The Study Of Base-rate Neglect Under Uncertainty

This article addresses the process that governs the use of base-rate and individuating information.Previous research has uncovered many conditions that encourage base-rate use.The present research investigates how base-rates are used when conditions are manipulated.To examine the functional form of the response to base-rate,four experiments demonstrated that,for the first and second experiments investigates how base-rates and individuating information are used when conditions are manipulated to encourage their use in the lawyer/engineer paradigm.In cases in which the base-rate information or the individuating information is lengthy and/or is presented late in the informational sequence,the tendency to use it is greater under summary base-rate informations than under redundant informations.The authors argue that these frameworks have limited ability to explain the success and flexibility of people's real-world judgments.Deviations from traditional norms of judgment,such as base-rate neglect,may then be explained in terms of a mismatch between the statistics given to people and the causal models they intuitively construct to support probabilistic reasoning. The third experiment show that when a clear mapping can be established from given statistics to the parameters of an intuitive causal model,people are more likely to use the statistics appropriately.Base-rate statistics are available for a range of events,including breast cancer,osteoporosis,and heart disease.However,few studies have provided base-rate statistics and asked how people use the statistics to assess their personal risk. The purpose of forth experiment is to understand how people use base-rate statistics and knowledge about themselves to assess the probability that an unpleasant event will happen to them.When people are asked to indicate the probability that a negative event will happen to them,they always adjust their judgments downward because they reason that they have better fortunate.The forth experiment show that when a clear causal model can be provided,people will combine the base-rate information with information about themselves.