To assess the effects of the demographic transition, the two researchers split the sample into women born before 1870 and those born in or after it.

为了评估人口过渡的影响，这两名研究员分头对在1870年前和在这时及之后进行生产的妇女进行取样。

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The number of individuals in different demographic groups who would have provided usable information if response rates were equivalent. See sample weighting.

加权样本如果回复率相等，那么会提供有用信息的具有不同人口统计特征的个人。

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Type in your demographic information and you'll see a screen listing your free-sample options -- everything from cleaning products to Harlequin romance novels to toiletries.

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