sPlot: a statistical tool to unfold data distributions

Abstract : The paper advocates the use of a statistical tool dedicated to the exploration of data samples populated by several sources of events. This new technique, called sPlot, is able to unfold the contributions of the different sources to the distribution of a data sample in a given variable. The sPlot tool applies in the context of a Likelihood fit which is performed on the data sample to determine the yields of the various sources.