Study of the Effect of Breast Tissue Density on Detection of Masses in Mammograms

Table 2

Average number of prototypes of malignant (M) and benign (B) masses and normal tissue (N) divided into training, validation, and test sets, distributed by density value.

Average distribution of prototypes by density value in the 30-fold cross validation study
Density	Training			Validation			Test
	M	B	N	M	B	N	M	B	N	Total
1	158.2	132.9	280.0	50.8	43.0	89.3	7.0	6.0	12.7	780.0
2	402.9	349.4	720.0	129.0	111.9	232.0	18.0	15.7	32.4	2012.0
3	236.3	238.9	559.6	76.2	76.3	178.5	10.5	10.8	25.0	1412.0
4	78.9	108.3	432.9	25.5	34.8	139.7	3.6	4.8	19.4	848.0
Overall	876.3	829.5	1192.5	281.5	266.0	639.5	39.1	37.3	89.5	5052.0