Mixed-Effects Additive Transformation Models with the R Package tramME
Bálint Tamási
Abstract
Regression models that accommodate correlated observations and potential nonlinear predictor-outcome relationships are fundamental in analyzing experimental and observational data. Unlike traditional parametric approaches, transformation models make weaker assumptions on the conditional response distribution, thus allowing for a more universal applicability to at least ordered univariate outcomes. This flexibility makes transformation models an attractive choice for modeling complex relationships in a wide range of domains. The R package tramME extends the transformation model framework with general random effect structures and penalized smooth terms to adapt to dependent data and nonlinear predictor-outcome relationships. This paper presents the statistical framework and implementation details of tramME, including its integration with other popular R packages for transformation modeling (mlt), mixed-effects (lme4) and additive models (mgcv). The package employs the efficient Template Model Builder framework (TMB) for fully parametric likelihood-based estimation and inference. Two illustrations demonstrate that tramME can readily model complex, dependent data structures under settings where the choice of the outcome distribution type is challenging.
1 citation
Evidence weight
Balanced mode · F 0.40 / M 0.15 / V 0.05 / R 0.40
| F · citation impact | 0.16 × 0.4 = 0.06 |
| M · momentum | 0.53 × 0.15 = 0.08 |
| V · venue signal | 0.50 × 0.05 = 0.03 |
| R · text relevance † | 0.50 × 0.4 = 0.20 |
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