{"parts":[{"text":"NIST Statistical Reference Datasets, univariate summary statistics, problem PiDigits: the first 5000 digits of the mathematical constant pi, one digit per observation. NIST uses this data set to test the accuracy of summary statistics calculations. Dataset d holds the 5000 observations in column y. Compute the sample mean of y and the sample standard deviation of y (denominator n \u2212 1)."}],"role":"user"}