In his book Outliers: The Story of Success (2008), Malcolm Gladwell speculates that Canadian ice hockey players that are born early in the year have an advantage. This is because the birthdate cutoff for different levels of youth hockey leagues in Canada is January 1st, so youth hockey players who are born in January and February are slightly older than teammates born later in the year. Does this slight age advantage in the beginning lead to success later on? A 2010 study examined the birth date distribution of players in the Ontario Hockey League (OHL), a high-level and selective Canadian hockey league (ages 15€“20), for the 2008€“2009 season. The number of OHL players born during the 1st quarter (Jan€“Mar), 2nd quarter (Apr€“Jun), 3rd quarter (Jul€“Sep), and 4th quarter (Oct€“Dec) of the year is shown in Table 7.11. The overall percentage of live births in Canada (year 1989) are also provided for each quarter. Is this evidence that the birthdate distribution for OHL players differs significantly from the national proportions? State the null and alternative hypotheses, calculate the chi-square statistic, find the p-value, and state the conclusion in context. 

Table 7.11

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Qtr 2 Qtr Qtr 3 Qtr 4 Qtr 1 147 110 52 OHL players % of Canadian births 23.7% 25.9% 5.9% 24.5% 50