisms of the RAE in Canadian youth ice hockey.
• To evaluate the effectiveness of three distinct policy interventions aimed at mitigating the RAE.

Main Methods:

• A positive feedback loop model was developed to simulate the RAE in Canadian youth hockey.
• The model was validated against the birth month distribution of Canadian National Hockey League players, achieving an R2 of 86.79%.
• Three policies were simulated: 1) additional support for age-disadvantaged children, 2) rotating league cut-off dates, and 3) a combination of both.

Main Results:

• The model successfully replicated the birth month distribution of elite Canadian hockey players, confirming the feedback loop hypothesis.
• All simulated policies demonstrated a reduction in the RAE, though with a notable delay in effect.
• The most effective policy involved combining targeted support for younger players with an annually rotating league cut-off date (January 1st to July 1st).

Conclusions:

• The RAE in youth hockey is perpetuated by a reinforcing cycle of opportunity based on initial age advantage.
• Targeted support for age-disadvantaged athletes and flexible, rotating age cut-offs are effective strategies for reducing the RAE.
• The combined policy intervention achieved a substantial 96% reduction in the RAE in the model's equilibrium state.