In cooperatively breeding vertebrate species, a clear theoretical prediction about the direction of sex ratio adjustment can be made: mothers should bias the sex ratio of their offspring towards the helping sex when helpers are absent. A consistent trend in the direction predicted by theory...

In this paper it is illustrated, in a practical way, the use of three tools that permit the actuary to define tariff groups and to estimate risk premiums in the class-rating process for non-life insurance. The first is the segmentation analysis (CHAID and XAID) used firstly at 1997 by UNESPA in...

We propose a Poisson modelling approach to random effects Cox proportional hazards models. Specifically we describe methods of statistical inference for a class of random effects Cox models which accommodate a wide range of nested random effects distributions. The orthodox BLUP approach to...