premise: A number of people are standing around a large spherical object. hypothesis: They were waiting for the tip off at a basketball game.
neutral: There are many types of spherical objects, it's a very generic phrase, therefore it cannot be assumed that the one in question is a basketball, nor that it's a basketball being used at a baseball game.  It is also illogical to infer that the people standing around the object are in fact waiting for the tip off at a basketball game.