... merged1.1
Reuters News Service informed in $ 2003$ ``iCad Inc., which sells medical imaging systems, agreed to buy closely held rival CADx Systems Inc. and its parent company, Qualia Computing Inc., to gain new technology. (...) The companies are working on a joint coordinated basis, they said, and the deal is expected to close in two weeks". 
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... probability4.1
Note that it would be possible to use the database of segmented masses to find a distribution of size and location of the masses. However, it is hard to justify that a mass with a specific shape or location cannot be present in a mammogram 
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... tissue5.1
Note that although in this work the database contains only two types of RoIs (masses or normal tissue) this can be extended to include other RoIs containing microcalcifications or architectural distortions. 
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... matrix5.2
One could argue that the template in the detection step could be obtained using such algorithm. However, this was not used here for computational reasons. Note that using our approach, the deformations of the template are modeled using only a vector of coefficients. Instead, with the 2DPCA approach, a vector of vectors will be necessary as each principal component will be a vector. 
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... threshold5.3
Remember that for each RoI we obtain a membership value to each class (mass or normal tissue). We obtain the ROC curve plotting this membership as a function of a threshold. A threshold of $ 0.5$ ensures that all RoIs will be classified as being either a mass or normal tissue. Hence, this is the threshold value used for computing the kappa statistic. 
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... analysis5.4
Note that a similar result is obtained using 2DPCA analysis. 
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