The data report the patterns obtained by bouncing sonar signals at various angles and under various conditions. There are 208 patterns in all, 111 obtained by bouncing sonar signals off a metal cylinder and 97 obtained by bouncing signals off rocks. Each pattern is a set of 60 numbers (variables) taking values between 0 and 1.
data(sonar)
A data frame with 208 observations and 61 columns. The first 60 columns contain the variables. The 61st column gives the material: 1
rock, 2
metal.
R.P. Gorman and T. J. Sejnowski (1988) Analysis of hidden units in a layered network trained to classify sonar targets. Neural Networks 1: 75-89