What is the Representativeness Heuristic?

When people are not sure, they will pay attention to the similarity between one thing and another to infer the similarity between the first thing and the second thing. People assume that the future model will be similar to the past and seek a familiar model. To judge, and not to consider the cause of this pattern or the probability of repetition, that is, people tend to judge the probability of their occurrence based on whether the sample represents (or similar) the population. Cognitive psychology calls this reasoning process Representative heuristics. ^[1]

Representative heuristic (representatitiveness heuristic) When using heuristics, we must first consider the experience of the event itself or the similar events of the event, that is, the past results. This reasoning process is called representative heuristic.

In many cases, the law of representation is a very effective method that can help people quickly grasp the nature of the problem and infer the results, but sometimes it can cause serious deviations, especially the basic rate of the event (base rate neglect), that is, unconditional probability and sample size.

In 1973, Kahneman and Tversky conducted a famous experiment named "Tom W", which is as follows: Give the subject a description of Tom W .: "Tom W. has a high IQ but lacks real creativity. He likes Step by step, arrange everything in an orderly manner, write articles that are boring and stiff, but sometimes flash some playful puns and scientific fantasies. He loves competition, does not seem to care about the feelings of others, and he does not like Socialize with others. Although self-centered, there is also a strong sense of morality. "Then the participants estimate that Tom W. is most likely to be a student in which of the following majors: business management, engineering, education, law, books, Medicine, sociology? Imagine how you would answer if you were one of the subjects. As a result, the vast majority of participants believed that Tom W. was most likely an engineering student. I believe you don't have many answers. why? Most likely it is because Tom W. is most like an engineering student. In other words, the above description of Tom W. exactly matches the image that a science student should have in our minds (or represents the image of a science student), so we think that Tom W. is most likely to be Engineering students. This is the typical representative heuristic way of thinking. When facing uncertain events, we often make judgments or predictions based on how similar they are to past experience. To put it simply, it is to predict the possibility (of the current event) based on the similarity (of past experience). Does individual A belong to group B? If individual A has certain characteristics (similarity, representativeness) of population B, then individual A is considered to belong to population B. However, the participants completely ignored the student's base rate in each major. Even if there are as many students in the above 7 majors, the probability that any student is an engineering student is the same as the probability that he is a student in any other major, that is, 1/7. According to another group of participants' estimates of the proportion of all students in various majors, engineering students should be fewer than students in other majors, that is, less than 1/7. If this is taken into consideration, then the probability that he will take an arbitrary student (such as Tom W.) to study engineering should be very low. The error caused by ignoring the base ratio in the judgment is the so-called base rate fallacy. ^[2]

In many cases, the law of representation is a very effective method that can help people quickly grasp the nature of the problem and infer the results, but sometimes it can cause serious deviations. ^[1]

If we saw a man sneaking on the bus like a thief, we would consider him a thief and be more alert. Sometimes the similarity is indeed related to the possibility, so this judgment is correct, but sometimes it may make a wrong judgment because it ignores other relevant information. ^[2]

There is a large number rule in statistics, but research has found that people often believe in the "decimal number rule", that is, no matter how small the sample size, people always think that it can reflect the population. For example, when the coins tossed in the first five times are all positive, most people think that the coins tossed in the sixth time are more likely to be negatives, because people think that "positive, positive, positive, positive and negative" is more than "positive, positive, positive, positive and negative. "Is more general. Some investors keep holding some stocks that are deeply locked up, they think they haven't risen in two years, it's their turn. Investors' misconception that stock prices will "self-correct" is undoubtedly a very important reason to "sit back and forth". ^[3]

So the use of representative heuristics on the one hand is a shortcut for us to simplify the cognitive process in life to quickly draw conclusions. On the other hand, the conclusions obtained using this shortcut are not always correct, so we must treat cognition rationally result.