Millisecond Forums

Error: Variable undefined...???

By pedrojose221 - 9/20/2013


I am using Inquisit Web to collect a second batch of data on Working Memory Capacity using the AOSPAN script provided by Inquisit. I have previously collected 20 participants' data for my study using Inquisit Web. The study is set up so that participants are redirected to Inquisit from qualtrics. I set up Inquisit to read URL parameters to match response ID's between surveys. My problem is this: After having closed the qualtrics survey (for adjustments to the study materials, and analysis), I reopened the study, but my participants receive an error when trying to take the Inquisit Web portion of the study. 

I should mention that when I tested it on my machine it worked just fine, so I'm not sure what the problem could be. Thankfully a participant was nice enough to send me a screenshot of the error:

I am not sure why this error is occurring, any insight is greatly appreciated, as my deadline-approaching thesis depends on this data...

Thank you in advance,


By Dave - 9/20/2013

The error suggests something's wrong with your launch page (e.g. an undefined variable). Likely you've changed something between the two waves. What exactly that mistake is, is impossible to tell without the link to the actual launch page as well as details on how you redirect folks from Qualtrics and which query parameters you are using.

By pedrojose221 - 9/20/2013

Thanks Dave,

The redirect occurs once participants finish a final test in Qualtrics. They are then automatically redirected to the landing page on Inquisit. Here's the link:

The parameters that are tagged on from Qualtrics are "condition" and "RID" so a sample of a URL redirecting participants from Qualtrics to Inquisit would look like this:

The changes I made were slight text modifications in the instructions, re-ordering of questions, and timing of certain slides in the presentation. Is it possible that one of the URL parameters being fed into Inquisit is missing?



By Dave - 9/20/2013

Thanks for providing those details. I can start the study just fine using those links, no error messages thrown whatsoever. Have you double-checked that Qualtrics is indeed forwarding participants as intended (including generating and forwarding the required query parameters)?

For example, if you do (note the missing value for the condition parameter)

you'll get the 'undefined' error. My best guess thus is: The problem is on the Qualtrics side, not Inquisit.

By pedrojose221 - 9/20/2013

I ran through the qualtrics survey and was able to do be redirected to Inquisit and take the AOSPAN task without any problems, I also looked at the URL and it contained the parameters I specified. I'm going to run more participants to see if the problem persists. In the meantime, if it helps any, here is the link to the Qualtrics survey:

If you decide to try it out, you can just click through the experiment without reading all the materials (should take less than 5 minutes to do that way). After which, you will be redirected to Inquisit and should encounter the same error that previous participants encountered. I appreciate your help in this.

By Dave - 9/20/2013

I ran through the Qualtrics survey and was redirected as expected with query parameters intact. No problems with launching Inquisit either (as expected). I do not know what's causing the issue for (some of?) your participants, but still my best guess remains a malformed query parameter as illustrated by the example in my previous reply. The Inquisit launch page does nothing except read those query parameters, it has no means to delete or change them, so the problem must be somewhere else (e.g. your subjects are behind a proxy that strips out query parameters or the like). In case you have implemented various conditions in the Qualtrics survey, consider the possibility that not all of them may be affected (e.g. redirection / query parameter forwarding may be broken only for the 1st condition).

I would recommend further testing and to direct people experiencing issue to copy the full URL from their browser's address bar and send that to you. Any missing query parameter values should be obvious there.