Millisecond Forums

Randomization, self-paced reading study

https://forums.millisecond.com/Topic17873.aspx

By mrtncgy - 12/2/2015

Hello, 

I am conducting a self-paced reading study and my stimuli are divided into 5 different categories. (Different, types of sentences, fillers included.)
I was wondering whether there is a (simple) way how to program it in a way when two items of the same type don't 
appear next to reach other. I am using script downloaded from the library here, just slightly adjusted. 

Since I am a complete beginner, I would really appreciate if you could provide examples from the script.

Thank you for your help.
By Dave - 12/2/2015

You need to introduce a <list> that encodes your 5 categories, linked to the respective items. You enforce the "no two categories of the same type in a row" constraint via the <list>'s /maxrunsize attribute. For details see the attached script. It assumes 5 categories, with 2 items per category (10 items total). The main changes are in <list mwstims> and the use of list.mwstims.nextindex as opposed to list.mwstims.nextvalue in <trial getstim>.
By mrtncgy - 12/6/2015

Hello Dave, 

thank you ver much for your respond. It is working perfectly.
Nevertheless, I tried to add more sentences (I have 5 groups of sentences and each group contains 16 sentences, together 80 sentences.)
and I sucked there. I do realize that I do need to ch change something in the script you sent me but I can not figure out
what it that. 

Do you think you could help me with that? 

Thank you very much. 
By mrtncgy - 12/6/2015

Sorry for that post with so many typos. I was / am way to excited about that experiment. Also, my autocorrector just changed some words there.
I hope you will be able to get back to me. 

Thanks. 
By Dave - 12/6/2015

You have five categories (1-5), with 16 items each. List each category 16 times in <list mwstims>:

<list mwstims>
/ items = (1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
    3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
    4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
    5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5)
/ selectionmode = random
/ maxrunsize = 1
</list>

Enter your 5*16 = 80 items in <item mwstims>:

<item mwstims>
/ 1 ="|Category 1| Item 1|"
/ 2 ="|Category 1| Item 2|"
/ 3 ="|Category 1| Item 3|"
/ 4 ="|Category 1| Item 4|"
/ 5 ="|Category 1| Item 5|"
/ 6 ="|Category 1| Item 6|"
/ 7 ="|Category 1| Item 7|"
/ 8 ="|Category 1| Item 8|"
/ 9 ="|Category 1| Item 9|"
/ 10 ="|Category 1| Item 10|"
/ 11 ="|Category 1| Item 11|"
/ 12 ="|Category 1| Item 12|"
/ 13 ="|Category 1| Item 13|"
/ 14 ="|Category 1| Item 14|"
/ 15 ="|Category 1| Item 15|"
/ 16 ="|Category 1| Item 16|"

...

/ 65 ="|Category 5| Item 1|"
/ 66 ="|Category 5| Item 2|"
/ 67 ="|Category 5| Item 3|"
/ 68 ="|Category 5| Item 4|"
/ 69 ="|Category 5| Item 5|"
/ 70 ="|Category 5| Item 6|"
/ 71 ="|Category 5| Item 7|"
/ 72 ="|Category 5| Item 8|"
/ 73 ="|Category 5| Item 9|"
/ 74 ="|Category 5| Item 10|"
/ 75 ="|Category 5| Item 11|"
/ 76 ="|Category 5| Item 12|"
/ 77 ="|Category 5| Item 13|"
/ 78 ="|Category 5| Item 14|"
/ 79 ="|Category 5| Item 15|"
/ 80 ="|Category 5| Item 16|"
</item>