Recency Bias (Tversky & Kahneman)

Summary: Recency bias is type of cognitive bias that gives emphasis or greater importance for events that happened recently over ones that took place a long time ago. Examples may include the recent performance of stocks compared to ones from several years ago.

Originator: Amos Tversky and Daniel Kahneman [iii] in the early 1970s.

Keywords: recency bias, cognitive bias, recency effect

Recency bias is the tendency in which a person emphasizes (or overweighs) experiences that may be fresh in one’s memory, despite them not being necessarily relevant. [i] People may assume that because certain events happened recently, they are likely to happen again soon. This is a fallacy in that humans are unable to accurately predict the future.

After reading in the news about a high profile celebrity who died in a cruise ship accident, would a person want to attend a cruise? Perhaps not, even though the risk of death from a cruise ship accident is relatively low.

Examples

Some examples of recency bias may include investors choosing to invest in stocks during a bubble, leading to poor decisions; or playing certain lottery numbers again after a win, thinking this will lead to continued success. This kind of behavior is irrational in that does not acknowledge the true statistical probabilities of events occurring. Other examples may include concluding that a professional athlete is the best of all time due to recent strong performances, not accounting for past history.

Related phenomenon

A related phenomenon known as the recency effect [ii], discovered by Hermann Ebbinghaus during his experiments involving short term memory.  The recency effect argues that people tend to remember the most recently presented information the best. For instance, in a television commercial that presents a list of details about a product, the last piece of information is likely to be remembered best since it is still retained in short term memory. The last item in a list of grocery items or an entree on a menu is likely to be easier to remember than items in the middle of a list. This is also true for names and numbers.

Along with the recency effect, the primacy effect is similar — it argues that the first item in a list is also easier to remember compared to items in the middle. Learners can take both the recency and primacy effects into account and be mindful of them.

References 

[i] Summerfield, C., & Tsetsos, K. (2015). Do humans make good decisions?. Trends in cognitive sciences, 19(1), 27–34. https://doi.org/10.1016/j.tics.2014.11.005  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4286584/

[ii] Murre JM, Dros J. Replication and Analysis of Ebbinghaus’ Forgetting Curve. PLoS ONE. 2015;(10)7:e0120644.  doi:10.1371/journal.pone.0120644.

[iii] Kahneman, D., 2011. Thinking Fast and Slow. London. Penguin Books.