Hastings D W, Robinson W W
Demography. 1975 Aug;12(3):455-66.
Using the 1970 1/1,000 Public Use Sample of the U.S. population, the relationships of the closed and open birth intervals with parity and mother's age, with parity and marital duration, and with children ever born/marital duration and mother's age are analyzed. These findings both replicate and expand on Srinivasan's earlier research on the open interval. The open interval is more sensitive as an index of marital fertility when marital duration and parity are controlled than when mother's age and parity are controlled.
利用1970年美国人口千分之一的公共使用样本，分析了封闭生育间隔和开放生育间隔与胎次和母亲年龄、胎次和婚姻持续时间、以及曾生育子女数/婚姻持续时间和母亲年龄之间的关系。这些发现既重复又扩展了斯里尼瓦桑早期关于开放生育间隔的研究。当控制婚姻持续时间和胎次时，开放生育间隔作为婚姻生育指标比控制母亲年龄和胎次时更敏感。
