Complex decisions: The faster the better

When it comes to complex strategic decisions, a shorter thinking time is associated with a higher quality of decisions.

In chess, faster decisions are on average of higher quality. This is the conclusion of a study that has just been published in the scientific journal PNAS. The team of researchers, which in addition to Professor Uwe Sunde from LMU includes scientists from Erasmus University Rotterdam and UniDistance Suisse, analyzed data from professional games of chess. Their aim was to investigate how the time taken to make a complex strategic decision is related to the quality of this decision. Sunde and his colleagues believe the outcome of their research indicates that the decision time reflects the subjectively perceived difficulty of the problem, which can vary depending on the situation.

Correlation between speed and quality

As a behavioral economist, Uwe Sunde is interested in exploring how people make decisions. “Previously, most studies looking at decision time and quality have analyzed relatively simple decisions, frequently involving students in standardized lab settings,” says Sunde. “In our research, when we’re examining actual decisions outside the laboratory, we often have to rely on observations that are not strictly comparable.”

Working with his team of coauthors, the economist found an alternative way of examining complex strategic decisions: They analyzed individual moves made by players in professional chess tournaments. They measured the time the players took to make their decision and compared the result with the benchmarks set by chess engines to get an objective assessment of quality. The researchers compared decisions that a player made in different configurations on the chessboard against the same opponent. 

The importance of intuition

The results show that faster decisions are associated with higher decision-making quality – even taking account of the computational complexity of the decision, the distinctiveness of the alternative decisions and the pressure of time. “The correlation between the speed at which complex strategic decisions are made and the quality of these decisions is a priori ambiguous,” says Sunde. Taking more time to make a decision may result in a better-considered decision, but may also indicate that the question requiring an answer is perceived to be more difficult, which may be associated with a lower quality of decision.

“With this study, we’ve been able to show that, if you keep the objectively measurable difficulty of the decision constant, somebody who thinks for longer will make worse decisions,” says the researcher. A person who reflects on an issue for longer may possibly perceive the level of complexity to be subjectively higher. Conversely, a shorter decision-making time could indicate that the player has a strong intuition, so an innate sense of what the best move is. “This is what distinguishes humans from machines: Humans can often recognize what’s good or what isn’t good from the situation. But if a person doesn’t manage to grasp the situation quickly, they find it difficult to continue computing the problem rationally,” says Uwe Sunde.

The LMU researcher thinks it is possible that the result could also be applied to situations outside the game of chess in which complex decisions have to be made.