7/27/03Copyright Ed Lipinski and Mesa Community College, All rights reserved. 1 Research Methods Summer 2009 Using Inferential Statistics

2 Agenda General Housekeeping Assignments Lesson Objective Ed’s Overview / Discussion Questions.

3 Assignments Read Chapter 15 in the Text Reporting Research Results.

4 Objective “... to review inferential statistics”

5 Ed’s Overview I.Basic Concepts II.Logic of Inferential Statistics III. Parametric Statistics IV.Nonparametric Statistics V.Special Topics.

6 I. Basic Concepts A. Inferential Statistics Defined B. Sampling Distribution C. Sampling Error D. Degrees of Freedom E. Parametric Versus Nonparametric.

7 II. Logic of Inferential Statistics A. Evaluating the Null Hypothesis B. Statistical Errors Type I Error Type II Error C. Statistical Significance Alpha (  ) Is Arbitrary Typically  =.05  = P(Type I Error) D. One-Tailed Versus Two-Tailed Tests.

8 III. Parametric Statistics A. Assumptions B. Two Samples C. The t Test t Test For Independent Samples t Test For Correlated Samples D. ANOVA The F-Ratio / Interpretation Sample Size One Way Analysis Two Way Analysis.

9 IV. Nonparametric Statistics A. Chi-Square B. The Mann-Whitney U Test C. Other Options (see B & A).

10 V.Special Topics A. Power of a Statistical Test Alpha Level Sample Size Effect Size Determining Power B. Statistical / Practical Significance C. Meaning of Significance D. Data Transformations E. Combining Data.

11 Recap I.Basic Concepts II.Logic of Inferential Statistics III. Parametric Statistics IV.Nonparametric Statistics V.Special Topics.

12 Using Inferential Statistics Questions