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Connection timed out (errors starting task) / errors saving data

URL of experiment: [study is currently in progress - we can add the link at a later date or duplicate the repository if needed]

Description of the problem: We designed a long task (30+ minutes) which records mouse position data on most trials. Is there any chance that Pavlovia online servers would have trouble with that amount of data when multiple participants attempt to complete the study?

When the task was released to more than 15 people at a time (via Prolific), there were some errors. We have not been able to obtain exact error messages from many of the participants, but we did receive one, pasted first below (which I believe occurred when starting the task). There was also at least one error that occurred after the task, and a corresponding message from a participant is pasted second below.

Here is one error message:
"The connection has timed out

The server at is taking too long to respond.

The site could be temporarily unavailable or too busy. Try again in a few moments.
If you are unable to load any pages, check your computer’s network connection.
If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web."

Here is a message from a participant:
“Hello, when I was finished …, an error message popped up that it hadn’t recorded the data and something went wrong.”

As far as I know - this should not be an issue. Did the participant report having a stable internet connection?

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No one has provided information about a stable or unstable internet connection (but that doesn’t mean much - we’ve had trouble getting information from the participants). Scrolling through the messages, one of the errors that occurred after the task was complete involved a message: “submission failed”.

Apologies for the lack of information. I’ve never been able to replicate these errors myself; perhaps there is an internet connection issue on the participants’ end at the beginning or the end of the task. If there is an unstable connection, could that result in inability to load the task or a failure to submit after completion?

No need to apologies - sometimes we can’t anticipate these things until they are “in the wild”!

Yes, internet connection is vital at the beginning and end of the task. If it is slow at the start the experimetn resources might just take a long time to load, but if it is unstable at the end that can result in data not getting sent back to pavlovia, sadly. If internet connection is unstable during then that isn’t really an issue, since all resources were loaded at the start of the task (so it wouldn’t slow down the stim presentation or anything).

I would recommend emphasising the internet connection if you can? In particular also emphasise waiting for the green thankyou message at the end.

Thanks, we’ll try to add some words on the next go to make sure participants are aware of the importance of the stable internet connection (especially “wait for the green thank you message at the end”). I would be surprised if an unstable connection was responsible for all of the errors, but hopefully that will help with some.

Yes, please keep us posted we’ll do what we can to help!
Hopefully that avoids some of the issues though!

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