# 5.2.2. GLMM where the response variable is mortality

If survival of honey bees is the response
variable of interest, then each cage should contain a minimum of 30 bees so as
to provide a more robust estimate of their survival function. A typical
survival analysis then needs to be undertaken on the data, e.g*.* the non-parametric Kaplan-Meier
survival analysis for ‘censored’ data (so-called right-censored data in which
bees are sampled from the cage during the experiment) or the semi-parametric
Cox proportional hazards model (Cox model) for analysing effects of two or more
‘covariates’, or predictor variables such as *N. ceranae *or black queen cell virus (Collett, 2003; Zuur* et al.*, 2009;
Hendriksma* et al.*, 2011). Note: these models do not only allow for random
effects, if the design includes random effects then a GLMM (see section 5.2.)
could be an alternative (including some function of time is a predictor
variable in the GLMM).