In the scenario presented, the supervisor clearly demonstrates bias when he uttered his statements regarding the Volvo and its unreliability. To be more specific, the supervisor's heuristic or bias was the availability bias or error.
According to the Wikipedia Encyclopedia, the availability bias is described as, "The distortion of one's perceptions of reality due to the tendency to remember one alternative outcome of a situation much more easily than another." (2006) Furthermore, one's judgment about the relative frequency of an event often depends upon the availability or accessibility of objects or events in the processes of perception, memory or construction in the imagination
In the case of the supervisor, he only recalled the bad experience of his brother-in-law. He failed to take into account the experiences of the larger group of people who may have had experiences different from that of his brother-in-law.
The reaction of the supervisor also demonstrates another bias. In particular, this is the base rate neglect bias. The base rate neglect, otherwise known as the base rate fallacy, explains how humans, in making inferences about probability, often tend to ignore the background frequencies. (Garns, 1997)
In the case of the supervisor, this was clearly demonstrated because he failed to take into consideration the various reviews that were presented to him. ...