The data aggregation problem in quantum hypothesis testing
  We discuss the implications of quantum-classical Yule-Simpson effect for quantum hypothesis testing in the presence of noise, and provide an experimental demonstration of its occurrence in the problem of discriminating which polarization quantum measurement has been actually performed by a detector box designed to measure linear polarization of single-photon states along a fixed but unknown direction. 
Simone Cialdi, Matteo G. A. Paris
quant-ph