Transforming data using the stack/unstack function
Goal of this tutorial
We have obtained results from an experiment with one column per group. We wish to run a one-way Analysis of variance on these results. The data has to be transformed so that an ANOVA can be applied.
Dataset for stacking variables
An Excel sheet with both the data and the results can be downloaded by clicking here. In this tutorial we show how to stack variables in order to run an analysis of variance.
The dataset contains three columns, each one attached to a group of patients.
After opening XLSTAT, select the XLSTAT / Preparing data / Data Management command, or click on the corresponding button of the Preparing data menu (see below).
Once you've clicked on the relevant button, the dialog box appears. Select the method, we use stack. Select the data you want the stack function to be applied to in the data field.
Once you have clicked on the OK button, the results are displayed on a new sheet.
Results of the stacking process
The only result that is displayed is the transformed dataset. Instead of having 3 columns, it contains 2 columns, the first one indicating the group and the second one the value of the transformed variable.
You can now apply a one-way ANOVA on the obtained dataset. Here is a detailed tutorial on one-way analysis of variance.
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