  The quantum fluctuations of fields can exhibit subtle correlations in space
and time. As the interval between a pair of measurements varies, the
correlation function can change sign, signaling a shift between correlation and
anti-correlation. A numerical simulation of the fluctuations requires a
knowledge of both the probability distribution and the correlation function.
Although there are widely used methods to generate a sequence of random numbers
which obey a given probability distribution, the imposition of a given
correlation function can be more difficult. Here we propose a simple method in
which the outcome of a given measurement determines a shift in the peak of the
probability distribution, to be used for the next measurement. We illustrate
this method for three examples of quantum field correlation functions, and show
that the resulting simulated function agree well with the original,
analytically derived function. We then discuss the application of this method
to numerical studies of the effects of correlations on the random walks of test
particles coupled to the fluctuating field.
