Collection of package development tools.

Develop and evaluate treatment rules based on: (1) the standard indirect approach of split-regression, which fits regressions separately in both treatment groups and assigns an individual to the treatment option under which predicted outcome is more desirable; (2) the direct approach of outcome-weighted-learning proposed by Yingqi Zhao, Donglin Zeng, A. John Rush, and Michael Kosorok (2012) <doi:10.1080/01621459.2012.695674>; (3) the direct approach, which we refer to as direct-interactions, proposed by Shuai Chen, Lu Tian, Tianxi Cai, and Menggang Yu (2017) <doi:10.1111/biom.12676>. Please see the vignette for a walk-through of how to start with an observational dataset whose design is understood scientifically and end up with a treatment rule that is trustworthy statistically, along with an estimation of rule benefit in an independent sample.

A software package for using 'DEXi' models. 'DEXi' models are
  hierarchical qualitative multi-criteria decision models developed according to the method
  DEX (Decision EXpert, <https://dex.ijs.si/documentation/DEX_Method/DEX_Method.html>),
  using the program 'DEXi' (<https://kt.ijs.si/MarkoBohanec/dexi.html>) or
  'DEXiWin' (<https://dex.ijs.si/dexisuite/dexiwin.html>).
  A typical workflow with 'DEXiR' consists of:
  (1) reading a '.dxi' file, previously made using the 'DEXi' software (function read_dexi()),
  (2) making a data frame containing input values of one or more decision alternatives,
  (3) evaluating those alternatives (function evaluate()),
  (4) analyzing alternatives (selective_explanation(), plus_minus(), compare_alternatives()),
  (5) drawing charts.
  'DEXiR' is restricted to using models produced externally by the 'DEXi' software and does not
  provide functionality for creating and/or editing 'DEXi' models directly in 'R'.

A system for the management, assessment, and psychometric analysis of data from educational and psychological tests.

Classical Test and Item analysis, 
  Item Response analysis and data management for educational and psychological tests.