In psychological jargon, we call these attributes hypothetical constructs; in statistics, they are called factors or latent variables. One purpose of FA is to determine if numerous measures (these could…

A diagram of what this equation does is shown in Figure 20–1. For reasons that will become clear soon, we’ve drawn a box around each of the variables and a…

Measures of Association for Ranked Data This chapter reviews several measures of association for use with ranked data. Spearman’s rho is perhaps the most frequently used and is derived from…

Tests of Significance for Ranked Data Data that can be ranked (ordinal data) should be treated differently from categorical data. This chapter reviews several ranking tests—the Mann-Whitney test (or Wilcoxon…

The empirical way is also the basis for the old diagnostic dictum that if you hear hoof beats, it’s more likely to be coming from a horse than from a…

However, because of the nature of the syndrome, we are at liberty to do the study a little differently than the usual approach. Assuming that committees meet only every week…

OFVARIANCE CHAPTER THE SEVENTH Comparing Two Groups The t-Test The t-test is used for comparing the means of two groups and is based on the ratio of the difference between…

FIGURE 16-1 Individual relationship between Pathos Quotient (PQ) and Treatment (A), Belt size (B), and Age (C). TABLE 16–1 Data for 16 PMS patients TABLE 16–2 ANOVA of regression for…

You may wonder why we need three data points, since we can fit a perfectly straight line with only two. There are three answers to this: one methodological, one statistical,…

FIGURE 12-1 Men’s (left side) and women’s (right side) satisfaction scores, depending on who’s on top. The second problem is that of multiple testing. As we saw in Chapter 5,…