What we mean, exactly, by anecdotal evidence is the report of an experience by one or more persons that is not objectively documented, or an experience or outcome that occurred outside of a controlled environment. Such evidence is unreliable because it depends upon the accurate perception of the witness(es), often in a situation where the event was unexpected or unusual; it is dependent upon subjective memory, which has overwhelmingly proven to be extremely error prone and subject to a host of flaws; and it cannot account for the random vagaries of a chaotic world.
