Hindsight bias: memory impairment
Fischhoff´s original explanation of the hindsight bias, Immediate Assimilation Hypothesis,
states that memory for original predictions is altered by subsequent outcome
(Fischhoff, 1975). When learning
about the actual or alleged outcome, the person re-interprets the original evidence in the
light of the outcome. They are therefore inadvertently modifying what had been previously
stored in memory. Subsequent outcome knowledge is integrated immediately into the existing
knowledge structure. This results in a permanent modification of the person´s prior
representation of the event. Other variations of the memory impairment hypothesis
suggest that the origins of hindsight biases lay in the retrieval stage. The Selective
Retrieval Hypothesis maintains that known outcome serves as a retrieval cue for relevant
case material. Once an outcome has been learned, information congruent with this outcome
will become highly accessible. Incongruent information cannot be retrieved with the same
ease. The authors of the Dual Memory Traces Model
(Hell, Gigerenzer, Gauggel, Mall & Müller, 1988)
suggested an extension of Fischhoff´s model. They assume two separate memory traces for own
judgements and subsequent outcome information. The strength of hindsight biases is determined
by the relative strength of the memory traces.
Return to:
theoretical explanations
Literature:
Fischhoff (1975),
Hell, Gigerenzer, Gauggel, Mall & Müller (1988),
Morton, Hammersley & Bekerian (1985)
