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by nikhilsimha 2242 days ago
Some stats from https://www.surveysystem.com/sscalc.htm Plugged in 800,000 as pop size, and 99% as confidence level and 4 as confidence interval. The number it spits out is 1039 It is a pretty good sample size.
2 comments

This would be true if the website drew a random sample of residents of San Francisco and asked them. They didn't. Rather, they drew a census of their website. No one is doubting that the website has correctly confirmed that 90% of the SF-related searches on their website were people looking to migrate outbound (so the "sampling error" here is effectively 0, unless we choose to model the census as a sample from a meta-population, in which case the classical MOE would be +-1.7% without a finite sample adjustment);

The issue here is whether we can draw a reasonable inference from that sample to the target population (all people in San Francisco). My guess is it does not. The title is not justified by the data presented.

The claims we're able to make are narrow:

A combination of annual secular growth, advertising spend, and COVID that we cannot disentangle suggests 30% increase in move requests to this moving site in the area; Separately, the sample of people using this website are more interested than outbound moves than last year.

If we want to combine these, we have "Website Shows 90% growth in raw outbound move searches among SF visitors"

That only holds true if you assume this sample is representative of the overall population of SF.