This function is used to estimate the parameters of the SSFA model where half-normal distribution of inefficiency term is assumed.
L_hNV_rho(p, y = y, X = X, sc = sc, w = w, sigmau2_sar = sigmau2_sar)
Value of the SSFA log likelihood function.
a vector with the parameters to be estimated.
the dependent variable.
the model matrix.
specifies the form of the frontier model (-1 = cost, 1 = production).
the spatial weight matrix.
is the variance of the spatial correlated part of the inefficiency term estimated into ssfa.fit
function.
ssfa