nonparametric tests with ordinal data
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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 - PowerPoint PPT PresentationTRANSCRIPT
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.
Spearman Rank-Order Correlation Coefficient
> When both variables are ordinal> Quantifies association> Calculating Spearman’s correlation
•Convert interval observations to rank-ordered observations
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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
Formulae
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212 2)1())(( RnnnnU
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
Formulae
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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.