| boot_se | Bootstrap Standard Errors (experimental) |
| center | Automatically grand-mean or group-mean center a fitted object |
| design_effect | Design Effect |
| hausman | Hausman Test (experimental) |
| hsb | HSB: High School and Beyond Data |
| icc | Intraclass Correlation (ICC) |
| ncv_tests | Non-constant Variance Tests at Level-1 (experimental) |
| plausible_values | Plausible Values Range / Random Effect Confidence Intervals |
| r2_cor | Pseudo R-squared: Squared correlation between predicted and observed values |
| r2_pve | Proportion of variance explained |
| reliability | Calculate reliability coefficients for random effects |
| robust_se | Robust Standard Errors |
| taucov | Tau Covariance |