Question

Listed below are amounts​ (in millions of​ dollars) collected from parking meters by a security service company and other companies during similar time periods. Do the limited data listed here show evidence of stealing by the security service​ company's employees? Security Service Company: 1.4 1.6 1.7 1.6 1.5 1.6 1.6 1.5 1.4 1.8 Other Companies: 1.5 1.8 1.6 1.9 1.7 1.9 1.8 1.7 1.7 1.6 Find the coefficient of variation for each of the two​ samples, then compare the variation.

Answer 1

`CV=(0.1252)/(1.57)=0.07975`

`CV=(0.1317)/(1.72)=0.07657`

The relative variability is almost equal in both samples a slight greater variability can be noticed in the first sample.

Explanation:

The coefficient of variation of a sample is defined as the ratio between the mean standard deviation and the sample mean. And it represents the percentage relation of the variation of the data with respect to the average.

`CV=(S)/(\bar X)`

In the case of the first sample you have:

`CV=(0.1252)/(1.57)=0.07975`

In the case of the second sample you have:

`CV=(0.1317)/(1.72)=0.07657`

The relative variability is almost equal in both samples a slight greater variability can be noticed in the first sample.