INTRODUCTION

The last two chapters of this book cover the field of statistics, from a basic introduction through multivariate analysis. Social scientists regularly encounter quantitative data that have been summarized and presented in statistical form. They find statistics in almost everything they read, from articles in popular newspapers and magazines to scholarly journals. Published reports of the results of quantitative research usually include charts, diagrams, graphs, and tables. To evaluate such work, it is essential to develop a thorough understanding of statistical procedures, including the assumptions and limitations underlying each technique. The purpose of this chapter is to outline the basic procedures, ideas, and issues associated with the analysis of quantitative data.

UNIVARIATE ANALYSIS

A distinction is often made between descriptive research, which highlights the outstanding characteristics of a sample, or of the population from which the sample was drawn, and explanatoryresearch, which concentrates on cause–effect connections among those characteristics. In practice, most quantitative studies involve elements of both description and explanation, beginning with a descriptive statistical summary of the data and progressing toward testing hypotheses and causal relationships. Descriptive analysis typically involves consideration of one variable at a time rather than the relationship between two or more variables. For this reason, it is often referred to as univariate analysis.