3 Thinking Mistakes We Make When Making Decisions

1. Relying on heuristics

Researchers have found that when people have to make decisions in the face of uncertainty, they tend to use heuristics - that is, simplifications based on lightweight, efficient rules that often focus on only one aspect of the problem and ignore all others.

For example, imagine being told, "Steve is very shy and withdrawn, always comes to the rescue, is gentle and gentle, needs order and structure, and is attentive to detail." After that, you are given options for his professions: a farmer, a salesman, an airplane pilot, a librarian, a doctor. What profession do you think is the most likely?

You might want to say librarian, but there are actually many more farmers than librarians, so Steve is more likely to be a farmer, despite his personality traits. This is a representativeness heuristic.

There was an experiment in which a group of students were told about one of a hundred specialists: “Dick is married, he has no children. This is a person with great ability and high motivation, he promises to become very successful in his field. His colleagues love him."

Half of the students were told that this group of 100 people was 70% engineers and 30% lawyers, while the other half were told the other way around. Then they were asked how likely Dick could be an engineer or a lawyer, and they all replied that it was 50/50.

That is, they ignored the fact that he was much more likely to be part of a larger group: the odds should have been 70 to 30 one way or the other.

2. Ignore regression to mean

Imagine that a large group of children took two equal aptitude tests. Let's say you selected the ten best scores on the first version of the test, and then found that the same children gave the ten worst scores on the second version. And vice versa: you selected ten children with the worst scores on the first version of the test - and they also gave the best options on the second version.

This phenomenon is called "regression to the mean" and was first mentioned by Francis Galton in the 19th century. The top ten students may indeed be the best in the class, but they could have passed the test slightly better than the rest simply by luck; they are much more likely to be closer to the mean. The consequences of this phenomenon are that the top ten are likely to roll back, and the worst ten will move forward.

The researchers note that ignoring this fact can lead to dangerous consequences: “When discussing training flights, experienced instructors noted that praise for a successful landing usually leads to a less successful landing on the next attempt, while harsh criticism of a failed landing leads to a better result on next try."

The instructors concluded that verbal praise is not helpful in teaching, and verbal punishment is useful, which is contrary to accepted psychological doctrine. This conclusion is not substantiated due to the presence of regression to the mean.

3. We misjudge the probability

Researchers asked one hundred and twenty Stanford University alumni how they thought they were most likely to die.

The likelihood of dying in the United States from various causes (percentage)
Cause	Interviewed version	Real likelihood
Heart disease	22	34
Cancer	18	23
Other natural causes	33	35
All natural causes	73	92
Accident	32	5
Murder	10	1
Other unnatural reasons	11	2
All unnatural reasons	53	8

They slightly underestimated the likelihood of natural occurrences and greatly overestimated the likelihood of unnatural occurrences. They seem to have worried too much about accidents and homicides, and may not have worried enough about their health.

Will you succumb to the pressure of the majority? Why can't you tickle yourself? You will learn more about this and about the revolutionary experiments in psychology over the past hundred years in the book "All Psychology in 50 Experiments" by Adam Hart-Davis.