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Nonparametric Tests with Ordinal Data. Chapter 18. The sample data for the ordinal variable , accomplishment-related national pride, are skewed. This indicates the possibility that the underlying population distribution is skewed. . When both variables are ordinal Quantifies association
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Nonparametric Tests with Ordinal Data Chapter 18
The sample data for the ordinal variable, accomplishment-related national pride, are skewed. This indicates the possibility that the underlying population distribution is skewed.
When both variables are ordinal Quantifies association Calculating Spearman’s correlation Convert interval observations to rank-ordered observations Spearman Rank-Order Correlation Coefficient
The Wilcoxon Signed-Rank Test • A test for matched pairs is a nonparametric hypothesis test used when there are two groups, a within-groups design, and an ordinal dependent variable.
Steps for the Wilcoxon Signed-Rank Test • Step 1. Identify assumptions • Step 2. State null and research hypotheses • Step 3. Determine characteristics of comparison distribution • Step 4. Determine critical values • Step 5. Calculate the statistic • Step 6. Make a decision
Mann-Whitney U test • Nonparametric hypothesis test with two groups, a between-groups design, and an ordinal DV
Steps for the M-W U • Step 1. Identify assumptions • Step 2. State research and null hypotheses • Step 3. Determine characteristics of comparison distribution • Step 4. Determine critical values • Step 5. Calculate the statistic • Step 6. Make a decision
Kruskal–Wallis H Test • A nonparametric hypothesis test used for more than two groups a between-groups design, and an ordinal dependent variable.
Steps for the K-W H Test • Step 1. Identify assumptions • Step 2. State research and null hypotheses • Step 3. Determine characteristics of comparison distribution • Step 4. Determine critical values • Step 5. Calculate the statistic • Step 6. Make a decision
Bootstrapping • A statistical process in which the original sample data are used to represent the entire population. • We repeatedly take samples from the original sample data to form a confidence interval.