This article considers the estimation of insurers' cost-efficiency in a longitudinal context. The current practice ignores the tails of the cost distribution, where the most and least efficient insurers belong to. To address this issue, we propose a copula regression model to estimate insurers'...

The existing efficiency studies for the insurance industry rely on the time-invariant efficiency assumption, presumably because of the short duration of observation. However, temporal variation in firm efficiency could be substantial even for a short period of time. We demonstrate this point by...