Learn how representative samples and random samples differ and why combining them minimizes sampling bias for accurate data.

Discover how to determine the ideal percentage of a population for a representative sample to ensure accurate data analysis with minimal sampling error.

Journal of the Royal Statistical Society. Series C (Applied Statistics), Vol. 42, No. 4 (1993), pp. 585-601 (17 pages) In this paper two-dimensional systematic sampling of land use is considered. Data ...

Consider a population of 70 individuals, for which you wish to estimate the mean annual income, μ. Assume that you have decided to use the following estimation procedure to make your estimate: simple ...

Several states with extensive water use databases rely upon the census approach. That is, data are collected for all water users withdrawing amounts greater than a specified threshold that varies from ...

SSRS conducted the National Public Opinion Reference Survey (NPORS) for Pew Research Center using address-based sampling and a multimode protocol. The survey was fielded from Feb. 1, 2024, to June 10, ...

Ipsos conducted the National Public Opinion Reference Survey (NPORS) for Pew Research Center using address-based sampling and a multimode protocol. The survey was fielded from May 19 to Sept. 5, 2023.

These are some questions about public opinion polling we've been asked frequently over the years. If your question isn't answered here, you can e-mail it to timespoll ...