The evidence from a theater ticketing office contains both a failed shortcut and a successful trigger. The failed shortcut is treating a public listing as enough for the result that a performance sells out; several cases had a public listing but no result, even though every successful case contained a public listing. The successful trigger is a sponsor full buyout, which always yields the result. Still, the result has more than one route, and some routes do not include a sponsor full buyout. Which one of the following gives the best interpretation of the evidence in this case involving a theater ticketing office?