Online-Nonprobability-Study-2015.zip

Source & Vendor: Responses collected via nine separate online vendors; the variable Survey indicates vendor identity.

Weights:

Vendor-specific weights: WT_VENDOR_B, WT_VENDOR_C, WT_VENDOR_E, WT_VENDOR_F, WT_VENDOR_I.

Pew’s standardized weight: WT_ATP_STYLE, calibrated using the American Trends Panel (ATP).

In analysis, all samples except Sample I used WT_ATP_STYLE; Sample I used WT_VENDOR_I.

Privacy: ZIP code (Q55) removed; only state-level geographic variable retained.

Fieldwork Dates: February 24 – October 8, 2015.

Sample Size: N = 9,301.

Release & Report: Results were published in Pew’s May 2, 2016 report “Evaluating Online Nonprobability Surveys”.