Passive sampling techniques have emerged as indispensable tools in the monitoring of environmental pollutants. These methods involve the in situ accumulation of contaminants over extended periods, ...

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 first video in Pew Research Center’s Methods 101 series helps explain random sampling – a concept that lies at the heart of all probability-based survey research – and why it’s important. Fresh ...

From species of marmots to moles, shrews and mice, many of the world's endangered mammals are small. Genetic sampling is important for understanding how to conserve and protect their populations. But ...

Here at Pew Research Center, we are often asked about how we conduct our research. We work hard to make our methodologies transparent and understandable, but we also know that survey mode effects and ...

Revision of Chapter 14.1 of the API Manual of Petroleum Measurement Standards (MPMS) was published in June 2001. This revision is the result of 7 years of an extensive natural gas sampling methods ...

Class imbalance presents significant challenges to customer churn prediction. Many datalevel sampling solutions have been developed to deal with this issue. In this paper, we comprehensively compare ...