Relative age effect in French alpine skiing: Problem and solution

Abstract

Objectives: To identify the potential bias of the relative age effect (RAE) in French 16 alpine skiers and to propose a mathematical correction adjustment for such a bias.17Methods: All performances and birthdates of skiers on the national and 18 international circuit were collected from the 2004 up to 2019. A goodness-of-fit 19 chi-square test and the residuals were used to study distribution of birth trimesters 20 in youth competitors. A linear relationship between the distribution of 21 performances and the months obtain a calibration coefficient allowing to rebalance 22 the performance by considering the effect of RAE. 23 Results: Individuals born at the beginning of the year are over-represented in the 24 elite young selections in all disciplines for both genders. A coefficient based on 25 the relationship between month of birth and performance adjusts individual 26 performance and cancels out the effect of RAE. 27 Conclusion: The RAE is present in French alpine skiing. We present a method 28 allowing to consider the effect of the RAE in the performances realized in each 29 gender and discipline. This method allows coaches to have a more objective 30 opinion on performance and to reduce selection bias.

Relative age effects in track-and-field: Identification and performance rebalancing

“…Relative age gap was defined by the time delay between athlete’s last birthday and competition date, as it can be interpreted as an index to quantify athlete’s experience within his/her age category. Using a method similar previously employed ( De Larochelambert et al, 2022 ; Difernand et al ), linear regressions for each age group between the relative age gap and the average of performances were computed in order to obtain the slope value “ c .” The slope coefficient was converted into days and used to calculate the recalibrated coefficient: r = c*d where “ c” is the slope value and “ d” the number of days until the next birthday. The recalibrated coefficient “ r ” was subtracted (in race events, measured in seconds) or added (in jumps or throws, measured in meters) to the performance in order to obtain rebalanced performances.…”

“…A recent study ( Brustio et al, 2022 ) applied corrective adjustment procedures (CAPs) as a strategy to remove relative age effects on 689 junior Italian long jumpers. A recent study on French skiers showed that it is possible to cancel out the relative age effect through recalibration ( De Larochelambert et al, 2022 ). Based on a regression coefficient per age category, performances are rebalanced according to their exact age and initial performance ( De Larochelambert et al, 2022 ).…”

“…A recent study on French skiers showed that it is possible to cancel out the relative age effect through recalibration ( De Larochelambert et al, 2022 ). Based on a regression coefficient per age category, performances are rebalanced according to their exact age and initial performance ( De Larochelambert et al, 2022 ). Using the same methods, corrective adjustment procedure were applied to more objectively monitor the performance realized by each swimmer with respect to chronological age, in all events ( Difernand et al ).…”

Potential estimation model in French alpine skiing - Individual evolution curve and progression typology

“…Like other study before ( De Larochelambert et al, 2022 ), this study aims to optimize the detection systems of French winter sports. We propose a methodology allowing to estimate the individual progress of the skiers, according to the relation between its performance and their age.…”

“…The development of all of one’s abilities does not take place at the same time for all individuals ( Katzmarzyk et al, 1997 ). As a result, selections made at an early age can generate many biases, starting with the relative age effect ( DeCouto et al, 2021 ; De Larochelambert et al, 2022 ; Roaas et al, 2022 ). A retrospective study ( Boccia et al, 2017 ) shows that only 10–25% of elite adult athletes were elite at age 16 in Italian high jump and long jump.…”