概率抽样（probability sampling），也称随机抽样（random sampling），是指遵循随机原则进行的抽样，总体中每个个体都有一定的机会被选入样本。从理论上讲，概率抽样是最科学的抽样方法，它能保证抽取出来的样本对总体的代表性。 概率抽样分为等概率抽样（equal ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Mark Blumenthal and Natalie Jackson of Huffpost Pollster write: If you read polls in the news, you’re probably familiar with the term “margin of error.” What ...

Survey sampling and estimation methods form the cornerstone of modern statistical inference, underpinning research across the social, medical, and natural sciences. At their heart, these methods ...

The problem of estimating the variance of the ratio estimator in sampling with probability proportional to aggregate size is investigated. The form of nonnegative ...

Why do pollsters make such a big deal about probability sampling? You'd think that choosing people to interview should be easy. Take three of these, four of those, and two of the other. But it's not.