  The dependence of Swift's detection sensitivity on a burst's temporal and
spectral properties shapes the detected burst population. Using simplified
models of the detector hardware and the burst trigger system I find that Swift
is more sensitive to long, soft bursts than CGRO's BATSE, a reference detector
because of the large burst database it accumulated. Thus Swift has increased
sensitivity in the parameter space region into which time dilation and spectral
redshifting shift high redshift bursts.
