Earthquake aftershock magnitudes. Refer to Exercise 2.29 (p. 46) and U.S. Geological Surve...

Earthquake aftershock magnitudes. Refer to Exercise 2.29 (p. 46) and U.S. Geological Survey data on aftershocks from a major California earthquake. The EARTHQUAKE file contains the magnitudes (measured on the Richter scale) of 2,929 aftershocks. Following is a MINITAB printout with descriptive statistics pertaining to magnitude:

a. Locate the range of the magnitudes of the 2,929 aftershocks.

b. Locate the variance of the magnitudes of the 2,929 aftershocks.

c. Locate the standard deviation of the magnitudes of the 2,929 aftershocks.

d. If the target of your interest is these specific 2,929 aftershocks, what symbols should you use to describe the variance and standard deviation?

MINITAB Output

Descriptive Statistics: MAGNITUDE

Exercise 2.29

Earthquake aftershock magnitudes. Seismologists use the term “aftershock” to describe the smaller earthquakes that follow a main earthquake. Following the Northridge earthquake of January 17, 1994, the Los Angeles area experienced 2,929 aftershocks in a three-week period. The magnitudes (measured on the Richter scale) of these aftershocks were recorded by the U.S. Geological Survey and are saved in the EARTHQUAKE file. A MINITAB relative frequency histogram for these magnitudes follows.

a. Estimate the percentage of the 2,929 aftershocks measuring between 1.5 and 2.5 on the Richter scale.

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b. Estimate the percentage of the 2,929 aftershocks measuring greater than 3.0 on the Richter scale.

MINITAB Output