3.2. Statistical distribution of virus data

The major additional point specifically relevant to honey bee virus research (and probably other pathogens) is that virus titres follow an Exponential (~Logarithmic) distribution, rather than a Normal distribution (Fig. 2; Gauthier et al., 2007; Brunetto et al., 2009; Yañez et al., 2012; Locke et al., 2012). Also, the prevalence of very rare viruses (pathogens, parasites) may follow a Poisson distribution rather than a Binomial distribution. These differences in how the primary virus data is statistically distributed affects the design of an experiment, the determination of sample sizes (Wolfe and Carlin, 1999), surveying strategy, the analysis of pooled samples and the management of the data produced. This subject is treated in more detail in the BEEBOOK paper on statistical methods (Pirk et al., 2013).

3.2.2. Zero values