plugaggregate: a gui to average across and within subjects

Command: PlugAggregate.

When running an experiment, usually one wants to analyze different combinations of trial conditions. Therefore, one approach consists in coding and averaging all conditions as many times as the number of comparisons one wants to inspect. However, a more efficient approach consists in coding the first time the smallest possible conditions, and then average them together to examine specific combinations.
For instance, if one has a Latin square design comparing red and green squares and circles,

Circle Square
Red | 1 | 2
Color -----------------
Green | 3 | 4

then one has a total of four conditions (which will be named .at1, .at2, .at3 and .at4). In order to compare circles (both green and red) to squares (both green and red), one should combine condition 1 with condition 3, and condition 2 with condition 4. Emegs allows to do this either by using command-line programs, or using the PlugAggregate plugin.
As all Emegs plugins, it can be called either as a standalone program by calling PlugAggregate from the Matlab command line, or using the Aggregate files entry in the Plugin menu.

The PlugAggregate window contains buttons to load an .agg file, run the analysis and close the window.

The PlugAggregate window contains options to recursively operate on data structured with one directory per subject, to delete old aggregate files, and to create grandaverages (across subjects).

What PlugAggregate needs to operate is an .agg file which specifies the way conditions will be combined, the name the averages will have, and contains comments e.g. on the condition names. To combine red with green circles and squares, one should use the following .agg file:

% Circles and Squares.agg
% by Andrea De Cesarei
% condition 1: circles
% condition 2: squares
1 3
2 4

The file contains:

To use the aggregate file, click on LoadConditions, and check that the file is loaded correctly.
Then, choose whether the program will work recursively (e.g. different directory for each subject) or just in the specified directory. Choose also if you want to keep or delete old averages, and if the program should create grandaverages (tested only in recursive mode). When all is set, push Run Aggregate and create a dummy file in the top(or target) directory.

The program will create two files, named which will contain the average of conditions 1 and 3, and the file containing the average of conditions 2 and 4.

Optionally, the top folder will also contain files called which contain the grandaverage across subjects of the specified conditions.