  A number of papers have suggested that it is inappropriate to combine data
from different experiments when undertaking experimental tests of Bell's
inequalities. It has been suggested that a correct analysis, using a single
probability space, leads to inequalities which are not violated by experiment.
If correct, this would be contrary to the normal interpretation of such
experimental data.
  However, in this note, a generalised Clauser-Horne-Shimony-Holt (CHSH)
inequality is derived for a system of four experiments constructed on a single
probability space which combines the data from the four experiments. It is
shown that this leads to the standard CHSH inequality which is normally used to
interpret experimental data. Thus the commonly accepted conclusion that
experimental violations of Bell's inequality imply that local realistic models
are inconsistent with the predictions of quantum mechanics has not been
challenged.
