  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 18.2, what data were used in computing the Spearman correlation? The 1st of the 2 numbers recorded by the 2nd researcher. The 2nd of the 2 numbers recorded by the 2nd researcher. 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) If, in Excerpt 18.10, group C's median healing time had been 12 weeks (rather than 14 weeks), the null hypothesis might have been rejected. The Mann-Whitney U Test The Mann-Whitney U test test is used to compare 2 groups that are _____ (independent/correlated). In the study associated with Excerpt 18.11, the sums of ranks for the 2 institutions were quite _____ (similar/different). 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. 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. The information in Excerpt 18.12 shows that there is a(n) _____ (direct/indirect) relationship between the size of H and the size of p. In a Kruskal-Wallis test, Ho is rejected if the calculated H is ____ (smaller/larger) than the critical value. In Excerpt 18.14, how many Mann-Whitney U tests were conducted in the post hoc investigation following the significant Kruskal-Wallis result? 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 18.15, what would have happened to T and p if the two sums of ranks had been more similar? Both T and p would have been smaller. T would have been larger but p would have been smaller. T would have been smaller but p would have been larger. Both T and p would have been larger. 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? Read Excerpt 18.16 and the paragraph above it. Based on these descriptions of the study, how many sets of ranks were there? 3 25 49 It's impossible to tell based on the information provided. 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. In Excerpt 18.17, which number(s) allow us to know that data came from more women that men? The 3 means (12, 16, and 5) The standard deviation (21) The calculated value, z (-7.15) The probability, p, associated with z (<.001). 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. A Few Final Comments Nonparametric tests ___ (are/are not) based on the assumption that the data come from random samples. In Excerpt 18.11, the means and standard deviations for the two samples ____ (do/don't) suggest the presence of "overlapping distributions." The last sentence in the 2nd paragraph on p. 454 urges you not to use _____ as the criterion for judging the worth of empirical studies. how large or small the sample size is how "impressive" the data-based p-level is what alpha level was used whether Ho is or isn't rejected Click here for answers.
 Copyright © 2012 Schuyler W. Huck All rights reserved. | Book Info | Author Info | Site URL: www.readingstats.com Top | Site Map Site Design: John W. Taylor V