A study of the ability of individuals to walk in a straight line ("Can We Really Walk Straight?" Amer. J. of Physical Anthro., 1992: 19-27) reported the accompanying data on cadence (strides per second) for a sample of n 5 20 randomly selected healthy men.

A normal probability plot gives substantial support to the assumption that the population distribution of cadence is approximately normal. A descriptive summary of the data from Minitab follows:

a. Calculate and interpret a 95% confidence interval for population mean cadence.
b. Calculate and interpret a 95% prediction interval for the cadence of a single individual randomly selected from this population.
c. Calculate an interval that includes at least 99% of the cadences in the population distribution using a confidence level of 95%.

Transcribed Image Text:

95 85 .92.95 .93 .861.00 .92 .85 .81 78 .93 93 1.05 .93 1.06 1.06 96 81 96 Variable N Mean Median TrMean StDev SEMean cadence 20 0.9255 0.9300 0.9261 0.0809 0.0181 Variable cadence 0.7800 1.0600 0.8525 0.9600 Min Max Q1 Q3