Game of dice task (GDT)

The computerized GDT was a useful and interesting tool to measure DM under risk. With the participants sitting at the computer, they were given 1000 € as a basic fund and presented with a throwing six-sided dice (numbered: 1–6) [20]. Before the dice was thrown, participants were instructed to try to win as much money as possible during 18 throws. They must choose one from the following four given options:

Single number (N1): one-in-six chance to acquire 1000 € gain/loss;

Combination of two numbers (N2): two-in-six chance to acquire 500 € gain/loss;

Combination of three numbers (N3): three-in-six chance to acquire 200 € gain/loss;

Combination of four numbers (N4): four-in-six chance to acquire 100 € gain/loss;

The positive feedback utilization rate: positive feedback numbers (PFN) meant the number of times to choose N3 or N4 option and earn money, and positive feedback switching numbers (PFSN) meant the number of times to earn money after choosing N3 or N4, and then continue choosing N3 or N4 option. The positive feedback utilization rate was calculated by PFSN/PFN, and then turned into percentage (%).

The negative feedback utilization rate: negative feedback numbers (NFN) meant the number of times to choose N1 or N2 option and lose money, and negative feedback switching numbers (NFSN) meant the number of times to lose money after choosing N1 or N2, and then switch to choose N3 or N4 option. The negative feedback utilization rate was calculated by NFSN/NFN, and then turned into percentage (%).

It can be concluded that the higher the return, the higher the risk. N1 and N2 are considered as the high-risky decisions (high-risk options), and N3 and N4 are regarded as the low-risk decisions (low-risk options). After each throw, the feedback of the amount of money will be displayed on the screen. The net score (N3+N4) - (N1-N2) was calculated to investigate GDT performance. The total score was calculated to represent total money earned. Statistical analyses were conducted to calculate the final capital, net score, positive and negative feedback rate, the times to select each one from the four choices and the number of safe/risky decisions.