A few weeks ago, this site posted an article discussing the "relative age effect" (RAE) in US soccer (posted below). The RAE occurs when players born early the selection year, the oldest players trying out for a team, are much more likely to be selected over their younger counterparts. There can be almost 12 months of age difference between the youngest and oldest players within a particular age group. In the original article, data based on the US National Team pools showed a clear and consistent bias towards selection of relatively older players in all of the pools ranging from the U15 to the National Team. In short, US soccer suffers from a RAE
In response to the post, several emails were received with three major questions. The first was is the RAE in the US National Team pool a real phenomenon or just a one-year anomaly. The second was is there a RAE in other national team pools. The last was what are the long-term implications of the RAE. To address these questions, a bit more analysis was done and new data have been added.
Is this a real phenomenon? The data used in the original post is merely a snapshot of the current situation. Previous years pools may show different patterns. However, it is very difficult to argue that this year’s data are an anomaly. All of the US age group pools from U15 through U23 show a bias towards selection of older players. This also means that it is very likely that the RAE will persist for years to come. In the U15 pool, 62% of the players were born in the first quarter of the year. These players will receive higher level training and offered more developmental opportunities that the non-pool players. As such, one would expect that group to show greater improvement and will have a tremendous advantage in maintaining their position within the pool. In order to overcome RAE in this age group, nearly 60% of the players born in January, February and March would have to be replaced by players born in the latter three quarters of the year. So, the answer to the question is, yes, this does appear to be a real phenomenon that is likely to impact the US National Team for years to come.
Does the RAE occur internationally? The graph on the right shows the birth date distributions for the US National Team pool and the rosters of the teams competing in this summer’s European Championships. What is striking is that 82% of the players currently in the US National Team pool were born in the first half of the year. For the teams in EURO 2008, there is a much more even distribution of birthdates across the year with 23-27% born in each quarter. As a group, the European national teams show very little, if any, RAE. Based on this, it is clear that the US National Team pool suffers from the RAE to a much greater extent than the European national teams. However, it is important to acknowledge that other countries outside of the EURO 2008 competition may show RAE that is equal to or greater than that found in the US.
What are the long-term implications of the RAE? Steve Gerrard, standout player for Liverpool and the England National Team was born late in the selection year for his age. Early in his career, he failed to make the England U16 national team and was rejected for the FA school at Lilleshall. Michael Owen, however, six months his senior, was selected. In his autobiography, Gerrard recounts the effect that it had on his career, "The one nagging doubt in the back of my mind was that my rivals were bigger. I was really small and facing some tall, strong units in my position". Gerrard now stands an even 6-feet tall and weighs nearly 180 lbs.
Gerrard resented being passed over but felt fortunate that the Liverpool staff saw his potential. “I was lucky because even though I didn't make it to the FA school at Lilleshall, my parents and the coaches at Liverpool kept complete faith with me until I developed more physically. But it cannot be fair that many of the youngest kids in the school year are left on the sidelines.”
The key point of Gerrard’s comments is that many talented players with tremendous potential are being overlooked in favor of older, more physically developed athletes. In many sports, the window of opportunity for being “identified” is often very small. For some players, the window closes early in their careers. A survey of British children suggests that by age 13, 54% of players had given up their aspiration of playing at a higher level. It is important to note that at this age, many male players have not yet entered puberty, where gains in height and muscle mass are most rapid. Unfortunately, as these younger, equally talented players don’t make the “cut”, many move on to other activities. Thus, the RAE raises the possibility that US soccer (as well as other sports) loses out on many players with the potential to improve the state, regional and national level teams.
So, in response to the emails, the RAE effect of the US National Team does appear to be a real phenomenon, it seems less likely to occur in other countries, particularly the European nations and, finally, there are a number of unfortunate implications for the younger players in terms of their development and long-term participation.