  Quiz (Chapter 18) Statistical Tests on Ranks (Nonparametric Tests) Introduction The simplest kind of quantitative data involve _____. Test procedures such as the median test and the Mann-Whitney U test are called ______ tests. Obtaining Ranked Data In how many different ways can a researcher "produce" data that take the form of ranks? In Excerpt 18.6, the 1-to-10 numerical ranks assigned to each participant's sorted pictures indicated a _______ ordering of the pictures. least preferred to most preferred most preferred to least preferred Reason for Converting Scores on a Continuous Variable into Ranks Test procedures designed for use with ranks involve ____ (fewer/more) assumptions than procedures designed for use with interval- or ratio-level data. Unequal or small sample sizes prompt many researchers to ____ (use/not use) tests based on ranks. (T/F) The total scores people earn on a Likert-type attitude inventory are probably only ordinal in nature. The Median Test The median test is used to compare 2 or more groups that are _____ (independent/correlated). In comparing 3 groups with a median test, how many medians would appear in the test's null hypothesis? In comparing 3 groups with a median test, how many medians need to be computed from the sample data? The calculated value in a median test is referred to as ___. t F c2 (T/F) Excerpt 18.14 shows that a median test's p-value gets smaller as the calculated value gets larger. The Mann-Whitney U Test The Mann-Whitney U test test is used to compare 2 groups that are _____ (independent/correlated). Of the two test procedures referred to in Excerpts 18.1 and 18.2, which one is more powerful? The task of interpreting a significant result from a Mann-Whitney U test is _____ (easy/difficult). (T/F) If the U test leads to a rejection of Ho, the populations might differ in their means, medians, or modes. Excerpt 18.15 shows that there is a ______ (direct/indirect) relationship between the size of U, the calculated value, and the size of p. The Kruskal-Wallis H Test The Kruskal-Wallis H test is used to compare 3 or more groups that are _____ (independent/correlated). (T/F) In both the Kruskal-Wallis and Mann-Whitney tests, a "sum of ranks" is computed for each sample. (T/F) In Excerpt 18.18, the number immediately to the right of each H in the final sentence would have been a ___ (rather than a 2) if there had been 5 music conditions in the study. In a Kruskal-Wallis test, Ho is rejected if the calculated H is ____ (smaller/larger) than the critical value. In Excerpt 18.20, how many Mann-Whitney U tests were conducted? The Wilcoxon Matched-Pairs Signed-Ranks Test Wilcoxon's test is used to compare __ (how many?) sets of scores that are _____ (independent/correlated). The calculated value in a Wilcoxon matched-pairs signed-ranks test is referred to by what capital letter? In Excerpt 18.21, the 1st sentence indicates that data from the control group were gathered at 3 points in time: pretest-1, pretest-2, and posttest. The 2nd of these points of data collection is referred to as ____ later in the excerpt. pretest-1 pretest-2 posttest-1 posttest-2 In a Wilcoxon test, Ho is rejected if the calculated value is ____ (smaller/larger) than the critical value. A significant T suggests that the 2 populations differ in what way, assuming they have the same shape? Friedman's Two-Way Analysis of Variance of Ranks Friedman's test is used to compare __ (how many?) sets of scores that are _____ (independent/correlated). Which parametric ANOVA is analogous to the Friedman two-way analysis of variance of ranks? If each of 3 people tastes 3 soft drinks and then ranks them, what should you expect the "sum of ranks" to be for any of the beverages if the null hypothesis (that the 3 beverages are equally good) is true? In Excerpt 18.22, which number in the excerpt is the Friedman test's calculated value? .05 9 10 48.47 If the Friedman test yields a significant result, what test is likely to be used in a post hoc investigation? Large-Sample Versions of the Tests on Ranks; Ties (T/F) A test on ranks made via a z-test (due to large samples) can be thought of as a "normal curve test." The _____ test can be thought of as the "small-sample" version of the median test. (T/F) Excerpt 18.24 shows that the large-sample approximation to a Kruskal-Wallis test has a calculated value represented by z. The regular median test is inherently a ______ (small-sample/large-sample) test. (T/F) When ties occur in tests on ranks, the only thing a researcher can do is discard the tied scores. The Relative Power of Nonparametric Tests (T/F) Under certain circumstance, nonparametric tests have more power than their parametric counterparts. Applied researchers should explain why they used the specific tests selected to analyze their data, and the issue of _____ _____ ought to be included in such explanations. A Few Final Comments Nonparametric tests ___ (are/are not) based on the assumption that the data come from random samples. The last sentence in the 2nd paragraph on p. 496 urges you not to use _____ as the criterion for judging the worth of empirical studies. Click here for answers.