14. Statistical Techniques in Business & Economics (11)

11 ­ © 2004 by The McGraw­Hill Companies, Inc. All rights reserved. 11 ­ 2 When you have completed this chapter, you will be able to: 1. Explain the the difference between dependent and . independent samples. 2. Conduct a test of hypothesis and obtain a confidence . interval estimate for the difference between . two population means using independent samples two population means using matched pair sample two population proportionsCopyright © 2004 by The McGraw­Hill Companies, Inc. All rights reserved. 11 ­ 3. Hypothesis Testing . Hypothesis Testing Step 1. Step 1. State the null and alternate hypotheses. State the null and alternate hypotheses Step 2. Step 2 Select the level of significance. Select the level of significance Step 3. Step 3 Identify the test statistic. Identify the test statistic Step 4. Step 4 State the decision rule. State the decision rule Step 5. Step 5 Compute the value of the test statistic . Compute the value of the test statistic . and make a decision. and make a decision Do not reject H00. Do not reject H Reject H0 0 and accept. Reject H and accept H. © 2004 by The McGraw­Hill Companies, Inc. All rights reserved. 11 ­ 4. We wish to know whether the . We wish to know whether the . the distribution of the. the distribution . of the . differences in sample . differences in sample . means has a mean of 0. means has a mean of 0 If both samples contain . at least 30 observations . we use the z distribution . as the test © 2004 by The McGraw­Hill Companies, Inc. All rights reserved. 11 ­ 5. No assumptions about the . of the populations are required. The samples are from independent populations. The formula for computing the value of z is:.