Credibility is perceived integrity plus competence to make accurate statements on a specific subject.
Credibility causes people to assign significant confidence or value to others’ actions, including their personal claims regarding past experiences. Depending on our personality, we might assign more or less “default credibility” to the general claims of strangers. That default credibility will be heavily modified by any biases and preferences regarding “types of reporters” or by personal experience with the reporters.
Credibility is closely related to trust, although it’s a more specialized term. When we perceive positive credibility, we begin to trust someone within a specific (and often strictly limited) context. This often happens with people with whom we’ve had no personal interactions. By contrast, when we perceive negative credibility, we begin to actively distrust someone, and we disregard or contest their claims and actions.
The concept of credibility is essentially a heuristic, a practical shortcut, by which agents extend credit to descriptions of experiences or concepts.
Assigning credibility is heuristic when we’re just saving time by not inspecting information personally, and it’s also heuristic when the supposed information-- a descriptive indication, declaration or claim-- is not directly available. For instance, few people will ever run a particle accelerator, or read its results, but we may extend credibility to scientists who use them.
Another example: Americans are quite likely to believe that Indonesia exists, despite the fact that few of them travel there, because of an immensely interlaced network of consistent claims about that part of Earth.
Credibility ultimately derives most of its validity from peers who can inspect and fact-check claims. This accountability can create a limited but powerful “honesty of crowds”.
Accountability generally depends upon retroactive responsibility. For instance, most people won’t lie, nor guess wildly and irresponsibly, if they expect their claims to be thoroughly inspected and fact-checked later.
We develop trust in agents who repeatedly pass inspection and fact-checking– whether by us personally, by their peers, or even by random strangers– for a simple and fundamentally important reason: a good reputation can only be developed through significant time and effort, and can be quickly damaged or destroyed by a single incident of severe misinformation or disinformation.