One-Way ANOVA in SPSS
Calculating One-Way ANOVA in SPSS
To calculate One-Way ANOVA, we will take the Employee data set, which is given below:
In this data set, we have a variable called jobcat. Now, if we look at the jobcat variable, we find that jobcat has three levels. If we click on the Values option, there are people from three different job categories, i.e., Clerical level, Custodial level, and Managerial level. 0 stands for the missing value. That is a good way of defining missing value. 0 has been defined as a missing value, and they have kept in the missing value option. It means if we calculate any stat, for example, we want to do One-Way ANOVA, 0 will not be counted as a variable.
We want to find out that people belonging to different job categories will be drawing significantly different amounts of salary. To be more precise, we want to make a test. In which we can say that Managers are drawing significantly more amount to salary as compare to custodial or clerical people. So we hypothesize that when we move from the clerical level to the managerial level, there is an increase in salary. We can test it by using One-Way ANOVA. So we have two variables here. One is an independent variable that is jobcat, which has three levels and one dependent variable, i.e., current salary. Now once all variables are defined, we will move to the calculation of One-Way ANOVA. To calculate One-Way ANOVA, we will go Analyze menu, and Compare Means and then One-Way ANOVA.
The symbol of One-Way ANOVA is F a. So F stands for the Ronald fisher, the person who gives this test. When we click on One-Way ANOVA, we will see a dialog box like this:
All the variables are populated on the left-hand side. So we have to select our dependent variable in the Dependent List and independent variable in Factor. So our dependent variable is the Current salary, and the independent variable is Job category, so we will select it.
By going to the Options tab, we can look at the Descriptive statistics like this:
Now we are ready to test the significant differences between three salary groups, three job categories. So click on, Ok. The following is the output for One-Way ANOVA.