internal function for calcAdjPP for a pair of traits
calcQ12(i, j, T1, T2, SS, tau, nsnpspermodel, kappa)
| i | model index for trait 1 |
|---|---|
| j | model index for trait 2 |
| T1 | index of trait 1 |
| T2 | index of trait 2 |
| SS | list consisting of lists of model configuration SNPs for each trait |
| tau | matrix of adjustment terms |
| nsnpspermodel | list of number of SNPs per model for each model in STR |
| kappa | single value of sharing parameter kappa |