When it comes to univariate analysis of variance SPSS APA format table favors the ANOVA approach. This is much as you would expect given its prevalence throughout the social and healthcare sciences. Measuring one dependent variable for one or more factors is simple when you follow the correct approach. Get in touch for expert help with your statistical analysis.

## Why Is ANOVA So Useful?

The main reason why SPSS univariate analysis of variance in the form of ANOVA is so handy is that you can use it to deal with data from experiments having more than two conditions. Using ANOVA for data management is great for working out whether the change in a single independent variable has affected the values of any dependent variables.

Despite its obvious usefulness, SPSS univariate analysis of variance cannot do everything at once. For example, you can’t use ANOVA to find out which pairs of conditions are significantly different. You’ll need to apply a few extra techniques to compare specific means.

## When to Use ANOVA

Statistical tests involve the use of finely tuned formulae that have been developed over years of research by some of the smartest mathematicians ever to have lived. Although using SPSS to conduct statistical tests is a largely automated process once you’ve inputted all your data in the correct format, you still need to understand which conditions have to be met in order to run particular tests.

A test that has been used inappropriately is essentially worthless as it doesn’t give you any meaningful insight into your data. You can only use ANOVA properly if your data meets the following criteria.

- The data for your dependent variable must be interval or ratio data in its nature.
- The populations used must be normally distributed.
- You must have equal population variances.
- If you’re using an independent groups design, you need to make sure that your independent random samples have been taken from each population.

## How to Know Whether an ANOVA Result is Significant

There are several things that Cronbach’s alpha SPSS will do automatically so that you can understand whether your data is significant. It’s worth understanding the statistical basis upon which any such conclusion is made. One of the main advantages of using ANOVA is that it compares variance due to nuisance factors to variance due to your manipulation of the independent variable. This enables you to find out whether the former, also known as the error variance, is less than the latter.

The best way to express this is as a ratio of the variance due to manipulation of the independent variable and the error variance, that is to say the F-ratio. The larger the F-ratio, the greater the effect of the independent variable compared to the so-called noise. As such, when an F-ratio is equal to or less than 1, the result is non-significant. The reason for this is that it shows that the results were equally or more affected by nuisance variables.

## How to Conduct ANOVA in SPSS

There are are number of different kinds of ANOVA testing and which one is most appropriate to use depends on exactly what you’re trying to accomplish. You can examine variance in four basic ways as outlined below.

- One-way between-subjects
- Two-way between-subjects
- One-way within-subjects (another way of describing the repeated measures analysis of variance SPSS conducts)
- Two-way within-subjects

If you have the right kind of data collection to conduct repeated measures analysis of variance SPSS makes this rather straightforward. Let’s consider one-way within-subjects ANOVA here before moving on to other kinds.

- Select the Analyze menu in the toolbar at the top of the screen. Hover over the General Linear Model item and click on Repeated Measures in the menu that pops up. You’’ end up at a dialog box entitled Repeated Measure Define Factor(s).
- Change the Within-Subjects Factor Name to “list”, for example. Type in the number of levels your data set has, and then click the Add button. Now you can click the Define button to bring up another dialog box.
- Move the variables in your Within-Subjects Variables box until they fit the statement laid out in your hypothesis. Then, click the Options button to open yet another dialog box.
- In the display section, check the Descriptive Statistics box to obtain a mean average and standard deviation for each of the levels in your factor. Check the Estimates of Effect Size box to get a partial Eta squared result. Click Continue to go back to the Univariate dialog box.

## Understanding Two Way ANOVA Interaction

Two way ANOVA interaction stems from testing that is essentially an extension of the one-way approach, the difference being that there are two independent variables, each known as factors. Interaction here refers to the effect of one such factor on the other.

The two way mixed ANOVA is a way of testing the differences between at least two independent variables while participants are subjected to repeated measures as outlined above. In this two way mixed ANOVA, one factor is a between-subjects variable and is thus known as a fixed effects factor, whereas the other factor is a within-subjects variable and is known as a random effects factor.

The best way to understand the difference between all these different kinds of ANOVA is to ask an expert statistician with years of practice in using these tests. Learning from real-life applied examples is the only real way to learn statistics properly.

When it comes to running tests like univariate analysis of variance SPSS is a fantastic tool. You can do any of these tests automatically as long as you provide the correct kind of data as outlined in the criteria above. If you’re struggling with any aspect of statistics, ask an expert for their sage words of advice and you’ll quickly get a handle on things.