gnrivAllows the user to modify convergence parameters of Gauss Newton algorithm used in the gnriv function
gnriv.control(degree_w = 3, degree_tau = -1, method = "BFGS", ...)a list containing degree and method and any additional parameters in ....
degree of Markov process for persistent productivity. Defaults to 3.
degree of expansion for constant of integration. Defaults to the degree of first stage.
the method of optimization passed to optim. Defaults to "BFGS." See optim under 'Details' for listing of available methods.
additional optional control parameters passed to optim. See optim for available parameters.