Mayo sees the process of science as one of probing a claim for errors by subjecting it to "severe" tests. Here the severity of a test (vis-a-vis a hypothesis) is the sampling probability that the hypothesis passes fails to pass the test given that the hypothesis does not, in fact, hold true. (Severity is calculated holding the data fixed and varying hypotheses.) This is a process-centred view of science: it sees good science as founded on methodologies that rarely permit false hypotheses to pass tests. Her pithy slogan for the contrast between her view and Bayesian epistemology is "well-probed versus highly probable". I expect that even she were willing to offer betting odds on the truth of a given claim, she would still deny that her betting odds have any relevance to the process of providing a warrant for asserting the claim.