Jakub Mares Jan.26,1987 MF
6 Michal Held Jan. 27, 1987 DF
7 Marek Strestik Feb. 1,1987 FW
8 Jiri Valenta Feb. 14,1988 MF
9 Jan Simunek Feb. 20,1987 DF
10 Tomas Oklestek Feb. 21,1987 MF
11 Lubos Kalouda Feb. 21,1987 MF
12 Radek Petr Feb.24,1987 GK
13 Ondred Mazuch Mar. 15,1989 DF
14 Ondred Kudela Mar. 26,1987 MF
15 Marek Suchy Mar. 29,1988 DF
16 Martid Fenin Apr. 16,1987 FW
17 Tomas Pekhart May 26,1989 FW
18 Lukas Kuban Jun. 22,1987 DF
19 Tomas Cihlar Jun. 24,1987 DF
20 Tomas Frystak Aug. 18,1987 GK
21 Tomas Micola Sep. 26,1988 MF
At the national team tryouts, the Czech soccer coaches might as well have told everyone born after midsummer that they should pack their bags and go home.
Hockey and soccer are just games, of course, involving a select few. But these exact same biases also show up in areas of much more consequence, like education. Parents with a child born at the end of the calendar year often think about holding their child back before the start of kindergarten: it's hard for a five-year-old to keep up with a child born many months earlier. But most parents, one suspects, think that whatever disadvantage a younger child faces in kindergarten eventually goes away. But it doesn't. It's just like hockey. The small initial advantage that the child born in the early part of the year has over the child born at the end of the year persists. It locks children into patterns of achievement and underachievement, encouragement and discouragement, that stretch on and on for years.
Recently, two economists—Kelly Bedard and Elizabeth Dhuey—looked at the relationship between scores on what is called the Trends in International Mathematics and Science Study, or TIMSS (math and science tests given every four years to children in many countries around the world), and month of birth. They found that among fourth graders, the oldest children scored somewhere between four and twelve percentile points better than the youngest children. That, as Dhuey explains, is a "huge effect." It means that if you take two intellectually equivalent fourth graders with birthdays at opposite ends of the cutoff date, the older student could score in the eightieth percentile, while the younger one could score in the sixty-eighth percentile. That's the difference between qualifying for a gifted program and not.
"It's just like sports," Dhuey said. "We do ability grouping early on in childhood. We have advanced reading groups and advanced math groups. So, early on, if we look at young kids, in kindergarten and first grade, the teachers are confusing maturity with ability. And they put the older kids in the advanced stream, where they learn better skills; and the next year, because they are in the higher groups, they do even better; and the next year, the same things happens, and they do even better again. The only country we don't see this going on is Denmark. They have a national policy where they have no ability grouping until the age of ten." Denmark waits to make selection decisions until maturity differences by age have evened out.
Dhuey and Bedard subsequently did the same analysis, only this time looking at college. What did they find? At four-year colleges in the United States—the highest stream of postsecondary education—students belonging to the relatively youngest group in their class are underrepresented by about 11.6 percent. That initial difference in maturity doesn't go away with time. It persists. And for thousands of students, that initial disadvantage is the difference between going to college—and having a real shot at the middle class—and not.3
"I mean, it's ridiculous," Dhuey says. "It's outlandish that our arbitrary choice of cutoff dates is causing these long-lasting effects, and no one seems to care about them."
5.
Think for a moment about what the story of hockey and early birthdays says about success.
It tells us that our notion that it is the best and the brightest who effortlessly rise to the top is much too simplistic. Yes, the hockey players who make it to the professional level are more talented than you or me. But they also got a big head start, an opportunity that they neither deserved nor earned. And that opportunity played a critical role in their success.
The sociologist Robert Merton famously called this phenomenon the "Matthew Effect" after the New Testament verse in the Gospel of Matthew: "For unto everyone that hath shall be given, and he shall have abundance. But from him that hath not shall be taken away even that which he hath." It is those who are successful, in other words, who are most likely