Framing of decisions – how we make choices

Biogen-198624 februari 2023


Speaker:

I’ll give you a choice:

What would you prefer? An option that gives you a 99% probability of survival, or an option with a 1% probability of dying?

I bet most people would choose the option that gives 99% probability of survival.

But why?

In behavioural research, it has been known for a long time that the decisions we make can be completely different depending on how the options are presented to us.

In a famous experiment Tversky and Kahneman provided participants with the scenario where the US is preparing for an outbreak of an unusual Asian disease, which is expected to kill 600 people. Two different programs are proposed to handle the outbreak and the participants are asked to choose which program they would support.(1)

Program A: 200 people are saved.

Program B: There is 1/3 probability that 600 people are saved and 2/3 probability that no one will be saved.

In this version of the experiment, 72% select program A and 28% program B.

There is nothing wrong with either answer. On the average both programs save as many lives. In program A, we know for sure that 200 people are saved. In program B, the expected outcome will also be 200 saved (add the two possible outcomes, and we will save 1/3 of 600, which is 200).

Evidently, when the basic condition is survival most people choose the safe option. Saving 200 lives.

But if we turn the description into mortality based information something interesting happens. Now the participants have to choose between:

Program C: 400 people die.

Program D: There is 1/3 probability that no one dies and 2/3 probability that 600 dies.

In this situation 78% select program D and 22% select program C.

Once again, the expected outcome of both programs are still the same, which is also the same outcome as we expected from programs A and B. All programs result in 400 deaths. This experiment is often used to demonstrate that there is a tendency for us to be less willing to risk and gamble when we are exposed to gains, in this case survival. And more risk-seeking when we are exposed to losses, in this case mortality.

The shift in our preferences due to alternative descriptions is called the Framing effect. We make our decisions depending on how the alternatives are presented to us.

But sometimes we do not want to manipulate the choice of our fellow humans. How do we do then? Well, then, it is important to carefully express all alternatives in a neutral way, and most preferably describe the alternatives so that both the good and the bad consequences are described equally. In the case of the unusual disease from Asia, for example, we can eliminate the difference between how individuals choose in A–B and C–D by presenting the outcomes using both positive and negative words.

Program E: 200 people are saved and 400 die

Program F: there is 1/3 probability that everyone is saved and 2/3 probability that 600 die

That this works has, for instance, been shown in an experiment by Kühberger.(2)

By showing all possible outcomes and presenting them equally the risk of consciously or unconsciously affecting the choice is reduced.

Both patients and doctors are affected by what words we use when we present alternatives. Presenting alternatives from both positive and negative perspectives diminishes the risk of affecting the decision in a biased direction.(3)

 

 

Referenser:
1. Tversky, A. & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science, 211(4481), 453-458.
2. Kühberger, A. (1995). The framing of decisions: A new look at old problems. Organizational Behavior and Human Decision Processes, 62(2), 230-240.
3. Perneger, T. V. & Agoritsas, T. (2011). Doctors and patients' susceptibility to framing bias: a randomized trial. Journal of general internal medicine, 26(12), 1411-7.

 

Biogen-198625 februari 2023
Senast uppdaterad: 2023-02-13