video being randomly skipped (case 6812)

[jarvis24]

Can you post a copy of your que file?

[ggcanna]

Thank you for your reply. Here it is.

[jarvis24]

Your input file looks fine. Can you also attach a zipped copy of an entire "data" folder from one of these machines so I can take a look at the output it's producing?

[ggcanna]

Here is the data collected from one of the computers. First video was skipped on subject 003, and both first and third video were missed on subject 016.

[jarvis24]

Oh, it's the probe data that is misssing, not the data from the regular medialab data files? In that case what may be happening is you have one probe running into another--this can happen if the probe durations can overlap and the subject does not respond to the first (or nth) before the next one (nth + 1). This can cause some chaos because the probe routine no longer know which probe is being responded to. I would have to see your probe input file to see, but that's my first hunch.

[ggcanna]

Hi, thanks again for your reply. I'm not sure though I quite understand what you said. The STRT data is the only data that's being collected throughout the videos, although we told our subjects that their primary task is to watch the video and secondary task is to respond to the beep tones whenever they hear one. We don't have a regular medialab data file. Also, I tried running the experiment on myself many times and if I missed a few beeps or ignored the STRT task altogether, later on the data file I saw "-1.00" values for whatever I missed rather than 0.00s, which seemed to be the values associated with the skipped video(s). I'm attaching the csv file here. Please let me know if you see anything wrong in it. Thank you!

[RCPRIME]

Hello,

I saw your post and was hoping you could help me. We're running an experiment in which people are watching commercials and responding to an auditory probe. The probes are working just fine but all of our data in the resulting probes.sav file shows up as -1 for the var_t, var_k, and var_r variables. We've tried different probe parameters with no success. We have changed the key instructed to be pressed from space bar to K?, but still no luck.

Were you able to find a solution during your experiment?

Russell