  In this paper, we give a frequency interpretation of negative probability, as
well as of extended probability, demonstrating that to a great extent, these
new types of probabilities, behave as conventional probabilities. Extended
probability comprises both conventional probability and negative probability.
The frequency interpretation of negative probabilities gives supportive
evidence to the axiomatic system built in (Burgin, 2009; arXiv:0912.4767) for
extended probability as it is demonstrated in this paper that frequency
probabilities satisfy all axioms of extended probability.
