Discrete perturbation estimates for eigenpairs of Fredholm operator-valued functions

We present perturbation estimates for eigenvalue and eigenvector approximations for a class of Fredholm operator-valued functions. Our approach is based on perturbation estimates for the generalized resolvents and the exponential convergence of the contour integration by the trapezoidal rule. We use discrete residual functions to estimate the resolvents a posteriori. Numerical experiments are also presented.