Problems with randomization using Direct RT

[Emily]

Hi,

I'm having problems with randomization when using Direct RT. The procedures of the experiment is as follows:

1. ******** 1000 ms
2. Picture 1000 ms
3. Target word response
4. Blank screen 2000 ms

Total number of trials: 12 pictures x 16 target words = 192 trials
2 breaks, 64 trials in each block, altogether 3 blocks

I can't think of a way of having Direct RT to randomly display each of these 192 trials (where each priming picture matches with each target word). The methods I have used would only randomly select from the pictures and target words. This means there is some repetition in the pairing of the pictures and words, and that some (picture and word pair) trials can't be displayed.

How can I overcome this problem?
Thank you very much for your help!

Emily

[Trevor Newell]

Hm. At first it would seem like StimLists might do the best job at what you need completed; however after contemplating the issue for a bit, it seems as though you may be better off simply making a trial for each pairing, and then using the WGR and BGR features to randomize the trials for you. If you make a trial for each pairing, you'll be able to have the WGR and BGR features properly randomize the trials for you - while making sure that each pairing still has the chance to be displayed.

For more information, look here:
RWG: http://www.empirisoft.com/directrt/help/directrt_samples_rwg.htm
RBG: http://www.empirisoft.com/directrt/help/directrt_samples_rbg.htm
RWG + RBG: http://www.empirisoft.com/directrt/help/directrt_samples_rbg_rwg.htm