Heuristics

The availability heuristic involves making decisions based upon your ease and speed of recall  of what you think are comparable situations or example.

The distortion occurs when your brain mistakes the ease and speed of recall  for the frequency and likelihood of the situation  occurring.

For example, I can recall visiting the US shortly after the 9/11 event and many of friends and relatives I met at a family wedding in Boston were surprised - and in some case astonished - that I was prepared to fly!

Excessive media coverage is a common cause of this happening where the media overdrive and sensationalism of a dramatic or tragic event can cause such events to become more available to your memory recall which in turn leads you to wrongly conclude that the event or situation is more common than in reality is the case.

The representativeness heuristic involves making a decision by comparing the present situation to the most representative mental prototype.

In other words we select the nearest "best fit" of a prior situation and, disregarding the inherent assumptions in that selection, we reason by analogy and make a present decision based on that past "best fit".

So for example, you may see someone dressed in a smart business suit who presents themself well, and assume that he/she is an efficient competent business person. Whereas in reality they may be a con-artist. Think of the film "The Sting" with Paul Newman and Robert Redford.

The affect heuristic involves making choices that are influenced by the your emotional state at the time of making the decision.

This is why it is never wise to make an important decision when you have been drinking alcohol, or are tired, or feeling heavily stressed.

Your emotional state can - and probably will - influence your decision-making process.

As a personal example, I am very aware that my immediate response to being asked to make a decision about something that I hadn't previously considered, my initial response will invariably be negative. So knowing this, I always defer making the decision until I have had 24-48 hours to reflect. More often than not, my considered decision will be positive.