### R Packages

#### personalized: Estimation and validation methods for subgroup identification and personalized medicine

The 'personalized' package is designed for the analysis of data where the effect of a treatment or intervention may vary for different patients. It can be used for either data from randomized controlled trials or observational studies and is not limited specifically to the analysis of medical data. It provides functions for fitting and validation of subgroup identification and personalized medicine models under the general subgroup identification framework of Chen et al. (2017).

#### oem: Orthogonalizing EM algorithm for penalized estimation

oem provides computation for various penalized regression models using the Orthogonalizing EM algorithm and is highly efficient for tall data. Penalties available include the lasso, MCP, SCAD, elastic net, group lasso, group MCP/SCAD, and more.

#### vennLasso: Variable selection for heterogeneous populations

The vennLasso package provides variable selection for high-dimensional modeling scenarios where heterogeneity is defined by several binary factors which stratify the population into multiple subpopulations. For example, vennLasso can be used in a hospital-wide risk modeling application if covariate effects in risk models differ for subpopulations of patients with different chronic conditions. Here the chronic conditions are the binary stratifying factors. The vennLasso provides computation for a variable selection method which yields variable selection patterns which adhere to the hierarchical nature of the relationships between the various subpopulations.

#### personalizedLong: Fused comparative intervention scoring/subgroup identification for long-term interventions

The personalizedLong package provides estimation of individualized intervention rules for long-term interventions and treatments. The underlying methodology of personalizedLong is intended for long-term interventions whose effects change smoothly over time and are heterogeneous effects across a population. The personalizedLong package provides an interface for the methodology proposed in Fused comparative intervention scoring for heterogeneity of longitudinal intervention effects''.

#### aftiv: Instrumental variable estimation under the semiparametric AFT model

The aftiv package provides instrumental variable estimation for time-to-event outcomes under the semiparametric accelerated failure time model.