Table 6.
Results from log-likelihood difference tests for free to vary model versus constrained models.
| Model | logL | df | ΔlogL | (ΔlogL)*2 | Δdf |
|---|---|---|---|---|---|
| Model: Lifetime alcohol trajectories | |||||
| Overall free to vary model | −4785.21 | 23 | — | — | |
| Intercept comparisons‡ | |||||
| C1: Passive-Silent vs. Active-Open | −4794.48 | 22 | 9.27 | 18.53*** | 1 |
| C2: Passive-Silent vs. Passive-Open | −4797.39 | 22 | 12.18 | 24.35*** | 1 |
| C3: Passive-Silent vs. Active-Silent | −4792.18 | 22 | 6.96 | 13.93*** | 1 |
| C4: Active-Silent vs. Active-Open | −4785.26 | 22 | 0.05 | 0.09 | 1 |
| Slope comparisons‡ | |||||
| C1: Active-Silent vs. Active-Open | −4788.59 | 22 | 3.38 | 6.76** | 1 |
| C2: Passive-Silent vs. Active-Open | −4788.50 | 22 | 3.29 | 6.58** | 1 |
| C3: Active-Silent vs. Passive-Open | −4786.18 | 22 | 0.97 | 1.93 | 1 |
| Model: Lifetime smoking trajectories | |||||
| Overall free to vary model | −4629.02 | 21 | — | — | |
| Intercept comparisons‡ | |||||
| C1: Passive-Silent vs. Active-Open | −4633.40 | 20 | 4.39 | 8.78** | 1 |
| C2: Passive-Silent vs. Passive-Open | −4632.51 | 20 | 3.50 | 6.99** | 1 |
| C3: Active-Silent vs. Passive-Open | −4629.85 | 20 | 0.84 | 1.68 | 1 |
| Slope comparisons‡ | |||||
| C1: Passive-Silent vs. Passive-Open | −4636.08 | 20 | 7.06 | 14.12** | 1 |
| C2: Passive-Silent vs. Active-Open | −4633.86 | 20 | 4.84 | 9.68** | 1 |
| C3: Passive-Silent vs. Active-Silent | −4630.17 | 20 | 1.16 | 2.31 | 1 |
| Model: Lifetime chewing tobacco trajectories | |||||
| Overall free to vary model | −4204.90 | 23 | — | — | |
| Intercept comparisons | |||||
| C1: Passive-Silent vs. Active-Open | −4206.40 | 22 | 1.50 | 3.01 | 1 |
| Slope comparisons | |||||
| C1: Passive-Silent vs. Passive-Open | −4206.24 | 22 | 1.35 | 2.69 | 1 |
Note.
‡
Alpha level was adjusted based on Bonferroni correction where 0.05 alpha-level is divided by the number of tests.
***
p < .001,
**
p < .01.
To avoid unnecessarily comparison tests, the largest mean difference was tested first, followed by next greatest mean difference. Whenever a test was not significant, subsequent tests were not performed.