15 - 07 - 2004
New Uzilla Component: Obzerver
The Obzerver module
provides an open source implementation of a click
stream monitor. It writes log files to the local hard drive in
Mozilla Firefox and the Mozilla suite.
The stored data is in the FLUD format
, proposed by NIST in 2002:
loghead 2004/6/15-8:55:39 subject=100 version=v1 time_zone=-5 generator=obzerver
event 2004/7/15-8:55:40.401 1:0
#OP newpage complete
This FLUD sample shows only the page level data. Low level event
data is also partially complete but not yet integrated with logging.
The FLUD format calls for identifying the sources of navigation
elements and in the web scenario might allow us to quantify the
relative proportions of methods for accessing new content.
C.Soules (a CMU CompSci grad student) crafted the Obzerver
implementation and is interested in the source events for a different
reason; for the meta data they provide.
is ready for use today for simple url logging and with a bit
more effort for more complete event traces. The Uzilla.net suite
provides these rich event traces, a way to model your test protocol,
and data analysis.
If you're interested in helping with the project, check the out the bug list
Commenting on bugs and filing new ones is a great way to start getting
involved. For a meta-view on how this works, check the working paper Usability Discussions in Open Source
Posted at 8:58
24 - 06 - 2004
A Better Multi-Select Widget: Open Source DHTML
In a recent usability study, we observed that the intranet user base was
unfamiliar with the convention of control-click
for selecting multiple
options in an HTML menulist widget.
To address this issue, we used checkboxes and DHTML to eliminates the need to control-click to select multiple
items. In addition to creating an affordance multiple selection, this
system also provides better system status information.
An example is shown below in which the user has already selected
two options from the first two collections and is working on the third:
The design saves clicks and screen real esate by making the checkbox
The code is available as open source using the business friendly MPL license. More information, a live demo, and the source.
Posted at 16:33
27 - 04 - 2004
13 - 02 - 2004
Analyzing Usability Quantitatively
Jeff Sauro's site measuring usability .com
is a great introduction into the issues and rewards of quantitatively
measuring usability. Articles expound upon the intracies of task timing
, task order randomization
, and a fresh approach to thinking about sample size
Based upon a initial reading, these articles all express themes in line
with the design rationale of Uzilla.net. For instance, Uzilla.net allows partialing
out page load time, supports task order randomization, and of course,
by easing the preparation and analysis phases, enables a greater number
Posted at 10:34, Published in: Testing
12 - 01 - 2004
Open Source Credits and Related Resources
Two new pages, works in progress, offer credits
to open source code and related public resources utilized in Uzilla as well as code contributed back to open source. The related tools
page points to other resources for web developers and user experience professionals.
Posted at 21:17
01 - 12 - 2003
Macintosh OS X for Usability Professionals?
OS X is very popular among internet developers and designers, with the
availability of Macromedia and Adobe tools. Is OS X a reasonable
choice for a usability professional?
Uzilla, LLC's tools, the browser-based usability testing suite
, and uzCardSort
all work on OS X. UsersFirst
has recently introduced a video capture system that requires a mac laptop. MacSHAPA
, a longstanding video analysis tool, is coming to OS X.
Hmm, a g5
or a tiBook
Posted at 13:15
17 - 11 - 2003
Quantifying Lost in Hyperspace
Smith (1996) proposed a measure of "lostness" in hypertext structures
that centers around page revisits. The lostness measure shown
below, from a data table from the Uzilla.net reporting application ,
depicts the most lost users in a recent test.
by lostness ascending, the pictured users exhibit
high rates of page revisitation which Smith argues indicates the users
are lost. Efficiency on the other hand takes into account
redundant page views, but also deals with the total number of page
views versus the minimal (or "optimal") number. The two measures
are correlated but not perfectly, as users with the same lostness may
vary in efficiency.
Lower values of lostness indicate more confusion and lower values of efficiency are better.
We're not totally convinced this measure captures negative user
experiences in all cases. Certainly, in a shopping scenario a
user might revisit a product page repeatedly while comparing it to
other options -- and that's a desirable business outcome. In other
applications, revisitation may be a clear indicator of confusion.
We'll report on correlations between this measure of confusion and other measures we've been cultivating in the coming months.
Smith, P.A.: Towards a practical measure of hypertext usability. Interacting with Computers 8 (4) (1996) pp. 365-381
Posted at 0:2, Published in: Web Usability
08 - 11 - 2003
Variations on Remote Usability Testing
The latest IBM Systems Journal features a nice writeup titled "Methodology for remote usability activities: A case study"
. F.S.H. Krauss classifies remote usability activity into four categories:
- real-time design walk-throughs and usability tests
- automated usage tracking
- handling of user-reported critical incidents
Number 4, user reported critical incidents, is the least explored
in commercial settings but was one of the earliest uses of the phrase
"remote usability testing" (Hartson, 1998
The IBM article re-affirms the cost savings of remote testing and
expresses value in moderated remote tests and usability focused
surveys. Issues of firewalls and participant bandwidth are paramount,
but the general conclusion is that the approach is of value.
Uzilla has additional tools for real time remote moderation in development. Look for an announcement in the coming months.
Posted at 10:25
04 - 11 - 2003
Card Sorting Developments
Uzilla, LLC's open source card sorting tool
is now documented, and supports an export of similarity matrix for analysis in external applications.
We've had some interesting conversations recently and a spec for hierarchical sorts is underway using a zooming metaphor. Lou Rosenfield
asked if it supports open and closed sorts -- of course! For
clarification, this means you can pre-specify the target categories or
allow the user to make them up. Heck, you can even do a mix of
Posted at 15:52, Published in: CardSort
06 - 10 - 2003
Advanced Search, well done.
NPR's advanced search for the audio archives is very well done:
The use of an inline descriptor for the keyword box serves to conserve
valuable real estate, easing the impression of effort associated with
completing the task. The first drop down offers a concise set of
time periods, growing in range as they get further from the current
time. The key design feature is an understanding of the user's
task, resulting in filters which reflect previous experience.
A little birdie told me that NPR's site is soon to undergo it's first
major redesign. Keep an eye out, it's sure to make a great
resource even more useful.
Posted at 20:52, Published in: Web Usability Design