Millisecond Forums

Tabii eyetracker marker problem

https://forums.millisecond.com/Topic28253.aspx

By Willem - 2/11/2020

Hey everyone,

I'm having an issue with sending markers to the Tobii eye tracker data stream. Basically I want to send 3 different types of markers, indicating a fixation period, an information search period, and a feedback period. In total there are 15 trials (or rounds), so what I do is update several values during the experiment (for example, I set the marker of the first fixation period to 1001, while I set the information period of the same round to 2001, and in the next round I update it to 1002 and 2002, respectively). 

This has worked fine for me in the past, but with the current study it's not working. Some notable differences are that I use the openended type of trial and some branching logic that branches into a survey page. So a single round consists of a normal trial, followed by an openended response, followed by a branched survey page; all packed within a single block. I update the values at the start of each block, and insert the markers in the stimulusframes attribute of each trial type (trial, openended, and surveypage). 

The problem is that for some reason, I only see the markers of the fixation period (the first trial), but not those of the openended and survey pages. I've added the script to hopefully help resolve the problem (although it's quite a complicated script with many values being updated). The script I attach only works for participant number 1.

Hopefully someone can help!
By Dave - 2/11/2020

Willem - 2/11/2020
Hey everyone,

I'm having an issue with sending markers to the Tobii eye tracker data stream. Basically I want to send 3 different types of markers, indicating a fixation period, an information search period, and a feedback period. In total there are 15 trials (or rounds), so what I do is update several values during the experiment (for example, I set the marker of the first fixation period to 1001, while I set the information period of the same round to 2001, and in the next round I update it to 1002 and 2002, respectively). 

This has worked fine for me in the past, but with the current study it's not working. Some notable differences are that I use the openended type of trial and some branching logic that branches into a survey page. So a single round consists of a normal trial, followed by an openended response, followed by a branched survey page; all packed within a single block. I update the values at the start of each block, and insert the markers in the stimulusframes attribute of each trial type (trial, openended, and surveypage). 

The problem is that for some reason, I only see the markers of the fixation period (the first trial), but not those of the openended and survey pages. I've added the script to hopefully help resolve the problem (although it's quite a complicated script with many values being updated). The script I attach only works for participant number 1.

Hopefully someone can help!

If I am not mistaken, you need to enable /datastreams for the <openended> and <surveypage> elements. (Probably best to just set it at the block- or expt-level).

https://www.millisecond.com/support/docs/v5/html/language/attributes/datastreams.htm

By Willem - 2/12/2020

That was it! Thank you for the (as always) quick and helpful response, Dave.

P.S. I am having a lot of trouble writing these posts in Safari. Pressing Return makes the cursor disappear, and I can't place the cursor below a quote when replying. I tried to just edit the HTML, but that didn't go well either (see previous post).