Descriptive Statistics and Univariate Analysis

Abstract

Results from an experiment will create numerous data points. The organization and summary of these data are termed descriptive statistics. This chapter presents the various ways to report descriptive statistics as numerical text and/or graphics. For qualitative (categorical) data, the use of tables, pie charts, and bar charts are the most appropriate ways to summarize the information. With quantitative (measurable) data, the researcher is interested in reporting both the center of the samples and the dispersion of data points around that center. Histograms, dot plots, and box-and-whisker plots are appropriate graphics for quantitative data. These descriptive statistics provide the information to be used for the inferential statistics discussed in later chapters. A univariate statistics involves the analysis of a single variable, whereas a multivariate statistic evaluates the differences, relationships, or equivalence for a dependent variable based on levels of an associated independent variable in the study design.