Fig 2: Bias-adjusted effective sample size.
From: Unrepresentative big surveys significantly overestimated US vaccine uptake
An estimate’s bias-adjusted effective sample size (different from the classic Kish effective sample size) is the size of a simple random sample that would have the same MSE as the observed estimate. Effective sample sizes are shown here on the log10 scale. The original sample size was n = 4,525,633 across 19 waves for Delphi–Facebook, n = 606,615 across 8 waves for Census Household Pulse and n = 11,421 across 11 waves for Axios–Ipsos. Shaded bands represent scenarios of ±5% benchmark imprecision in the CDC benchmark.
