Kk. Gan et al., INCORPORATION OF THE STATISTICAL UNCERTAINTY IN THE BACKGROUND ESTIMATE INTO THE UPPER LIMIT ON THE SIGNAL, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 412(2-3), 1998, pp. 475-482
We present a procedure for calculating an upper limit on the number of
signal events which incorporates the Poisson uncertainty in the backg
round, estimated from control regions of one or two-dimensions. For a
small number of signal events, the upper limit obtained is more string
ent than that extracted without including the Poisson uncertainty. Thi
s trend continues until the number of background events is comparable
with the signal. When the number of background events is comparable or
larger than the signal, the upper limit obtained is less stringent th
an that extracted without including the Poisson uncertainty. It is the
refore important to incorporate the Poisson uncertainty into the upper
limit; otherwise the upper limit obtained could be too stringent. (C)
1998 Elsevier Science B.V. All rights reserved.