The data in Table 10E.8 are molecular weight measurements made every two hours on a polymer (read down, then across from left to right).

(a) Calculate the sample autocorrelation function and provide an interpretation.
(b) Construct an individuals control chart with the standard deviation estimated using the moving range method. How would you interpret the chart? Are you comfortable with this interpretation?

TABLE 10E.8 Molecular Weight Measurements on a Polymer 2048 2039 2025 2,017 1.995 1.983 1943 1940 947 1972 2.042 1.983 1935 1948 1966 1.975 1.954 1.970 2,002 2.029 1,967 1,994 2.001 2,013 2,016 2.019 2,036 2.015 2.032 2.016 2.000 1.988 2,010 2,015 2,039 2015 2.021 2.010 2.012 2,003 2.051 2,056 2018 2.030 2.023 2,036 2019 2,019 2,016 2.010 2,000 2,009 ,990 1,986 1,947 1958 1983 2,010 2,006 2.000 2,002 2.010 1,952 1,988 2016 1,983 2.021 2.004 2018 2,015 2,032