One possible explanation for the variability in estimates across the different nonprobability samples is the range of methods that online sample vendors employ. They differ on recruitment, weighting ...

A sample survey has many potential sources of error that generally have a systematic effect on the outcomes. Therefore, many large-scale field experiments are ...

The Public Opinion Quarterly, Vol. 82, No. 4 (Winter 2018), pp. 707-744 (38 pages) Many studies in various countries have found that telephone and internet surveys of probability samples yielded data ...

Statistics are often estimated from a sample rather than from the entire population. If the inclusion probability of the sample is unknown to the researcher, that is, a nonprobability sample, naively ...