On Apr 20, 2008, at 7:45 PM, Paul Nuschke wrote: > Imagine that a user needs to click on a link to go somewhere. If she > fixates > on the link and don't click it, then that's pretty good evidence > that she > did not understand the link.
All you know is that the eye tracker registered that they fixated on the link and that they didn't click. The notion that they didn't understand the link is one inference. It's not the only inference. It may not be the right inference. It is purely *your* interpretation that the user didn't understand it. (And you could've gotten there without the eye tracking data.) >> We know that people see things through their peripheral vision, such >> as the scroll bar, so that's not recorded by the eye tracker. That >> means we can't even assume that when someone doesn't gaze at a spot >> that it wasn't seen. > > True, but that's a good thing. You can't read or see fine details in > your > peripheral vision, so even if you notice something it doesn't mean > that you > looked at it enough to understand what it contained (unless the > important > details were very big). Again. Your inference. You don't have any evidence to actually know that's true. In fact, in psychographic phenomena, it's pretty amazing what people can see and deduce from the peripheral vision. There's a lot happening within 140 degrees of the focal point. And it's pretty amazing what is lost within the center gaze area, especially with people who have field issues that are frequent in males over 40, females over 50, and anyone suffering from optic neuritis or other immune-deficiency-based symptoms. (In MS patients, for example, optic neuritis frequently shows up in late teens, early 20s.) So, you are just inferring meaning to the data you're collecting. > In the example above, even if the user noticed that > a link existed, if she did not attend to it, then she would not have > been > able to read it. Your inference. There are other likely inferences too. >> Show me a study that shows that N separate evaluators looked at the >> same eye tracking data and came away with the same conclusions and >> I'll change my mind. > > That some data does not make sense is not a phenomenon unique to > eyetracking. I've seen plenty of different interpretations of > statistics as > well. Ok. Does that make eyetracking work? Not buying it. Still think it's up to the interpreter of the eye tracker. Let me put it another way: Would you, Paul, be comfortable letting your clients to use the eye tracker without any help in interpreting data from you. Is the device all they need to make the judgments necessary to provide good design advice? Jared Jared M. Spool User Interface Engineering 510 Turnpike St., Suite 102, North Andover, MA 01845 e: [EMAIL PROTECTED] p: +1 978 327 5561 http://uie.com Blog: http://uie.com/brainsparks ________________________________________________________________ Welcome to the Interaction Design Association (IxDA)! To post to this list ....... [EMAIL PROTECTED] Unsubscribe ................ http://www.ixda.org/unsubscribe List Guidelines ............ http://www.ixda.org/guidelines List Help .................. http://www.ixda.org/help
