2 different block loop with the same trials randomisation

bilancino

Dear all,

I have to create an experiment like this with OSweb:

practice_loop1 (sequence1) 4 trials

block_loop1 (sequence1) 50trials

practice_loop2 (sequence2) 4 trials

block_loop2 (sequence2)50trials

I want that the randomisation of the list of trials in block_loop1 is the same as block_loop2.

I think I have to do a Js inline to randomize the list of trials at the beginning of the experiment.

Does Anyone have any other suggestions?

Thanks,

Paolo

lvanderlinden

Hi @bilancino ,

Do I understand correctly that you do want trial order to be randomized between participants (but not within participants)? (If not, it sounds like you want to set the order of trials to sequential rather than *random*).

If you do want to randomize between participants, then yes, I think you should use some inline JavaScript. You could either

• Define the list of trial properties in an inline_javascript item at the beginning of your experiment
• Or define the properties of the first block like normal, in a block-loop item with order set to *random*, and append an inline_javascript item to collect the properties of the trials from the first block to store them in a list containing trial information for the second block.

Does this make sense? Please let us know if we could help you further. It helps when you upload your experiment here so that we can provide you with more targeted answers.

Cheers,

Lotje

bilancino

Thanks @lvanderlinden,

yes you understood correctly, the randomisation is between participants.

I used the in_line javascript AT the start of THE experiment and it's working properly.

Thanks,

Paolo