DR. EVANCE - Statistics

MA3110: Module 5 Chi Square and Anova

Exercise 5.1

Inferences from Two Samples

1

This exercise has the following two tasks:

Task 1: Consider the three samples listed in the table:

A B C

1 0 3

3 6 12

5 2 6

5 3

2

 Obtain the sample mean and the sample standard deviation of each of the three samples.

 Obtain total sum of squares (SST,) treatment sum of squares (SSTR,) and error sum of squares (SSE)

by using the defining formulas and verify that the one-way ANOVA identity holds.

 Obtain SST, SSTR, and SSE by using the computing formulas.

 Construct the one-way ANOVA table.

Task 2: Read the case study titled “Losses to Robbery” and answer the corresponding questions:

Losses to Robbery: The Federal Bureau of Investigation conducts surveys to obtain information on the value

of losses from various types of robberies. The results of the surveys are published in Population-at-Risk

Rates and Selected Crime Indicators. Independent simple random samples of reports for three types of

robberies—highway, gas station, and convenience store—gave the following data, in dollars, on the value of

losses.

Highway Gas Station Convenience Store

952 1298 844

996 1195 921

839 1174 880

MA3110: Module 5 Chi Square and Anova

Exercise 5.1

Inferences from Two Samples

2

Highway Gas Station Convenience Store

1088 1113 706

1024 953 602

1280 614

 What does treatment mean square (MSTR) measure?

 What does error mean square (MSE) measure?

 Suppose that you want to perform a one-way ANOVA to compare the mean losses among the three

types of robberies. What conditions are necessary? How crucial are those conditions?

Submission Requirements:

 Submit the assignment in a Microsoft Word or Excel document.

 Show detailed steps and provide appropriate rationale with your answers.

Evaluation Criteria:

 Correctly answered each question

 Included appropriate steps or rationale to determine the answer to each question