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EEG and MEG studies are most often analyzed with a special kind of analysis of variance, that accounts also for within subject changes rather than only for between subject differences. EMEGS offers the possibility to calculate this kind of analysis directly, without exporting the data to a separate statistic software package. At the present time, only single region-of-interest analyses are supported. Pointwise analyses on all sensors are under construction.

ANOVAs require the R environment for statistical computing to be setup correctly, as described here.

1. Prepare data files and batch

To run a repeated measures ANOVA, prepare your data as follows: each condition for every subject has to be saved as an SCADS average file. Every file has to have the same number of points and number of channels. You need a batch listing the paths of those files on your machine.This batch must be setup using the batch docking window and has to reflect the design of the planned analysis, that is, your paths have to be listed according to the

Cells need to be ordered from lowest hierarchy position of the factor to highest hierarchy position. For instance, consider a 2x2x2 design with the factors 'task' (count forward vs count backward) , 'color' (count red squares vs. count green squares) and 'gender'. Thus, your batch for 16 subjects for this design has to have the following form:

2. Set Interval and Sensor group settings

Select from the Calculate menu ANOVA::Run ANOVA, and on the value export page of the displayed dialog, make sure that the displayed summary of the calculations is correct (includes Baseline, Group and Intervals):

3. Enter the factorial design on the Calculate: ANOVA dialog

Then enter your statistical design and second page as shown below:

4. Set the design

Push the large set factorial design button on the bottom right corner, to have EMEGS check the design correspondance with the current batch. If inconsistencies are found, you will get an error message, otherwise, the Ok button is enabled, which you push to start the ANOVA.

5. Check Export- and ANOVA-log

During the value export, EMEGS writes messages to the log docking window. If the log window is not visible