Interpreting Negative Probabilities in the Context of Double-Slit   Interferometry
  Negative probabilities emerged at intermediate steps in various attempts to predict the distributions of quantum interference. There is no consensus on their meaning yet. It has been suggested (Khrennikov, 1998) that negative probabilities require the existence of unsuspected correlations between detection events.We evaluate this claim in light of several representative experiments. In our assessment, some of its implications are in good agreement with the data. 
Ghenadie N. Mardari