Overview

The dcme package provides functions to compute data complexity measures.

Installation

dcme is under development and not yet available on CRAN. You can install the development version using the remotes package as follows:

Data Complexity Measures

The following complexity measures are currently implemented:

Simple Measures

  • num_examples: Number of Observations
  • num_features: Number of Features
  • num_features_numeric: Number of Numeric Features
  • num_features_binary: Number of Binary Features
  • num_features_categorical: Number of Categorical Features
  • num_classes: Number of Classes
  • proportion_features_numeric: Proportion of Numeric Features
  • proportion_features_binary: Proportion of Binary Features
  • proportion_features_categorical: Proportion of Categorical Features

Statistical Measures

  • sd_ratio: Geometric Mean Ratio of Standard Deviations
  • corr_abs: Mean Absolute Correlation Coefficient

Imbalance measures

  • num_examples_majority: Number of Observations in the Majority Class
  • num_examples_minority: Number of Observations in the Minority Class
  • proportion_examples_majority: Proportion of Majority Examples
  • proportion_examples_minority: Proportion of Minority Examples
  • IR: Imbalance Ratio (binary)
  • C1: Entropy of Class Proportions
  • C2: Imbalance Ratio (multiclass)

num_examples_majority, num_examples_minority, proportion_examples_majority, proportion_examples_minority, and IR are defined only for binary data sets.

Measures of Overlap of Individual Feature Values

  • F1: Fisher’s Discriminant Ratio
  • F2: Volume of Overlap Region
  • F3: Maximum Individual Feature Efficiency

Unfortunately these measures are implemented only for binary data sets.

Not implemented yet: F4 (Collective Feature Efficiency)

Measures of Separability of Classes

  • N2: Ratio of Average Intra/Inter Class 1-NN Distance
  • N3: Error Rate of 1-NN Classifier

Not implemented yet: N1 (Fraction of Borderline Points)

Measures of Geometry, Topology, and Density of Manifolds

  • N4: Nonlinearity of the 1-NN Classifier

Not implemented yet: T1 (Fraction of Hyperspheres Covering Data)

Dimensionality measures

  • T2: Average Number of Points per Dimension
  • T3: Average Number of Points per PCA Dimension
  • T4: Ratio Between PCA Dimension and Original Dimension

Network measures

Not implemented yet: Density, ClsCoef, Hubs

Linearity measures

Not implemented yet: L1 (Sum of the Error Distance by Linear Programming), L2 (Error Rate of Linear Classifier), L3 (Non-Linearity of a Linear Classifier)

References

Definitions and explanations of most functions implemented in the dcme package can be found in the following literature:

[1] Michie, D., Spiegelhalter, D. J., & Taylor, C. C. (1994). Machine learning, neural and statistical classification.

[2] Ho, T. K., & Basu, M. (2002). Complexity measures of supervised classification problems. IEEE transactions on pattern analysis and machine intelligence, 24(3), 289-300.

[3] Lorena, A. C., Garcia, L. P. F., Lehmann, J., Souto, M. C. P., Ho, T. K. (2018) How Complex is your classification problem? A survey on measuring classification complexity. arXiv:1808.03591.