Table 1. Decision consequences in the risk, helping and risky helping task depending on p.
Expected value (EV), social welfare and earnings change (when the decider chooses to help, Option B) across risk levels (p) in the risk and helping/risky helping task. Each row represents one decision that the decider was faced with. In the risk task, the participant had to choose between a safe option (Option A) that always led to a return of 15 MU or a risky option (Option B), that led to a different expected value (EV) and therefore different expected earnings change when choosing Option B compared to Option A (last column) depending on p. In the helping/risky helping task, Option A refers to the non-helping (helping task) and safe (risky helping task) option that led to an outcome of 15 for the decider and 0 for the receiver. The expected value of the helping/risky-helping option (Option B) changed depending on p. The ‘(expected) welfare change’ column shows the change in expected total earnings (i.e. expected earnings of decider and receiver combined) when the decider would choose Option B as opposed to Option A. The ‘decider’s (expected) earnings change’ column shows the change in (expected) earnings for the decider when they would choose Option B as opposed to Option A.
| Option A (safe / non-helping option) | Option B (helping / risky-helping option) | ||||||
|---|---|---|---|---|---|---|---|
| p | EV decider | EV receiver | EV decider | EV receiver | (expected) welfare change of option B | decider's (expected) earnings change | |
| 1 | 15 | – | 0 | – | – | -15 | |
| 0.9 | 15 | – | 2.6 | – | – | -12.4 | |
| 0.8 | 15 | – | 5.2 | – | – | -9.8 | |
| 0.7 | 15 | – | 7.8 | – | – | -7.2 | |
| 0.6 | 15 | – | 10.4 | – | – | -4.6 | |
| 0.5 | 15 | – | 13 | – | – | -2 | |
| 0.4 | 15 | – | 15.6 | – | – | 0.6 | |
| 0.3 | 15 | – | 18.2 | – | – | 3.2 | |
| 0.2 | 15 | – | 20.8 | – | – | 5.8 | |
| 0.1 | 15 | – | 23.4 | – | – | 8.4 | |
| 0 | 15 | – | 26 | – | – | 11 | |
| 1 | 15 | 0 | 0 | 0 | -15 | -15 | |
| 0.9 | 15 | 0 | 1.3 | 1.3 | -12.4 | -13.7 | |
| 0.8 | 15 | 0 | 2.6 | 2.6 | -9.8 | -12.4 | |
| 0.7 | 15 | 0 | 3.9 | 3.9 | -7.2 | -11.1 | |
| 0.6 | 15 | 0 | 5.2 | 5.2 | -4.6 | -9.8 | |
| 0.5 | 15 | 0 | 6.5 | 6.5 | -2 | -8.5 | |
| 0.4 | 15 | 0 | 7.8 | 7.8 | 0.6 | -7.2 | |
| 0.3 | 15 | 0 | 9.1 | 9.1 | 3.2 | -5.9 | |
| 0.2 | 15 | 0 | 10.4 | 10.4 | 5.8 | -4.6 | |
| 0.1 | 15 | 0 | 11.7 | 11.7 | 8.4 | -3.3 | |
| 0 | 15 | 0 | 13 | 13 | 11 | -2 | |