Counterballanced Repeated Measure (separate sittings)


Author
Message
IOPsyc
IOPsyc
Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)Associate Member (184 reputation)
Group: Forum Members
Posts: 1, Visits: 1

Hi, I've searched the documentation and forum posts, but I'm still not sure whether this is possible. I'd like to use the web version to conduct my research:


I need my participants to complete a 60 likert-item survey twice, a week apart, under separate instructions. I also need to counterballance, so I'd like to randomly assign them to do either ExpA then ExpB or ExpB then ExpA. I'll ask the participants for the first couple of letters of their first and middle names, to match their responses under each condition.


Ideally, it would be great if I could get inquisit to first ask for the identifying characters: if not previously tested, then assign them randomly (alternating participants would suffice) to do ExpA or ExpB; if previously tested, direct to them to the Exp they did not do the first time.


I assume that this is probably a bit of pipe dream, so...


Alternatively, can I control how participants are assigned to each group, by sending separate web links for ExpA and ExpB (and without needing 2 licences)?



Thanks very much for any support you can provide,



Ben


Dave
Dave
Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)Supreme Being (829K reputation)
Group: Administrators
Posts: 10K, Visits: 57K

Hmm, I'd try with properly configured <batch> elements and a matching URL parameter.


<batch>
/ file = "ExpA.exp"
/ subjects = (1 of 2)
</batch>

<batch>
/ file = "ExpB.exp"
/ subjects = (2 of 2)
</batch>


I'd set up the launch page to assign subjects based on an URL parameter. Then, for phase one,  I'd send the first half of participants a link to the experiment with a parameter like group=1, the other half gets group=2. For phase two, particpants get the other group assigned. Seems viable, because the numerical subject is not the primary identifier in your case.


Hope this helps,


~Dave


GO

Merge Selected

Merge into selected topic...



Merge into merge target...



Merge into a specific topic ID...




Reading This Topic

Explore
Messages
Mentions
Search