Millisecond Forums

Hi,

I am trying to create an experiment in which we have 4 blocks with randomized trials: Block A_positive, Block A_negative, Block B_positive, and Block B_negative. I'm wondering if there's a way to randomize the order that the blocks are shown, but still keep the two Block As together and Block Bs together. In other words, I'm trying to achieve two levels of randomization. I'd like to randomize whether block A or block B is shown first, and then randomize whether positive or negative is shown first within those blocks. It seems like group assignment would be the best way to go about this, but I'm not sure how to write the code. Any help with this would be much appreciated!