Consider a probabilistic model for a fault diagnosis problem. The class variable C represents

the health of a disk drive: C $=0$ means it is operating normally, and C $=1$ means it is in a

failed state. When the drive is running it continuously monitors itself using a temperature

and shock sensor$,$ and records two binary features, X and Y $.$ X $=1$ if the drive has been

subject to shock $($e$.$g$.,$ dropped$),$ and X $=0$ otherwise. Y $=1$ if the drive temperature has

ever been above $70$C$,$ and Y $=0$ otherwise.