Can participants complete the experiment if sufficient credits have not been assigned?

URL of experiment:
https://moryscarter.com/vespr/pavlovia.php?folder=buchsbaumlab&experiment=memory_dynamictest_similarlures_exp2/

Description of the problem:
Hello,

I recruited 10 participants from Prolific, but only data from 1 participant was uploaded to Pavlovia. I have looked at other posts about data not being uploaded, but those solutions are not applicable to me.

I noticed, however, that there were 0 credits assigned to my experiment (it is possible that assigned credits were used up by a previous batch of participants). I’m confused because I see on Prolific that participants spent the expected 35m on the experiment. If an experiment does not have credits assigned, is it the case that participants are able to complete the experiment, but the data is just not uploaded? Can I have access to the data if I retroactively assign the credits?

Thank you,
Mrinmayi

PS: The experiment is hosted on Pavlovia. I’m using a different webapp to generate counterbalancing numbers. This is why the URL doesn’t start with run.pavlovia.

Hi @mrinmayik,

usually the experiment does not start if no credits are available. You can go to the credits tab of your dashboard and look up if credits were consumed for this experiment at the expected times. Then you at least know if the other nine participants also used up credits. I don’t think data can be accessed retrospectively. If it’s not in the project, it was not uploaded/recorded.

Thanks for your response! I hadn’t noticed the credits tab before.

Interestingly, it says that only one credit was used (and I have received data from 1 participant). I contacted the rest of the 9 participants and they said they were able to see the stimuli and complete the experiment, even though their credit has not been logged in Pavlovia, and their data is not available. Any idea what might be happening here?!

Thank you,
Mrinmayi

Did the time of their completion coincidentally fall into the time of this server outage (SERVICE OUTAGE: OVH servers appear to be down - #3 by jon)?

Otherwise, I have no idea. Do you see, if credits were reserved for the other nine?

Oh wow! That is possible. What is the time zone of the timestamp of that message (Sept 20, 7:54am)?

On the credits tab, I can see that credits were assigned to the experiment, and one credit was consumed. There is no other record for the time around which the experiment was started for the other participants.

I can certainly recruit more people to complete the experiment. But I have to pay the participants since they are completing the experiment on their end, even though I cannot access their data. So I’d really like to diagnose the problem!

Thank you for your help!
Mrinmayi

I don’t know. Where do you see this timestamp at all?

Edit: Found it. This post here has the timestamp Sep 21, 5:34 PM for me. This is my local time (GMT+2). Jon’s first post has the timestamp Sep 20, 1:54 PM for me. So I guess discourse always adjusts the timestamp to your local time…

Okay, then maybe the time of reserving is only saved for the credits that are consumed in the end.

Yes, I can totally understand that. I certainly don’t have the knowledge or competencies to give you further advice though :smiley:

Oh, in that case my participants didn’t coincide with the outage. :frowning:

Thanks for all your help! I’ll recruit a couple of more participants and see if the problem persists.

Hello,

I’m restarting this thread because I am noticing that participants are able to complete the experiment even if no credits are assigned (verified this by clicking the link myself while no credits were assigned - I was able to complete the experiment). When this happens, no data is recorded. However, because participants complete the study, we need to pay them (rightfully so!).

Why is the experiment still shown to participants even though no credits are assigned. Do we need to switch on some settings to ensure that participants get an error and are not able to complete the study when no credits are assigned to the experiment?

Thank you,
Mrinmayi

It shouldn’t be possible to start an experiment if it has no credits, unless you are covered by a licence (in which case data should be recorded unless you have an issue with your experiment (such as quit code in an end experiment tab).

You should also be able to stop participants doing your experiment by setting it to piloting or inactive, or by adding a routine at the start displaying some text (Thank you for your interest) but no keyboard or mouse response.

Please add me (Wake) as a developer if you’d like me to take a closer look.