| Reference | Downloads | Github

Data loss, empty log file

**used and tested on Win7 (initially programmed on macOS Mojave)
**PsychoPy version: 3.2.4
**Standard Standalone? Yes

Hi there,

in our study we created a Psychopy Experiment in the Builder which consists of a movie stimulus and several ratings before and afterwards. After we had six participants, we noticed that we lost some data and it is really hard for us to recapitulate what might have happened leading to the loss of data. Of course, we should have looked at the data immediately after the measurements but unfortunately we did not.

  1. In the first case it seems like psychopy only produced a completely blank log file and no psydat or csv file at all.
  2. In the second case we have (as usual) 3 output files (psydat, log and csv). These files include the routines, but no data entered by the participant. I recovered a new csv file from the psydat file but the data is also missing there.

Unfortunately, as we noticed this quite late, I don’t have any information on what could have went wrong from the experimenters’ side (like if a particular key has been pressed).

Could It be a problem, if esc is pressed on the last screen? We used to do this while testing the paradigm, but we never lost data even we actually defined that “e” should be pressed on the last screen to quit the experiment.

We present the paradigm full screen so the stop button (red cross) cannot have been pressed. We are currently running some tests and hope to replicate the error but so far we have not been successful, so if anyone has an idea what could be the problem, this would be very helpful.