字段描述

* radius (mean of distances from center to points on the perimeter) 
* texture (standard deviation of gray-scale values) 
* perimeter 
* area 
* smoothness (local variation in radius lengths) 
* compactness (perimeter^2 / area - 1.0) 
* concavity (severity of concave portions of the contour) 
* concave points (number of concave portions of the contour) 
* symmetry 
* fractal dimension ("coastline approximation" - 1)

Features are computed from a digitized image of a fine needle aspirate (FNA) of a breast mass. They describe characteristics of the cell nuclei present in the image. n the 3-dimensional space is that described in: [K. P. Bennett and O. L. Mangasarian: "Robust Linear Programming Discrimination of Two Linearly Inseparable Sets", Optimization Methods and Software 1, 1992, 23-34].

The mean, standard error and "worst" or largest (mean of the three largest values) of these features were computed for each image, resulting in 30 features. For instance, field 3 is Mean Radius, field 13 is Radius SE, field 23 is Worst Radius.