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Minor update to Procrastato, download version 0.6.1

Ben FranklinI’ve made a very small update to Procrastato, the only Firefox extension that will get you back on track when you are procrastinating. Really I just cleaned up some extra files that didn’t need to be included in the install.

Please head to the main project page to download and install the latest version.

As always, any comments or questions you have are welcome.

Procrastato Update 0.6

I have updated my Firefox Extension, Procrastato.  In addition to some small fixes, there’s a new ‘helpful’ mode.  While in helpful mode, you’ll get sage advice from Benjamin Franklin rather than the cold, hard stare of Big Brother.

Go the the main page and check it out.  I’ve also added it to addons.mozilla.org, but it is still in the sandbox so you’ll need an account to download it.

Here’s a screenshot of Ben in action:

Ben Franklin says get back to work

Formal usability testing with eye tracking – Mealographer

Usability Testing

Usability tests can be seen to fall into two general categories, based on their aim: tests which aim to find usability problems with a specific site, and tests which aim to prove or disprove a hypothesis. This test would fall into the former category. A search of the literature will reveal that tests looking to uncover specific usability problems often use a very small number of participants, coming from Nielsen’s (2000) conclusion that five users is enough to find 85 percent of all usability problems. Nielsen derived this formula from earlier work (Nielsen and Landauer, 1993). Although there is much disagreement (Spool and Schroeder, 2001), this rule of thumb has the advantage of fitting the time and money budget of many projects.

Use of Eye-Tracking Data

In terms of raw data, eye tracking produces an embarrassment of riches. A text export of one test of Mealographer yielded roughly 25 megabytes of data. There are a number of different ways eye tracking data can be interpreted, and the measures can be grouped into measures of search and measures of processing or concentration (Goldberg and Kotval, 1999):

Measures of search:

  • Scan path length and duration
  • Convex hull area, for example the size of a circle enclosing the scan path
  • Spatial density of the scan path.
  • Transition matrix, or the number of movements between two areas of interest
  • Number of saccades, or sizable eye movements between fixations
  • Saccadic amplitude

Measures of processing:

  • Number of Fixations
  • Fixation duration
  • Fixation/saccade ratio

In general, longer, less direct scan paths indicate poor representation (such as bad label text) and confusing layout, and a higher number of fixations and longer fixation duration may indicate that users are having a hard time extracting the information they need (Renshaw, Finlay, Tyfa, and Ward, 2004). Usability studies employing eye tracking data may employ measures that are context-independent such as fixations, fixation durations, total dwell times, and saccadic amplitudes as well as screen position-dependent measures such as dwell time within areas of interest (Goldberg, Stimson, Lewenstein, Scott, and Wichansky, 2002).

Because of the time frame of this investigation, the nature of the study tasks, and the researcher’s inexperience with eye tracking hardware and software, eye tracking data was compiled into “heat maps” based on the number and distribution of fixations. These heat maps are interpreted as a qualitative measure.

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