[Insight-users] KappaStatisticImageToImageMetric

[Tobias Heimann]

Hi all,

Just a comment to the KappaStatisticImageToImageMetric class:

The metric implemented in that class is called the Dice coefficient 
(sometimes also referenced to as Sorensen- or Czekanowski coefficient), 
*not* Kappa statistic. The original reference is:
"Dice, Lee R.: Measures of the Amount of Ecologic Associations between 
Species. Journal of Ecology, 26, 1945."
(Though the journal is not computer science related, the term "Dice 
coefficient" is widely used for the implemented formula in segmentation 
comparison/evaluation literature).

Calculation of the Kappa requires an additional region of interest and 
is a bit more complicated.
It's described e.g. in:
"Ashburner, John und Karl J. Friston: Voxel-Based Morphometry - The 
Methods. NeuroImage, 11:805{821, 2000."

Maybe the name of the class should be changed to DiceImageToImageMetric 
to avoid confusion?

Best wishes,
Tobias

-- 
Dipl.-Inform. Med. Tobias Heimann
Deutsches Krebsforschungszentrum         (German Cancer Research Center)
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