You are here

How Many Subjects?
Share

How Many Subjects?
Statistical Power Analysis in Research

Second Edition


March 2015 | 160 pages | SAGE Publications, Inc

With increased emphasis on helping readers understand the context in which power calculations are done, this Second Edition introduces a simple technique of statistical power analysis that allows researchers to compute approximate sample sizes and power for a wide range of research designs. Because the same technique is used with only slight modifications for different statistical tests, researchers can then easily compare the sample sizes required by different designs and tests to make cost-effective decisions in planning a study. These comparisons demonstrate important principles of design, measurement, and analysis that are rarely discussed in courses or textbooks, making this book a valuable instructional resource as well as a must-have guide for frequent reference. 

 
PREFACE
 
1. The Rules of the Game
Exploratory Studies

 
Hypothesis Formulation

 
Null Hypothesis

 
Design

 
The Statistical Test

 
Effect Sizes: Critical, True, and Estimated

 
Power

 
 
2. General Concepts
Introduction to the Power Table

 
Statistical Considerations

 
 
3. The Pivotal Case: Interclass Correlation
The Intraclass Correlation Test

 
The ANOVA Approach to Intraclass Correlation Test

 
Normal Approximation to the Intraclass Theory

 
Non-Central t

 
Variance Ratios

 
Conclusion

 
 
4. Equality of Means: Z- and T-Test, Balanced ANOVA
Single-Sample Test, Variance Known: z-test

 
Single-Sample t-test

 
Two Sample t-test

 
An Exercise in Planning

 
Balanced Analysis of Variance (ANOVA)

 
 
5. Correlation Coefficients
Intraclass Correlation Coefficient

 
Product-Moment Correlation Coefficient

 
Rank Correlation Coefficients

 
You Study What You Measure!

 
 
6. Linear Regression Analysis
Simple Linear Regression

 
Experimental Design: Choosing the X-Values

 
Simple Linear Moderation Example

 
Problems: Collinearity and Interactions

 
Multiple Linear Regression

 
 
7. Homogeneity of Variance Tests
Two Independent Samples

 
Matched Samples

 
 
8. Binomial Tests
Single-Sample Binomial Tests

 
Two-Sample Binomial Tests

 
 
9. Contingency Table Analysis
Introduction

 
The I X J x^2-test

 
An Example of a 3 X 2 Contingency Table Analysis

 
 
10. Wrap-Up

"Kraemer and Blasey provide an authoritative and readable introduction into applied statistical power analysis and its application with many common statistical procedures."

Glenn Gamst
University of La Verne

“This is a necessary text for anyone conducting research in the real world. Nowhere else will you find a better answer to the question, 'How Many Subjects?'” 

Bryan Rooney
Concordia University College of Alberta

Too advanced for the course; but on additional/further readings list.

Ms Susanne Kirchmair
Accounting , MCI Management Center Innsbruck
June 7, 2016

For instructors

Purchasing options

Please select a format:

ISBN: 9781483319544
£22.99

SAGE Research Methods is a research methods tool created to help researchers, faculty and students with their research projects. SAGE Research Methods links over 175,000 pages of SAGE’s renowned book, journal and reference content with truly advanced search and discovery tools. Researchers can explore methods concepts to help them design research projects, understand particular methods or identify a new method, conduct their research, and write up their findings. Since SAGE Research Methods focuses on methodology rather than disciplines, it can be used across the social sciences, health sciences, and more.

With SAGE Research Methods, researchers can explore their chosen method across the depth and breadth of content, expanding or refining their search as needed; read online, print, or email full-text content; utilize suggested related methods and links to related authors from SAGE Research Methods' robust library and unique features; and even share their own collections of content through Methods Lists. SAGE Research Methods contains content from over 720 books, dictionaries, encyclopedias, and handbooks, the entire “Little Green Book,” and "Little Blue Book” series, two Major Works collating a selection of journal articles, and specially commissioned videos.