The article Measuring and Understanding the Aging Kraft Paper on Power Transformers contained the following observations on degree of polymerization for paper specimen for which viscosity times concentration fell in a certain middle range:
418, 421, 421, 422, 425, 427, 431, 434, 437, 439, 446, 447, 448, 453, 454, 463, 465
A probability plot confirmed that the data is from normal distribution.
a) Calculate a two-sided 95% confidence interval for true average degree of polymerization. Does the interval suggest that 440 is a plausible value for true average degree of polymerization? What about 450?
b) Determine a 99% predication bound for the next observation.
c) Compare the 99% upper confidence bound for the mean with the 99% upper prediction bound for the observation.