Blood pressure measurements are taken on a set of patients before and after they

Blood pressure measurements are taken on a set of patients before and after they receive a lumbar puncture (spinal tap). You are interested in determining if there is a difference between mean arterial blood pressure between the pre and post measures.Use the product-limit method to estimate the survival function S(t).Blood pressure measurements are taken on a set of patients before and after they receive a lumbar puncture (spinal tap). You are interested in determining if there is a difference between mean arterial blood pressure between the pre and post measures.Construct a survival curve based on the product-limit estimate.