  It is becoming increasingly important to understand the uncertainties of
nuclear mass model calculations and their limitations when extrapolating to
driplines. In this paper we evaluate the parameter uncertainties the
Duflo-Zuker (DZ) shell model mass formulae by fitting to the latest
experimental mass compilation AME2012 and analyze the propagation of the
uncertainties in binding energy calculations when extrapolated to driplines.
The parameter uncertainties and uncertain propagations are evaluated with the
help of the covariance matrix thus derived. Large deviations from the
extrapolations of AME2012 are seen in superheavy nuclei. A simplified version
of the DZ model (DZ19) with much smaller uncertainties than that of DZ33 is
proposed. Calculations are compared with results from other mass formulae.
Systematics on the uncertainty propagation as well as the positions of the
driplines are also presented. The DZ mass formulae are shown to be well defined
with good extrapolation properties and rather small uncertainties, even though
some of the parameters of the full DZ33 model cannot be fully determined by
fitting to available experimental data.
