# generation.alpha.3strains: Generation of parameters for the simulations under the... In StrainRanking: Ranking of Pathogen Strains

## Description

Generation of parameters of the Dirichlet distribution used to draw the proportions of three strains at each site given in a matrix of coordinates.

## Usage

 1 generation.alpha.3strains(x) 

## Arguments

 x [2-column matrix] Coordinates where Dirichlet parameters are drawn.

## Value

Matrix of positive numerics with three columns corresponding to the number of strains that are considered and with number of rows equal to the number of sites given in x. Each row of the matrix provides the parameters of the Dirichlet distribution used to draw the proportions of three strains at each site given in x.

## Note

At each site (x_{1,i},x_{2,i}) of x, the proportions of the three strains are defined by:

(p_i(1),p_i(2),p_i(3)) \sim Dirichlet[100\{\cos(x_{2,i})+1.5,\sin(x_{1,i})+1.5,\sin(x_{2,i})+1.5\}].

## Author(s)

Soubeyrand, S., Tollenaere, C., Haon-Lasportes, E. and Laine, A.-L.

## References

Soubeyrand S., Tollenaere C., Haon-Lasportes E. & Laine A.-L. (2014). Regression-based ranking of pathogen strains with respect to their contributions to natural epidemics. PLOS ONE 9(1): e86591.

 1 generation.alpha.3strains(expand.grid(1:10,1:10))