A list with training data and other details for the mixture example

`data(ESL.mixture)`

This list contains the following elements:

- x
a 200x2 matrix of predictors.

- y
a 200 vector of y values taking values 0 or 1.

- xnew
a 6831x2 matrix of prediction points, on a 69x99 grid.

- prob
a vector of 6831 probabilities - the true probabilities of a 1 at each point in

`xnew`

.- marginal
the marginal distribution of the predictors t each point in

`xnew`

.- px1
grid values for first coordinate in

`xnew`

.- px2
grid values for second coordinate in

`xnew`

.- means
a 20 x 2 matrix of means used in the generation of these data.