A wrapper function to rd, norm, norm_pda,
norm_pda_gpu, plba0_gpu, plba1, plba_gpu,
plba2, plba3, lnr, and cnorm models.
random(type, pmat, n, seed = NULL)a character string indicating the model type
a matrox of accumulator x parameter
number of simulations
an integer specifying if and how the random number generator should be initialized.