Full Idea
The basic idea of probabilistic causation is that a sufficient condition of C's being a cause of E is that C and E are actual, individual events, and the objective chance of E's occurring is greater given the occurrence of C than it would be without C.
Gist of Idea
Probabilistic causation says C is a cause of E if it increases the chances of E occurring
Source
report of D.H. Mellor (The Facts of Causation [1995]) by Michael Tooley - Causation and Supervenience 5.3
Book Reference
'The Oxford Handbook of Metaphysics', ed/tr. Loux,M /Zimmerman,D [OUP 2005], p.412
A Reaction
Mellor has to include objective 'chances' in his ontology to support his theory. As it stands this looks like a weak theory, since the event might not occur despite C happening, and some less likely event might turn out to be the actual cause.