Define usability testing
Usability is all about how easy a product,
service or system is to use.
The extent to which a product can be used
by specified users to achieve specified
goals with effectiveness, efficiency and
satisfaction in a specified context of use
(ISO 9241-11 )
Approaches to measure usability
Effectiveness
the accuracy and completeness with which users
can achieve their goals
Efficiency
user's ability to quickly accomplish tasks with ease
and without frustration
Satisfaction
how much a user enjoys using the product
Approaches to measure usability
Type of Data
Performance data
Successful completion rates, Number of click while
performing a task, etc..
Preference data
User comments from questionnaire or interview
Satisfaction rates
Method
User testing
Surveys/questionnaires
Test Environment
Usability testing can be conducted extend from business
or office applications through to environment specific
systems.
Test environment facilities vary greatly in capabilities,
flexibility, and cost.
For business or office applications
Fixed labs
Adjacent rooms, video monitors, video recorders, computer
equipment, etc…
Portable labs:
Similar capabilities
Can be readily shipped and set up quickly
Test Environment
For environment specific systems
Flight simulator
A typical example, pilot would be recreating with
flight simulator and testing a new cockpit interface
to see if it matches their mental models.
Osmose
a Head-Mounted Display (HMD)-based, stationary,
virtual reality system.
Scripted or Unscripted Testing
Scripted
Scripted tests are written to persist for the life
of the product, and may be automated with
test execution tools to run frequently and in
bulk throughout the life of the product.
Unscripted
Unscripted usability testing is a more informal
testing comparing to the formal scripted one
but with higher flexibility.
Scripted vs Unscripted
Scripted
Persistent
reviewed in advance
Repeatable
Test automation
Unscripted
Less preparation
intellectually stimulating
deductive reasoning based on the results
Test labs
UserWorks Inc.
offers several portable usability labs for sale or rent
observational data logging software product
Usability Labs by Lodestone Research LLC
state of the art audio & visual recording and testing
equip.
designed to be portable
Purposefully built test room & observation room
User Audience
Select participants represent true users
Locating the right people & persuading
them to commit time
Key characteristics to be considered
New vs. Returning Users
Gender, Age, Education, Etc
Web Savvy
Captive Audience
How to engage
Three stages of recruitment
Before the sessions begin:
Developing a target user profile
Using rigor in defining screening criteria
During actual recruiting
Recruiting “backups” to handle “no-shows”
Recognizing possible technology spies or competitors
After the sessions begin
Dealing with unsuitable participants
Understanding why a “good” participant might not be, and
why a difficult one is valuable
System Compatibility
Whether hardware, software, websites and
applications work as expected with the range of
systems and components available to end users
Factors can be considered in web design as:
Web browsers
Various operation systems
Screen resolutions in web browsing
Technique used in website