The World Health Organization (WHO) warns that air pollution is of great concern and impacts health in many ways. To better the situation, it’s necessary to focus on air quality. However, when ...

The data in this Pew Research Center report is drawn from a national cross-sectional survey conducted by Westat. The sampling design of the survey was an address-based sampling (ABS) approach, ...

Data collection is the process of gathering and measuring information used for research. Collecting data is one of the most important steps in the research process, and is part of all disciplines ...

The sampling frame for the American Community Survey (ACS) is based on the Master Address File (MAF), which is the Census Bureau’s inventory of known housing units, group quarters (GQ), transitory ...

Water sampling and analysis methods today are logistically complex, labor-intensive, time-consuming, and costly. Could drones, which are relatively cheap provide part of the solution? After two years ...

A simple random sample is a subset of a statistical population where each member of the population is equally likely to be ...