EXAMPLE 7.26

Software output of audio length data. Analysis of the natural log of the length values in Minitab produces the following output:

N Mean StDev SE Mean 95.0% C.I.
50 5.6315 0.6840 0.0967 (5.4371, 5.8259)

For comparison, the 95% t confidence interval for the original mean μ is found from the original data as follows:

N Mean StDev SE Mean 95.0% C.I.
50 354.1 307.9 43.6 (266.6, 441.6)