Avoid same type of item twice in a row in loop

mariee

I have a bunch of items in my loop that belong to the same type. I want everything in the experiment to be randomized, but ideally, I would like to avoid that participants see the same type of item twice in a row.

To illustrate, here is an example; I have 9 items of 3 different types:

*breed*    *animal*
poodle     dog
corgi      dog
malinois   dog
siamese    cat
persian    cat
bengal     cat
arabian    horse
appaloosa  horse
mustang    horse

At the moment, everything from this list is selected completely at random. Therefore, it can happen that for example two "cat" items are shown after each other (e.g. siamese comes directly after persian). If possible I'd like to avoid this, so that it will never happen that two cat (or dog or horse) items are shown one after another. So a valid order would be for example: poodle, siamese, mustang, persian, malinois, arabian, etc..

Is this possible, and if so, how?

sebastiaan

Hi @mariee ,

You can use the maxrep constraint by editing the script of the loop item and adding the following command (after all setcycle commands):

constrain animal maxrep=1

See also:

• https://osdoc.cogsci.nl/3.3/manual/structure/loop/#pseudorandomization

Cheers!

Sebastiaan

mariee

That seems to work, thanks! :)