メモ｜

"Our estimates indicate that younger students in a given grade cohort have lower cognitive and noncognitive skills. To shed light on the underlying mechanisms, we also examine children’s time use and interpersonal relationships. We find evidence of compensatory investment in cognitive skills by younger children, however, they are also more likely to have poor-quality relationships with their classmates and teachers, which may harm the long-term development of noncognitive skills. Our findings on skill formation have implications for efficiency and equity."

"Many papers have documented that relatively younger students in a given cohort perform more poorly in academic tests, playing sports, and other school activities. In addition, some studies have reported that month of birth affects long-term outcomes including university enrollment, labor earnings, and top management and political positions."

"The school year in Japan runs from April to March. Children who have their sixth birthday on or before April 2 enter the first grade of elementary school of that year, which implies that the youngest children in a given grade were born in March and the oldest in April.2."

"Strictly speaking, students born on April 1 are the youngest and those born on April 2 are the oldest. "