Table 2. Fixed Effect Estimates (Top) and Variance-Covariance Estimates (Bottom) for Models of the Predictors of Learning Behavior.
| Parameter | Model 1 | Model 2 |
|---|---|---|
| Fixed effects | ||
| Intercept | 0.95**(0.08) | 0.91**(0.10) |
| Set | 0.33**(0.03) | 0.24**(0.04) |
| Trend1 | 0.23**(0.02) | 0.23**(0.02) |
| Set×Trend1 | -0.12**(0.01) | -0.12**(0.01) |
| Dropoff | -0.53**(0.07) | -0.48**(0.08) |
| Set×Dropoff | -0.01(0.06) | 0.02(0.07) |
| Dropoff×NewResponse | -0.66**(0.04) | -0.69**(0.05) |
| Set×Dropoff×NewResponse | 0.33**(0.06) | 0.39**(0.07) |
| ChangeTrend | -0.13**(0.02) | -0.15**(0.02) |
| Set×ChangeTrend | 0.07**(0.02) | 0.10**(0.02) |
| NewResponse×ChangeTrend | 0.11**(0.01) | 0.15**(0.02) |
| Set×NewResponse×ChangeTrend | -0.01(0.02) | -0.03(0.03) |
| Age (centered) | 0.01(0.01) | 0.01(0.01) |
| IQ (centered) | 0.002(0.01) | 0.01(0.01) |
| SUD | 0.13(0.18) | |
| Set×SUD | 0.28**(0.07) | |
| Trend1×SUD | 0.02(0.03) | |
| Set×Trend1×SUD | 0.01(0.02) | |
| Dropoff×SUD | -0.14(0.13) | |
| Set×Dropoff×SUD | -0.11(0.13) | |
| Dropoff×NewResponse×SUD | 0.10(0.09) | |
| Set×Dropoff×NewResponse×SUD | -0.17(0.13) | |
| ChangeTrend×SUD | 0.04(0.04) | |
| Set×ChangeTrend×SUD | -0.09*(0.04) | |
| NewResponse×ChangeTrend×SUD | -0.09*(0.03) | |
| Set×NewResponse×ChangeTrend×SUD | 0.08(0.04) | |
|
| ||
| Variance of Random Effects | ||
| Intercept | 0.40 | 0.38 |
| Trend1 | 0.01 | 0.01 |
| Changetrend | 0.01 | 0.01 |
| Dropoff | 0.16 | 0.15 |
| Correlations Between Random Effects | ||
| Trend1/intercept | 0.05 | 0.05 |
| Changetrend/intercept | -0.04 | -0.04 |
| Changetrend/trend1 | -0.01 | -0.01 |
| Dropoff/intercept | -0.14 | -0.13 |
| Dropoff/trend1 | -0.03 | -0.02 |
| Dropoff/changetrend | 0.01 | 0.01 |
| -2* log-likelihood | 23,279.02 | 23,207.43** |
Standard errors are in parentheses. Set denotes the familiar versus novel set-type variable, with novel set-type as the reference category. Trend1 indicates the slope of performance during pre-contingency change time points. Drop-off signifies the difference in performance pre- and post-contingency change. NewResponse indicates a change in the correct response as a result of devaluation. Changetrend is the variable denoting the change in post-change performance relative to pre-change performance. SUD, substance use disorder. The random parameters represent the variance and covariance estimates generated from inclusion of random effects in the model. The -2log-likelihood demonstrates the value for model fit.
*
p<0.05,
**
p<0.001.