Relationship Between the Relative Age Effect and Lengths of Professional Careers in Male Japanese Baseball Players: a Retrospective Analysis

Sports Medicine - Open

Table 2 Distribution of all players and the general population divided into quarters

	Q1 (Apr–Jun)		Q2 (Jul–Sep)		Q3 (Oct–Dec)		Q4 (Jan–Mar)		Total	X ²	p	w
	n	(%)	n	(%)	n	(%)	n	(%)	n
Baseball players	1434	34.0	1212	28.7	832	19.7	831	19.7	4218	506.53	<0.001	0.347
[Expected]	928		1003		1008		1278
General population	15,506,530	22.0	16,789,633	23.8	16,867,173	23.9	21,401,945	30.3	70,565,281

The number in the second row shows the expected number of players obtained using the chi-squared test based on the number of the general population.
n number of players, X ² chi² value, w effect size