In social psychology, the fundamental attribution error is a cognitive attribution bias in which observers underemphasize situational and environmental factors for the behavior of an actor while overemphasizing dispositional or personality factors. In other words, observers tend to overattribute the behaviors of others to their personality (e.g., he is late because he's selfish) and underattribute them to the situation or context (e.g., he is late because he got stuck in traffic). Although personality traits and predispositions are considered to be observable facts in psychology, the fundamental attribution error is an error because it misinterprets their effects.
The group attribution error is identical to the fundamental attribution error, where the bias is shown between members of different groups rather than different individuals.
The ultimate attribution error is a derivative of the fundamental attribution error and group attribution error relating to the actions of groups, with an additional layer of self-justification relating to whether the action of an individual is representative of the wider group.