Millisecond Forums

Random pairs

https://forums.millisecond.com/Topic22879.aspx

By YL - 11/16/2017

Hi I am having trouble with randomization of stimulus pairs. The related topic I searched was from the forum Inquisit 2.0. The solution is very cumbersome. Is there any new way to do this with version 5?

For example, I have stimulus pairs A (pic1, pic2;  pic1,3 etc...), B(pic2, pic3;  pic3,4 etc...), C(pic2, pic2; pic1,3 etc...) I want to present stimulus pairs A, B, C the fixed number of trials but random across the block. Each stimulus pair is randomly drawn from lists A, B, C. Is there a way to represent stimulus pairs within a list?

Thanks!
By Dave - 11/16/2017

YL - Thursday, November 16, 2017
Hi I am having trouble with randomization of stimulus pairs. The related topic I searched was from the forum Inquisit 2.0. The solution is very cumbersome. Is there any new way to do this with version 5?

For example, I have stimulus pairs A (pic1, pic2;  pic1,3 etc...), B(pic2, pic3;  pic3,4 etc...), C(pic2, pic2; pic1,3 etc...) I want to present stimulus pairs A, B, C the fixed number of trials but random across the block. Each stimulus pair is randomly drawn from lists A, B, C. Is there a way to represent stimulus pairs within a list?

Thanks!

Yes, you can represent your pairs as pairs of item numbers in linked <list> elements. You then sample from those pairs randomly. See e.g. https://www.millisecond.com/forums/FindPost22774.aspx or https://www.millisecond.com/forums/FindPost22698.aspx

For the different stimulus categories (A, B, or C) you'll probably want to set up separate <trial> elements (one for A, one for B, one for C) and then sample those at the <block>-level in the desired fashion.

Hope this helps!