{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

inclass_oct18 - var resp run The ﬁrst and third screens...

This preview shows pages 1–2. Sign up to view the full content.

Stat 296 Fall 2007 The Kruskal-Wallis Test Example: For Example 3.1.1 on page 81, we can apply the Kruskal-Wallis test to the ranks. The data is as follows: Samples from normal populations with μ 1 = 15, μ 2 = 25, μ 3 = 30, σ = 9. Treatment 1 6.08 22.29 7.51 34.36 23.68 Rank 1 1 3 2 13 5 Treatment 2 30.45 22.71 44.52 31.47 36.81 Rank 2 9 4 15 10 14 Treatment 3 32.04 28.03 32.74 23.84 29.64 Rank 3 11 7 12 6 8 Since there are 756,756 possible permutations, the exact Kruskal-Wallis test will take a signiﬁcant amount of time to run. Instead, we use the MC option which randomly samples 10,000 permutations. data oct18; input treat resp @@; cards; 1 1 1 3 1 2 1 13 1 5 2 9 2 4 2 15 2 10 2 14 3 11 3 7 3 12 3 6 3 8 ; proc npar1way data=oct18 anova scores=data; class treat; exact scores=data /MC; /* The MC option randomly samples the permutations */

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: var resp; run; The ﬁrst and third screens displayed by SAS are as follows. The NPAR1WAY Procedure Analysis of Variance for Variable resp Classified by Variable treat treat N Mean---------------------------------------1 5 4.80 2 5 10.40 3 5 8.80 Source DF Sum of Squares Mean Square F Value Pr > F-------------------------------------------------------------------Among 2 83.20 41.60 2.5366 0.1206 Within 12 196.80 16.40 The NPAR1WAY Procedure Monte Carlo Estimate for the Exact Test Pr >= Chi-Square Estimate 0.1281 99% Lower Conf Limit 0.1195 99% Upper Conf Limit 0.1367 Number of Samples 10000 Initial Seed 725846367 In this case, we ﬁnd a p-value of 0 . 1281. This is not very signiﬁcant evidence to reject H ....
View Full Document

{[ snackBarMessage ]}

Page1 / 2

inclass_oct18 - var resp run The ﬁrst and third screens...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online