age	prescription	astigmatic	tear_rate	lenses
discrete	discrete	discrete	discrete	discrete
				class
young	myope	no	reduced	?
young	myope	no	normal	?
young	myope	yes	reduced	?
young	myope	yes	normal	?
young	hypermetrope	no	reduced	?
young	hypermetrope	no	normal	?
young	hypermetrope	yes	reduced	?
young	hypermetrope	yes	normal	?
pre-presbyopic	myope	no	reduced	?
pre-presbyopic	myope	no	normal	?
pre-presbyopic	myope	yes	reduced	?
pre-presbyopic	myope	yes	normal	?
pre-presbyopic	hypermetrope	no	reduced	?
pre-presbyopic	hypermetrope	no	normal	?
pre-presbyopic	hypermetrope	yes	reduced	?
pre-presbyopic	hypermetrope	yes	normal	?
presbyopic	myope	no	reduced	?
presbyopic	myope	no	normal	?
presbyopic	myope	yes	reduced	?
presbyopic	myope	yes	normal	?
presbyopic	hypermetrope	no	reduced	?
presbyopic	hypermetrope	no	normal	?
presbyopic	hypermetrope	yes	reduced	?
presbyopic	hypermetrope	yes	normal	?
