Description

Tendency for people to evaluate the quality of a decision based on its outcome.

Baron, J., & Hershey, J. C. (1988). Outcome bias in decision evaluation. Journal of Personality and Social Psychology, 54(4), 569–579.

Task

Participants are presented with various scenarios (e.g., a physician who decided to go ahead with an operation) and rate the quality of the decision on a 6-point scale ranging from 1 ("It was a poor decision") to 6 ("It was an excellent decision"). Eight items involve a positive outcome (e.g., "The operation succeeded") and eight items involve a negative one (e.g., "The patient died"). Different scenarios are used for the two outcome conditions.

Items (16)

Positive outcomes

1. In a penalty shootout, a team has a chance to win the final of a tournament if they score the next shot. In order to surprise the opposing goalkeeper, the coach chooses a player for this shot who usually never takes a penalty.

The player scored, his team won the final.

The coach's decision to choose this player was:

2. Laurent wants to become a municipal councilor for his small town of Yonne. As the municipal elections approached, the two running candidates (including the incumbent mayor) offered him to be on their list. After a first mandate, it is thought that the incumbent mayor will carry out a second one. Laurent is betting that the other candidate, young and dynamic, will win and chooses accordingly to join his list.

The incumbent mayor was beaten and Laurent joined the municipal council.

Laurent's decision to join the other candidate was:

3. Celine has a college exam in two days. One of her friends invited her to a party at her house tonight. Celine has decided to go, thinking she'll be studying all day tomorrow.

Celine passed her exam.

Celine's decision to go to the party at her friend's house was:

4. Paul is going on vacation. On his arrival at his destination, the tourist agency offers him a 20% reduction on his reservation (around 100 €) if he agrees to share his accommodation with another person, whom he does not know. Paul accepts.

Paul got along with his roommate and they had a great vacation together.

Paul's decision to accept a roommate was:

5. Eric went to his friend Bertrand to help him assemble a piece of furniture. At around 7:00 p.m., Bertrand told Eric that he is going to have some friends at his house tonight and offers to spend the evening with them. Eric is reluctant because he knows he tends to get bored during these evenings. He chooses to stay with his friend Bertrand.

Eric had a great evening and was not bored for a second.

Eric's decision to spend the evening with his friend Bertrand was:

6. Arthur plays roulette at the casino. He bet on the right color 5 times in a row. After a few seconds of thinking, he decides to bet all his money on the next move.

He won again and doubled his stake.

Arthur's decision to bet all his money on his last move was:

7. A group of four friends are planning to go on vacation to Cannes for a week and one of them, Thierry, is in charge of booking an apartment. He targeted two apartments, a first in the city center at 300 euros per night and a second off-center at 240 euros per night. When he submits these two possibilities to his friends, they point out to him that the photos of the second apartment cast doubt on its quality. Thierry still chooses the second apartment.

The four friends had an excellent stay in Cannes and they were fully satisfied with the apartment.

Thierry's decision to choose the second apartment was:

8. Maxime is a first-year law student and is going to take an exam session. For the constitutional law exam, two subjects are considered: "Article 16 of the Constitution" and "Cohabitation under the Fifth Republic". Maxime thinks that in the last class, clues given by the professor suggest that the exam will cover the subject on the article 16 of the Constitution. He chooses to revise only his courses on this topic.

The exam was on the article 16 of the Constitution and Maxime got an excellent grade.

Maxime's decision to revise only this topic was:

Negative outcomes

1. Julie takes a college exam at 8:00 a.m. and it is 7:50 a.m. when she leaves her house. Normally, it takes her 5 minutes to get to the university by metro or 15 minutes on foot. She was planning to take the metro, but the line she usually takes is disrupted this morning. She decides to walk to college as fast as she can.

Julie arrived late and she were not allowed to take the exam.

Julie's decision to walk to college was:

2. At the supermarket, Clara must choose a cash register to pay for her groceries. She hesitates between one with a tail of 2 people and another with a tail of 3 people. In the tail with 2 people there is an elderly person who could potentially be slow. Clara chooses the cash register with the tail of 2 people.

The senior was very slow to pay for groceries and Clara would have been much faster if she had chosen the checkout with the 3-person tail.

Clara's decision to choose the cash register with the tail of 2 people was:

3. One Friday night, Axel goes to a Japanese restaurant with some friends. Looking at the menu, he must decide between ordering his favorite dish or a new dish that looks tempting. He finally chooses the new dish.

Axel didn't like this dish and didn’t even finish it.

Axel's decision to choose the new dish over his favorite dish was:

4. Ivan is considered to be a good writer, but so far he has only published press articles. Recently, he had an original idea as the subject of a novel. If he embarks on this project and his book finds some success with the public, it would launch his career as a writer. Otherwise, he will have wasted time and will be frustrated by the failure. Ivan decides to start writing his first novel.

Ivan's novel has gone unnoticed.

Ivan's decision to start writing his first novel was:

5. Séverine is a client advisor in a bank in a small town. To get to work, she can take either a departmental road or a faster but often more congested national road. She usually takes the departmental road which allows her to drive peacefully. One morning when she is late for an appointment with a client, Séverine chooses to take the national road.

There was a traffic jam on the national road and Séverine missed her appointment.

Séverine's decision to take the national road was:

6. Two seconds before the end of a close basketball match between France and Spain where France is down 102-100, a player from the France team who entered the game at the previous time-out attempts a three-point shot.

The player missed his shot and France lost the match.

The player's decision to attempt this three-point shot was:

7. Alice needs a new washing machine. At first, she wanted to buy a model from a famous brand but found a model half the price from an unknown brand. As both models have the same warranty, the same performance, and are manufactured in the same country, she decides to buy the model from the unknown brand.

The washing machine kept breaking down.

Alice's decision to buy the cheapest washing machine was:

8. After five years together, Marie and Julien separated because they quarreled too often. After 6 months of staying in touch, they started to meet again. Marie and Julien think they have each evolved. They decided to get back together.

A year later, Marie and Julien separated again, once and for all.

Marie and Julien's decision to get back together was:

Scoring

The outcome bias score is calculated as the difference between the mean ratings of decisions with positive outcomes and the mean ratings of decisions with negative outcomes.

Sources

Berthet V. (2021). The Measurement of Individual Differences in Cognitive Biases: A Review and Improvement. Frontiers in psychology, 12, 630177.

Berthet, V., Autissier, D., & de Gardelle, V. (2022). Individual differences in decision-making: A test of a one-factor model of rationality. Personality and Individual Differences, 189, 111485.