Abstract
Normalized Mandel Parameter (Q) is introduced as a new measurement of photon statistics. Dependences of Mandel parameter Q and corresponding normalized Mandel parameter (Q) on photon-counting time interval are experimentally investigated for pseudo-thermal light. We demonstrate that (Q) is more appropriate than Q to measure the statistical deviation from Poisson distribution, because (Q) presents clearly both the intrinsic statistical properties and measuring effects. The advantages of (Q) in charactering nonclassical emissions are also discussed.