Summary
The problem of reserving incurred but not reported claims is of great importance in
non-life insurance. Several of well-known methods are based on the run-off triangles
[1]. The drawbacks of those methods are: not working when starting the business;
slow reaction on changes in the insurance conditions; slow reaction on changes of the size of portfolio;
not possible to calculate the reserve for a single policy and segment of the
portfolio.
The idea of this paper is to show the significance of rating risk premiums
(according to limits and deductibles of the policy) and describe a premium-based IBNR
calculation method. The main random variable of this method is the reporting period,
which should be estimated separately for every line of business. |