Abstract
People usually have credibilities against speakers when communicating each other. The credibility has 2 aspects; expertness and reliability which are influenced by personal-perception such as how a listener recognize a speaker. However, no studies have been done, focusing on the relationship between credibility and effects by personal-perception. Focusing on the reliability which seems to depend on personality, the authors therefore give self personality tests, another person's personality tests based on the personal-perception and reliability tests to 69 university students. The authors set several assumptions on the relationship between reliability and personality and make discussions. As a result, the authors confirm that the reliability can be described with differences between a subject's personality and an another's one evaluated by a subject.
