Kahneman and Tverky, 1974

Question 1

Cognitive approach

Answer 1

-cognitive processes
-thinking and decision making
-intuitive and rational thinking
-reliability of cognitive processes
-biases in thinking and decision making (heuristics)

Question 2

Aim

Answer 2

to see if people rely on intuitive thinking (system one) more than rational thinking (system two).

Question 3

Methods

Answer 3

-95 participants were given a scenario of two hospitals in a town.
-one large hospital has 45 babies born each day. the smaller one has about 15.
-participants were reminded that the gender ratio is usually about 50/50.
-for 1 year, both hospitals recorded how many days had higher than 60% of one gender born.
-participants asked “which hospital do you think recorded more such days?” larger one, smaller. or about the same.

Question 4

Results

Answer 4

-78% got this wrong and most 56% answered “about the same” “presumably because these events are described by the same statistic and are therefore equally representative of the general population.”
-because the birth rate is 50/50 for boys/girls, most assumed the probability in this scenario would also be 50/50 (smaller one is correct).

Question 5

Conclusions

Answer 5

-participants used intuition (system one) rather than rational thinking (system two).
-system one thinking is commonly used when solving problems, even though it might lead to errors.