Analyzing gaze tracking data

Question

I have an image which was shown to groups of people with different domain knowledge of its content. I than recorded gaze fixation data of them watching the image.

I now kind of want to compare the results of the two groups - so what I need to know is, if there is a correlation of the positions of the sampling data between the two groups or not.

I have the original image as well as the fixation coords. Do you have any good idea how to start analyzing the data?

It's more about the idea or the plan so you don't have to be too technical on that one.

Thanks

score 1 · Answer 1 · answered Sep 04 '11 at 21:53

1

Simple idea: render all the coordinates on the original image in a 'heat map' like way, one image for each group. You can then visually compare the images for correlation, and you have some nice graphics for in your paper.

There is something like the two-dimensional correlation coefficient. With software like R or Matlab you can do the number crunching for the correlation.

Matlab has a function for this:

Two Dimensional Correlation Function: corr2

Computes two dimensional correlation coefficient between two matrices and the matrices must be of the same size. r = corr2 (A,B)

answered Sep 04 '11 at 21:53

Daan

9,984
2
30
36

Thanks. That was also my first thought and I tried it using pearson's correlation coefficient. However, it should be robust against increasing numbers of images and I'm not quite sure how I could achieve this. Let's say you than have 4 images and want to compare the similarity of those in a "mathematically" way. Any idea how to this? – leroo Sep 04 '11 at 22:15
You probably should compare each pair of images with each group. When you add one image with data for a group, compare it with every other image and group. You can then aggregate the correlations to compare the groups. – Daan Sep 05 '11 at 06:53

score 0 · Answer 2 · edited May 23 '17 at 11:43

In gaze tracking, the most interesting data lies in two areas.

In where all people look, for that you can use the heat map Daan suggests. Make a heat map for all people, and heat maps for separate groups of people.
In when people look there. For that I would recommend you start by making heat maps as above, but for short time intervals starting from the time the picture was first shown. Again, for all people, and for the separate groups you have.

The resulting set of heat-maps, perhaps animated for the ones from the second point, should give you some pointers for further analysis.

Analyzing gaze tracking data

2 Answers2