  We present a method for extrapolation of real-time dynamical correlation
functions which can improve the capability of matrix product state methods to
compute spectral functions. Unlike the widely used linear prediction method,
which ignores the origin of the data being extrapolated, our recursion methods
utilize a representation of the wavefunction in terms of an expansion of the
same wavefunction and its translations at earlier times. This recursion method
is exact for a noninteracting Fermi system. Surprisingly, the recursion method
is also more robust than linear prediction at large interaction strength. We
test this method on the Hubbard two-leg ladder and present more accurate
results for the spectral function than previous studies.
