Stolen car statistics
Both the Herald and Stuff are covering the AA Insurance list of most-stolen car brands. They have both made it clear what the ranking on the list actually means – -what the denominator is:
“It’s not that there are more Honda Torneos on the road than any other car,” said AA Insurance customer relations manager Amelia Macandrew. “It’s the probability of them being stolen that’s far greater than any other car we insure.” (Stuff)
and
To calculate theft incidence rates, AA Insurance measures the number of claims made for each model of car for which 20 or more claims have been made, as a percentage of the total number of policies it holds for that model. (Herald)
It wasn’t as clear in past years: credit to the reporters and to AA Insurance for the improvement.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »