Bomb Risk Elicitation Task (BRET)

Background

The Bomb Risk Elicitation Task (BRET) is an intuitive, quick test to measure risk attitudes. It was published by Paolo Crosetto and Antonio Filippin in 2012.

Participants choose how many boxes to collect out of a 10x10 matrix, earning money for each box that is successfully collected. The catch is that one of the boxes contains a bomb, and once that is selected all earnings are lost. Moreover, the box that hides the bomb is revealed only once participants make their choice.

Two versions of the game can be played: A static and a dynamic one. In the static version, participants choose the number of boxes to collect up front. The location of the box is selected once the participants made their choice. This procedure is easily played with paper and pencil. The dynamic version, on the other hand, is played on computerized devices that
can better visualize the box collection process for participants and thus improve people's intuitive understanding of the probabilities involved as well as the risks being taken. In the dynamic version participants have to press a Start button to start the automatic collection process. The computer automatically erases boxes in a predetermined manner from top to bottom and from left to right at a constant pace. The potential earnings are updated in real time, always accessible to the participant. Participants need to press another button to STOP the collection process at which point the location of the bomb is revealed and participants learn whether they won any money. The task is usually played as a one-trial game.

The Millisecond implementation runs the dynamic version of BRET and can be run on computers as well as touchscreen devices. The default setup runs the task with a 5x5 matrix but can be played with a 10x10 matrix as well.

Task Procedure

After one practice trial to demonstrate the procedure, participants run one test trial. They press the green START button which starts the collection process. By default, a new box gets erased every second. Once the red STOP button is pressed, the location of the bomb is revealed and participants learn whether or not they actually won the money.

What it Measures

The BRET measures risk attitudes

Psychological Domains

• Risky Decision Making: Making decisions that have risky consequences
• Impulsivity and Self-Regulation: It tracks the "stopping point"—the moment a participant's desire for more reward is outweighed by their fear of the penalty

Main Performance Metrics

• Total Number of Boxes Selected: numeric measure of risk propensity
• Risk Behavior Measure: category classification of risk seeking as 'risk averse', 'risk neutral' or 'risk seeking' depending on total number of boxes selected relative to the total number of boxes

Psychiatric Conditions

The BRET is primarily used in research and non-clinical settings. The following groups of people have shown an elevated risk propensity on the BRET.

• Older Adolescents
• High Scores on the Dark Factor of Personality

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Bomb Risk Elicitation Task (BRET).

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Crosetto, P., Filippin, A. (2013). The bomb risk elicitation task. J. Risk Uncertain. 47 (1), 31–65.

Holzmeister, & Pfurtscheller. (2016). OTree: The "bomb" risk elicitation task. Journal of Behavioral and Experimental Finance, 10, 105-108.

Crosetto, P., & Filippin, A. (2017). The Sound of Others: Surprising Evidence of Conformist Behavior. Southern Economic Journal, 83(4), 1038-1051.

Gioia, F. (2017). Peer effects on risk behaviour: The importance of group identity. Experimental Economics, 20(1), 100-129.