Table 2.
Model fit comparisons for the Mazur (1987) hyperbola and Myerson and Green (1995) hyperboloid (see text)
| AIC | Median R2 | ||||
|---|---|---|---|---|---|
| Outcome | Mazur (1987) | Myerson and Green (1995) | Mazur (1987) | Myerson and Green (1995) | |
| Non-smoker | Money | 9.11 | 7.57 | 0.96 | 0.98 |
| Alcohol | 14.92 | 15.97 | 0.52 | 0.75 | |
| Entertainment | 5.69 | 7.68 | 0.87 | 0.95 | |
| Food | 15.90 | 13.68 | 0.63 | 0.80 | |
| Smoker | Money | 15.74 | 14.32 | 0.74 | 0.82 |
| Alcohol | 17.63 | 16.43 | 0.12 | 0.54 | |
| Entertainment | 12.08 | 12.99 | 0.70 | 0.85 | |
| Food | 8.31 | 6.94 | 0.38 | 0.61 | |
Values presented in bold indicate the better fit. For median indifference points, the Akaike information criterion (AIC) results indicate that the hyperboloid provided a better fit five out of eight times. Comparisons of R2 values obtained from fitting both models to individual participant data indicate that the hyperboloid fit better in all cases than the hyperbola