When I drove home from work a couple of days ago, I noticed a policeman flagging down precisely every tenth car in the other lane and directing the drivers towards a lay-by. He was in uniform, wearing hi-vis gear and his government-issued Walther, so non-compliance was clearly not an issue. The scene was completed by a large billboard, stating that this was no ordinary vehicle spot check but rather a road use survey. I badly want these guys on our team.
New (Free!) Software for Assessing Survey Bias
Worried about survey bias? We have updated our add-on (or ado) surveybias, which calculates our multinomial generalisation of the old Martin, Traugott, and Kennedy (2005) measure for survey bias. If you have any dichotomous or multinomial variable in your survey whose true distribution is known (e.g. from the census, electoral counts, or other official data),…