Tutorial: RBG + RWG (15/21)


…\DirectRT\samples\3 ordering trials\rbg rwg.csv


Can you guess what's next? That's right, we can combine RBG and RWG values to randomize the order in which sets of items occur (RBG), and also the order of the trials within those sets (RWG). Open up the input file and you can see that we have values for both RBG in the bgr column and RWG in the wgr column.

Run the session and see what happens. Can you predict?

Notice trials 11-14. They all belong to the same RBG block which means that set of trials may come 1st, 2nd, or 3rd out of the three RBG groups. However, unlike set 1 and 2, they all have an RWG value of 0. That means they will appear in their original order within the group. In contrast the trials within RBG groups 1 and 2 will be randomized.

Note also how trials 1, 6 and 10 each have 0's for both RWG and RBG. This means they will stay exactly where they are-in the 1st, 6th, and 10th position respectively.

As an exercise, play with the RBG and RWG values and see if you can predict the effects on the session. Just remember that the only constraint in doing this is that trials sharing the same RBG value need to be located next to each other in the input file.