cross section
compound noun9 搭配平均频率: 7.4
有代表性的层面
accurately reflecting the typical characteristics of the whole group
准确反映整个群体的典型特征
…的代表层面
used to specify the larger group from which the sample is taken
用于指明样本来源的更大人群
从一个代表性群体中抽取
to be selected from a sample of a larger group
从一个更大群体的样本中被选中