Online research in philosophy

The burden of this theorem, stated informally, is that when a hypothesis h is maximally independent of the evidence — that is, it goes wholly beyond the evidence —, then the probability p(h, e) increases when the evidence e is weakened; and hence, the weaker is the evidence, the greater is the probabilistic support.

Extraordinary claims require extraordinary evidence. But on uninteresting topics, surprising claims usually are surprising evidence; we rarely make claims without suffi- cient evidence. On interesting topics, however, we can have interests in exaggerating or downplaying our evidence, and our actions often deviate from our interests. In a simple model of noisy humans reporting on extraordinary evidence, we find that extraordinary claims from low noise people are extraordinary evidence, but such claims from high noise people are not; their claims are more likely unusual noise than unusual truth. When people are organized into a reporting chain, noise levels grow exponentially with chain length; long chains seem incapable of communicating extraordinary evidence.

An a priori thesis about evidence, defended by many, states that the only empirical fact that can affect the truth of an objective evidence claim of the form ‘e is evidence for h’ (or ‘e confirms h to degree r’) is the truth of e; all other considerations are a priori. By examining cases involving evidential flaws, I challange this claim and defend an empirical concept of evidence. In accordance with such a concept, whether, and the extent to which, e, if true, confirms h is an empirical, not a priori, fact.

This paper reconceptualizes the Daubert admissibility regime using the "evidence-based" metaphor. Although contemporary society is pervaded by calls for such things as medicine, policy, corrections, and crime prevention to be "evidence-based" and evidence is firmly associated with law, there has been little application of this notion in law and little recognition of the homology between evidence-based medicine and the Daubert inquiry. The paper argues that the Daubert inquiry may be conceived as a demand for "evidence about evidence," or "evidence-based evidence." It then uses the recent controversy over the admissibility of latent print (fingerprint) evidence to illustrate this notion. It shows that proponents of latent print evidence have had difficulty producing evidence about the reliability (or accuracy) of latent print evidence. Instead, trial courts have tended to find latent print admissible based on evidence that does not pertain directly to the accuracy of latent print evidence. Therefore, latent print evidence, as yet, is not "evidence-based evidence." Finally, the paper suggests that this state of affairs may explain the exclusion of latent print evidence in one recent case.

Abstract Evidence that supports a theory may be available to the scientist who constructs the theory and used as a guide to that construction, or it may only be discovered in the course of testing the theory. The central claim of this essay is that information about whether the evidence was accommodated or predicted affects the rational degree of confidence one ought to have in the theory. Only when the evidence is accommodated is there some reason to believe that the theoretical system was ?fudged? to fit the evidence in a way that weakens support. This weakening is an objective matter, but not one that can be conclusively determined by examining the contents of the theory and its logical relationship to the evidence. Consequently, there is less reason to believe a theory on the basis of that evidence when it is known that the evidence was accommodated than there would be if it was known instead that the same evidence had been predicted.

: Evidence claims depend on fallible assumptions. This paper discusses inferential robustness as a strategy for justifying evidence claims in spite of this fallibility. I argue that robustness can be understood as a means of establishing the partial security of evidence claims. An evidence claim is secure relative to an epistemic situation if it remains true in all scenarios that are epistemically possible relative to that epistemic situation.

In this note, I consider various precisifications of the slogan ‘evidence of evidence is evidence’. I provide counter-examples to each of these precisifications (assuming an epistemic probabilistic relevance notion of ‘evidential support’).

Evidence claims depend on fallible assumptions. Three strategies for making true evidence claims in spite of this fallibility are strengthening the support for those assumptions, weakening conclusions, and using multiple independent tests to produce robust evidence. Reliability itself, understood in frequentist terms, does not explain the usefulness of all three strategies; robustness, in particular, sometimes functions in a way that is not well-characterized in terms of reliability. I argue that, in addition to reliability, the security of evidence claims is of epistemic value, where an evidence claim is secure relative to an epistemic situation if it remains true in all scenarios that are epistemically possible relative to that epistemic situation.

: Evidence claims depend on fallible assumptions. Three strategies for making true evidence claims in spite of this fallibility are strengthening the support for those assumptions, weakening conclusions, and using multiple independent tests to produce robust evidence. Reliability itself, understood in frequentist terms, does not explain the usefulness of all three strategies; robustness, in particular, sometimes functions in a way that is not well-characterized in terms of reliability. I argue that, in addition to reliability, the security of evidence claims is of epistemic value, where an evidence claim is secure relative to an epistemic situation if it remains true in all scenarios that are epistemically possible relative to that epistemic situation.

Many philosophers have claimed that evidence for a theory is better when multiple independent tests yield the same result, i.e., when experimental results are robust. Little has been said about the grounds on which such a claim rests, however. The present essay presents an analysis of the evidential value of robustness that rests on the fallibility of assumptions about the reliability of testing procedures and a distinction between the strength of evidence and the security of an evidence claim. Robustness can enhance the security of an evidence claim either by providing what I call second-order evidence, or by providing back-up evidence for a hypothesis.