Randomize Between Groups (Experiment File)


All files sharing the same RBG value define a group of questionnaires or files to be kept together. If multiple groups are defined, then MediaLab will present them in a random order.


Any positive integer value


You may wish to randomly order and present entire groups of files in a given condition (e.g., randomizing whether personality questionnaires or demographic questionnaires come first). To do this, assign the same RBG value to all of the items you want to keep together. For example, if you have three groups of ten files in one condition, and you want to randomize the order in which these 3 sets of files are presented, then assign each group a different number and make sure all the files within each group share the same number for that group. The files within each group will all stay together, but the groups themselves will be randomly ordered. All files assigned a 0 or none will not move. Note that all files within a group must be sequential in the given condition.


In one condition, you want to present a Word document, five randomly ordered sets of five images, and a final Word document. Assign a value of "0" or none to the Word documents to keep them where they are, a "1" to the images in the first set, a "2" to the images in the second set, and so forth. That's it. To randomize the order that the files are presented within each group, see Randomize Within Groups .


Use of the RBG field in the experiment files randomizes the order of groups of questionnaires and related files, whereas using the RBG fieldRandomize Between Groups in the questionnaire files randomizes the presentation of groups items that generate the actual data.  Thus, use this functionality in the .exp file when you want to randomize the groups higher-level elements of your experiment (i.e., the questionnaires themselves).