Kruskal-Wallis Test: Concept, Assumptions & Procedure

Introduction

The Kruskal-Wallis test, easy to execute with SPSS help, originally is a particular non-parametric and an alternative method other than the One-Way ANOVA technique. The Kruskal Wallis test process is mainly applied for comparing the groups which could be a least three or more than that as being a dependent variable and measures on at least an ordinal level. The Kruskal Wallis test in the SPSS data analysis test also determines whether the significant group medians of two or more will be different. To be taken as a pattern of the Kruskal Wallis Test, it is said to be seen that the Kruskal Wallis Test SPSS is understandably related to the matter of evaluating the exam performances of the students. This evaluation can measure the performances calculated on a continuous measuring scale of 0-100 and it is not dependent on the varied anxiety levels of the students included in this Kruskal Wallis test SPSS. In this regard, the “exam performances of students” is the dependent variable in this test and the independent variable is their “anxiety level” on the test.

Kruskal Wallis Test Concept

When talking about a non-parametric method or technique, it signifies such a method where the tests don’t have the nature to assume the data that is gained from a specific distribution. The Kruskal Wallis test SPSS is based on the rank and non-parametric measuring test that is applied to determine the presence of any kind of statistical significance of differences among two or more two independent variable groups based upon the ordinal or continuous type of dependent variable. In different cases, different categories of attitudes are evaluated on the ordinal measuring scale depending on a variety of job positions. The “attitude towards pay differentiation” is calculated on a particular scale with 5 points initiated from "strongly agreed" to "strongly disagreed" step by step. Further, the “job description” is consisted of three different independent groups – the initial stage, middle management, and decision-making room. The Kruskal-Wallis test in anxiety level is taken to have three varied independent groups - low, medium, and high. While performing the Kruskal-Wallis test applied in the SPSS help data analysis, there is an interpretation of the factor analysis of the variables after that the reports or results are attained from that test. Another instance of the Kruskal Wallis test usage understands the attitude toward the employee payment difference. Here, the dependent variable is the “attitude towards pay differentiation” and the independent variable is the “job description”.

Kruskal-Wallis Test Assumptions

A few assumptions relevant to the Kruskal Wallis rank test applied in the SPSS software program are:

1. Assumption 1 is the dependent variable is calculated based on the ordinal type or upon the continuous level type such as an interval or ratio categories or of other methods involved in the Kruskal Wallis Test SPSS.
2. Assumption 2 is an independent variable that consists of two or greater than two categorical forms in case of an independent group to have a minimum of three or higher than three categories of independent groups. However, this can only be utilised when there are two groups.
3. Assumption 3 is necessary must have a feeling of independence about presenting the observations. Kruskal Wallis test service shows there has to be no connection among the different observations present in each group also it must not create any relationship also between the groups, themselves.
4. Assumption 4 says that for interpreting and achieving the Kruskal Wallis rank test results, it is essential to determine which is important during testing regarding the distribution of the scores among each independent variable of every group having the same variability shape or not.

Kruskal Wallis Test Procedure

A list of steps, showing the analysing process of the raw data input applying the Kruskal Wallis test service in the SPSS helps the statistical data analysis program. After finishing, after completing all the steps, the process will present the interpretation procedure of the results from this Kruskal-Wallis test –

1. First, open the SPSS program > move towards Analyse option > go to the Non-parametric Tests option > then move to the Legacy Dialogs option > then press the K Independent Samples option.
2. The "Tests for Several Independent Samples" dialogue box will appear > tick the “Kruskal-Wallis H” checkbox by selecting it to make the Kruskal-Wallis test run on the transferred variables in the next step.
3. Transfer all dependent variables in the “Test Variable List” section and all independent variables in the “Grouping Variable” section.v
4. Press the “Define range” button which opens the "Several Independent Samples: Define Range" window box.
5. Next, enter "1" in the “Minimum box” section and "3" in the area of “Maximum box”. These values represent the code ranges of the independent variable groups.
6. Next press the “Continue” switch which will take you back to the "Tests for Several Independent Samples" window box, with a fulfilled “Grouping Variable” dialogue box.
7. After that, go to the “Options” button and click on it to present the "Several Independent Sample Options" window.
8. Next choose the “Descriptive” checkbox, in case it has descriptives as requirements and/or the “Quartiles” checkbox if the medians and quartiles are the necessities.
9. After that click on the “Continue” switch to return the "Tests for Several Independent Samples" window again.
10. The final step is clicking the “OK” button to generate the final results.

However, initiating the whole process understands all the various categories of assumptions present in the SPSS help software program where the raw data must cover the overall Kruskal Wallis rank test to achieve the final valid result.

Conclusion

When talking about a non-parametric method or technique, the Kruskal Wallis rank test signifies such a method where the tests don’t have the nature to assume the data that is gained from a specific distribution. As an instance of the Kruskal Wallis test usage understands the attitude toward the employee payment difference. This process is mainly applied for comparing the groups which could be a least three or more than that as being a dependent variable and measures on at least an ordinal level. Also, there is a list of steps that shows the analysing process of the raw data input applying the Kruskal Wallis test in the statistical SPSS data analysis. And regarding this, it is to be taken as a pattern of the Kruskal Wallis Test, it is said to be seen that the Kruskal Wallis test is understandably related to the matter of evaluating the exam performances of the students.