Load and return the Worcester Heart Attack Study dataset
The dataset has 500 samples and 14 features. The endpoint is death, which occurred for 215 patients (43.0%).
x (pandas.DataFrame) – The measurements for each patient.
y (structured array with 2 fields) – fstat: boolean indicating whether the endpoint has been reached or the event time is right censored.
lenfol: total length of follow-up (days from hospital admission date to date of last follow-up)