effsize-package {effsize}

Efficient Effect Size Computation

Description

This packages contains functions to compute effect sizes both based on means difference (Cohen's d and Hedges g), dominance matrices (Cliff's Delta) and stochastic superiority (Vargha-Delaney A).

The computation (especially for Cliff's Delta) is carried on with higly efficient algorithms.

Details

The main functions are:

cliff.delta.

cohen.d.

VD.A.

Change history

0.3.1

Fixed a bug in cohen.d when PAIRED=TRUE, now the PAIRED parameter has no effect, it is left just for compatibility. In a future code clean-up it may be removed

0.4

Implemented a new algorithm with improved memory and time complexity. In particular new time complexity is T = O(n1*log(n2)) vs. the previous T = O(n1*n2), and new memory complexity M = O( n1 + n2 ) vs. the previous M = O( n1 * n2). In practice now the computation becomes feasible in a "reasonable" time.

0.4.1

Code clean-up and optimization using vectorized binary partioning.

0.5

Added Vargha and Delaney A and fixed minor bugs with Cohen.d.

0.5.1

Modified the Vargha and Delaney A computation to minimize accuracy errors.

0.5.2

Fixed bug in cliff.delta.

0.5.3

Fixed bug in cohen.d.formula.

0.5.4

Fixed minor issue detected by check.

0.5.5

Changed the effsize field magnitude to a factor value.

0.6.0

Implemented paired computation and CI computation with non-central t-distributions for cohen.d.

0.6.1

Added ability to specify factor vector and data vector for 'cliff.delta' function (thanks to Joses W. Ho).

0.6.2

na.rm in cohen.d removes all incomplete pairs when paired.

0.6.3

fixed bug in cohen.d when na.rm=TRUE, minor changes in the documentation (thanks to P.Thomas)

0.6.4

Fixed a bug related to pairedcohen.d with NAs. Minor documentation changes

0.7.0

Refactored tests using testthat package. Fixed a bug in cliff.delta returning inconsistent results when the dominance matrix is returned. Fixed issue concerning CI. Fixed bug in cohen.d when using noncentral parameter for negative effect sizes.

0.7.1

Fixed minor bugs in cliff.delta and cohen.d

0.7.2

Fixed bugs in cohen.d, order of factors is now observed and CI are computed correctly

0.7.3

Fixed bugs in cohen.d, possible endless loop, cleaned code

0.7.4

Fixed bugs in cliff.delta when values are factors

0.7.5

Fixed bugs in cohen.d for paired data

0.7.6

Fixed bugs in cohen.d for CI of paired data

0.7.7

Fixed bugs in cohen.d for non-pooled SD, plus a few pull requests on documentation

0.7.8

Fixed bug in cohen.d wrong correct type check

0.7.9

Fixed tests to be compatible with upcoming R 4.0, that sets stringsAsFactors to FALSE by default

0.8.0

Added non-central CI estimation for single sample cohen.d, fixed a bug related to order of data and added a subject parameter for paired cohen.d

Author(s)

Marco Torchiano http://softeng.polito.it/torchiano/