1. User Interface Engineering
Usability Lifecycle by UIE
Rupert Kiefl, Markus Meichau, Tobias Schraut, Denise Unfried
Introduction
The usability lifecycle is applied by UIE as a method to improve user interfaces for software applications. It accompanies a series of productive releases.
Evaluation based on participation of users is the main driving force behind the lifecycle.
No matter how carefully an interface is designed by usability experts, evaluation with real working tasks performed by users are essential to meet
requirements of an interface’s productive use.
Feedback Analysis (User Interface Evaluation)
Applied Methods Applied Methods
‘Expert Interviews’ ‘Thinking Aloud’
If a new interface is required and insight into domain specific requirements is necessary, this Interface releases are tested together with potential users from institutes of the Max Planck
method can help starting from scratch with a new prototype approach. Society. They perform tasks covering important application functionality. An interviewer tracks
Expert interviews help reveal the mental model and domain specific perspective behind user feedback and observes user interactions. All issues are noted down. The test result is
interactions. accumulated if at least 8―11 interviews are performed. An analysis (Figures 6,7) is given at
the end of the interview series, which leads to measures and changes in the interface.
Results from Expert Interviews conducted in Results from analysis of usability interviews
Garching and Munich 11 Interviews for PubMan Release 2 (MPG Harnack House,
The design of easy submission is based on expert MPI for Psycholinguistics)
interviews. Different approaches were collected
analyzed and compared (Figure 1). The result was first 9 Interviews for PubMan Release 3 (MPI of
implemented in R3, proven and is now in place for R5. Molecular Plant Physiology, MPI for
Gravitational Physics, MPI for Human
Development)
Figure 1: Layers of a pattern architecture
‘Personas’
Personas provide a clear picture of the audience the interface targets. It reveals their Figure 6: Figure 7:
skills, experience, limitations and work environment. The data then shape a virtual person Evaluation Analyses of R4 Evaluation Analyses of R2
representing the ‘average user’* of the web application.
‘Heat Maps’
Heat maps show where users try to interact (Figure
Personas for Publication Management 8). The example depicts an implementation of the
The image depicts three personas relevant for Publication Management inside the MPS. open source solution ‘ClickHeat’. The results were
not considered, as the PubMan layout changes
dynamically and mouse clicks couldn’t be tracked as
Figure 8: Heat map evaluation precisely as needed.
Prototyping
User Interface Prototyping
Before implementation starts, an interface is first shaped
by rapid prototyping (Figure 9) with a prototype
application. Prototyping reveals a lot of questions to be
answered either by functional specification
implementation design or interaction. It saves interface
development from tedious and time consuming trial and
error approaches.
Prototypes are very close to the application and can
Figure 2: Personas
even be tested with users before development starts.
* All important figures are collected from usability interviews, ranging from age to professional background and education.
Results of Prototyping
All interfaces for publication management (R2–R5) and
other Solutions are available as prototypes. Figure 9: PubMan Prototype
Release: ‘e.g. Easy Submission’ Development
GUI Accessibility & Constraints
2007 2008 2009
(R1) (R3) (R4) After the team UIE was introduced, it
immediately started working on existing
interfaces (GUI V1). In parallel, a GUI pattern
library, based on reusable components was
prepared to replace all existing interfaces
(GUI V2).
For all new interfaces accessibility
Figure 5: requirements and GUI constraints were set
‘Easy Submission’ (GUI V2)
Figure 4: up and documented.
‘Easy Submission’ (GUI V1)
V2 GUIs degrade gracefully if no JavaScript
is available or non standard conform
browsers are used. Color and contrast vision
deficiency is taken into account as well by a
set of color schemes.
Figure 3:
‘Edit Item’ (Start Interface Engineering)
Figure 10: BITV Requirements
Rupert Kiefl, Markus Meichau, Tobias Schraut, Denise Unfried
Max Planck Digital Library · Amalienstrasse 33 · 80799 München · www.mpdl.mpg.de July 2009, Licenced under Creative Commons­License BY NC SA