Using a truly accessible and reader-friendly approach, this comprehensive introduction to statistics redefines the way statistics can be taught and learned. Unlike other books that merely focus on procedures, Reid’s approach balances development of critical thinking skills with application of those skills to contemporary statistical analysis. He goes beyond simply presenting techniques by focusing on the key concepts readers need to master in order to ensure their long-term success. Indeed, this exciting new book offers the perfect foundation upon which readers can build as their studies and careers progress to more advanced forms of statistics. Keeping computational challenges to a minimum, Reid shows readers not only how to conduct a variety of commonly used statistical procedures, but also when each procedure should be utilized and how they are related. Following a review of descriptive statistics, he begins his discussion of inferential statistics with a two-chapter examination of the Chi Square test to introduce students to hypothesis testing, the importance of determining effect size, and the need for post hoc tests. When more complex procedures related to interval/ratio data are covered, students already have a solid understanding of the foundational concepts involved. Exploring challenging topics in an engaging and easy-to-follow manner, Reid builds concepts logically and supports learning through robust pedagogical tools, the use of SPSS, numerous examples, historical quotations, insightful questions, and helpful progress checks.

# Identifying Associations With Nominal and Interval or Ratio Data : The Phi Correlation, the Pearson r Correlation, and the Point Biserial Correlation

### Identifying Associations With Nominal and Interval or Ratio Data : The Phi Correlation, the Pearson r Correlation, and the Point Biserial Correlation

You can’t fix by analysis what you bungled by design.

—Light, Singer, and Willett (1990, p. viii)

It was pointed out previously that in the broadest sense, scientific observation is undertaken to achieve one of two goals. The goals are to describe situations and events more clearly and to identify relationships. The first chapters of this book dealt with the statistical procedures that are employed when describing data. Together, they are called, appropriately, descriptive statistics. Then, we introduced the concept of inferential statistics. Inferential statistics are the procedures we use to assist us in deciding whether relationships found in samples are likely to generalize ...