This textbook offers an accessible and comprehensive introduction to statistics for all undergraduate psychology students, but particularly those in their second and third years who have already covered an initial introductory course. It covers all of the key areas in quantitative methods including sampling, significance tests, regression, and multivariate techniques and incorporates a range of exercises and problems at the end of each chapter for the student to follow.
The free CD-ROM with tutorial modules complements and enhances the exercises in the text, offers scope for distance learning, and makes both the traditional and non-traditional approaches much more accessible.
Key points of the book are: an emphasis on measurement, data summaries and graphs; a clear explanation of statistical inference using sampling distributions and confidence intervals, making significance tests much easier to understand; and help for students to understand and judge the use of particular tests in the research context beyond simple recipe following.
Chapter 4: Research Design and Probability
Research Design and Probability
Validity in Research Design
In Chapter 2, you were introduced to measurement validity, the extent to which measurement is not contaminated by error. In this chapter, we begin by focusing on ways of ascertaining whether a researcher's inferences and conclusions have validity. The question of whether an apparent effect really is due to an experimental manipulation rather than some other cause is an example of an issue in research design validity. This chapter also introduces basic concepts in statistical inference that ...