Availability Heuristic

Following on from yesterdays discussion into the anchoring effect, we now investigate the world of heuristics. Heuristics (from the Greek, “find”) simply defined are mental shortcuts that allow the brain to come to a decision. Heuristics are fast in that they are a shortcut but what they make up for in speed they often lack in accuracy.

The Availability heuristic is one of the most prominent and researched heuristics and was defined by Kahneman & Tversky as the process of judging frequency by “the ease with which instances come to mind”.

So what does this look like, well………..How frequently is South Korea mentioned in the news?

As the winter Olympics are currently being held in Pyeongchang and new to non-stop coverage in relation to North Korea, we are likely to be able to think of many instances when we have heard or viewed South Korea in the news. This will then influence our estimate of how frequent South Korea is mentioned in the news.

A study I often refer to during couples counselling conducted was conducted by John Gottman and did a wonderful job of highlighting the availability heuristic. Each partner was asked to rate out of 100% how often they complete household duties such as washing the dishes, cooking dinner, cleaning etc. It was found that the couple estimates added up to over 100%. This is the availability heuristic at work. Each partner was able to easily and quickly recall the times they had completed the household duty and therefore estimated completing the duty at a higher frequency compared to their partner.

Schwarz et al (1991) further refined the availability heuristic through a study that asked people to rate their assertiveness. Participants were either asked to list 6 occasions or 12 occasions when they behaved assertively. Following the list, participants were then asked to rate how assertive they are. Surprisingly, even though the 12 group was able to list double the amount of times they behaved assertively, they rated themselves on average, less assertive than the group who recalled 6 assertive behaviours.

Shwarz et al (1991) concluded that the availability heuristic was not just concerned with the amount if instances that came to mind but also the fluency with which they come to mind. It would have bene difficult to think of 12 occasions of demonstrating assertive behaviour and therefore participants perception of their assertiveness was adversely affected due to the lack of fluency of the retrieval.

The Availability heuristic, although useful, is open to making significant errors in judgement. It is something that I continue to be mindful of as I myself have fallen into the trap of learning more about a certain disorder and then seeing that disorder with all my clients. If I didn’t take the time to consciously stop and think “Maybe because I have just been reading about this disorder that is now impacting on my judgement”, then major issues could arise. 



Kahneman, D. (2015). Thinking, fast and slow. New York: Farrar, Straus and Giroux

Schwarz, N., Bless, H., Strack, F., Klumpp, G., Rittenauer-Schatka, H., & Simons, A. (1991). Ease of retrieval as information: Another look at the availability heuristic. Journal of Personality and Social Psychology, 61(2), 195-202.