Analysis of Longitudinal Data: Hierarchical Linear Modeling
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,…
Multivariate ANOVA (MANOVA)
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,…
Equivalence and Non-Inferiority Testing
versus the alternative hypothesis (HA) that the parameters aren’t equal: But, the null hypothesis doesn’t always have to postulate no difference between or among the groups. Null, in this case,…
Getting Started with SPSS
Notice that in the lower left corner, there’s one tab labeled Data View and another called Variable View (which is the screen we’re in now). Clicking on these allows you…
Screwups, Oddballs, and Other Vagaries of Science
CHAPTER THE TWENTY-EIGHT Screwups, Oddballs, and Other Vagaries of Science Locating Outliers, Handling Missing Data, and Transformations In this chapter, we discuss ways of locating anomalous data values, how to…
Measuring Change
TABLE 17–2 ANOVA of pretest and post-test scores for the RCT of RRP If that’s all we did, then the straightforward analysis is, as we already indicated, an unpaired t-test…
Two Repeated Observations
. So the test, called a paired t-test, is equal to: TABLE 10–1 Pretest and post-test weights of 12 Casimir subjects In this case, it equals . Now, the critical…
Putting It All Together
Putting It All Together In this chapter, we provide some final signposts: (1) flow charts to help you select the right test, (2) simplified tample-size calculations, and (3) names of…
The Normal Distribution
FIGURE 4-1 Theoretical distribution from rolling a die 600 times. FIGURE 4-2 Computer simulation of averaging the sum of rolling the die 2, 4, and 8 times, each done 600…
The Basics
NATUREOFDATAANDSTATISTICS CHAPTER THE FIRST The Basics In this chapter, we will introduce you to the concepts of variables and to the different types of data: nominal, ordinal, interval, and ratio….
