  We present a simple method for determining the (correlated) uncertainties of
the light element abundances expected from big bang nucleosynthesis, which
avoids the need for lengthy Monte Carlo simulations. Our approach helps to
clarify the role of the different nuclear reactions contributing to a
particular elemental abundance and makes it easy to implement
energy-independent changes in the measured reaction rates. As an application,
we demonstrate how this method simplifies the statistical estimation of the
nucleon-to-photon ratio through comparison of the standard BBN predictions with
the observationally inferred abundances.
