overlapAct: Calculate overlap of activation (Maitra's adaptation of...

In NeuroStat/NeuRRoStat: A rare collection of R functions used at the NeuroStat lab (Ghent University)

Description

Function to calculate the overlap of activation of two binarized images. The formula is an adaptation of the Dice overlap, suggested by Maitra in 2010.

Usage

overlapAct(bin_map1, bin_map2)

Arguments

bin_map1	the first binarized (thresholded) map
bin_map2	the second binarized (thresholded) map

Details

The measure is the number of hits (e.g. voxels) intersecting in both images divided by the sum of the number of hits in each image minus its intersection again:

V_{a,b}/(V_a + V_b - V_{a,b})

Reference: Maitra, R. (2010). A re-defined and generalized percent-overlap-of- activation measure for studies of fMRI reproducibility and its use in identifying outlier activation maps. Neuroimage 50, 124–135.

Value

Numeric value: measure of overlap.

NeuroStat/NeuRRoStat documentation built on May 15, 2019, 1:26 p.m.