In Using the Kruskal-Wallis Test, There Is a Correction Factor $$1 - \frac { \sum \mathrm { T } } { \mathrm { N } ^ { 3 } - \mathrm { N } }$$

question 52

Multiple Choice

In using the Kruskal-Wallis test, there is a correction factor that should be applied whenever there are many ties: Divide H by $$1 - \frac { \sum \mathrm { T } } { \mathrm { N } ^ { 3 } - \mathrm { N } }$$ For each group of tied observations, calculate $\mathrm { T } = \mathrm { t } ^ { 3 } - \mathrm { t }$ , where $\mathrm { t }$ is the number of observations that are tied withi the individual group. Find $\mathrm { t }$ for each group of tied values, then compute the value of $\mathrm { T }$ for each group, then add the T values to get $\sum \mathrm { T }$ . The total number of observations in all samples combined is N. Find the corrected value of $\mathrm { H }$ for the data below which represents test scores for three different groups.
$\begin{array}{lllllll}\text { Group 1: } & 20 & 18 & 18 & 18 & 20 & 20 \\\text { Group 2: } & 18 & 12 & 18 & 18 & 20 & \\\text { Group 3: } & 16 & 18 & 13 & 18 & 18 &\end{array}$

• A) \(3.69\)
• B) \(- 0.19\)
• C) \(4.91\)
• D) \(3.78\)

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