Survey panels

A paid or incentivized survey is a type of statistical survey where the participants/members are rewarded through an incentive program, generally entry into a sweepstakes program or a small cash reward, for completing one or more surveys.

A paid survey is used to collect quantitative information about the participants' personal and economic habits set against their particular demographic.

Legitimate surveys are usually unpaid (as with a Gallup poll) or incentivized. Surveys where the respondent must pay or purchase products to join a panel are generally scams, as are sites that disappear before paying the participants. Legitimate surveys do not need credit card information from respondents.

When a research company needs respondents from a demographic they cannot reach they can easily reach out to a worldwide or specialty panel. By offering a cash incentive to respondents in return for feedback these companies are able to quickly fill quotas and collect the information being sought by the client.

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Wikipedia