user experience metrics Flashcards
what is the point of user experience metrics
allows you to improve and compare designs
can assess whether your product is better than the competition
what do ux metrics measure
usability utility ux
what are some criteria for usability
efficiency
effectiveness
satisfaction
learnability
memorability
errors
learnability
how easy it is to complete goals during first time use
memorability
how easy is it to continue using the system when you haven’t used it in a while
effectiveness
how well and completely users can achieve their goals
efficiency
the time and effort required to achieve goals
satisfaction
how users feel about the experience
errors
how many how sever and are they easily recoverable
usability metrics
measurements taken relative to user performed tasks
what are 4 usability metrics
success rate
time taken
error rate
user subjective satisfaction
performance measures
task based and relies on clearly defined criteria
learning curve
describes how performance of SKILLED BEHAVIOUR increases with practice
4 basic metrics of performance measures
task success
errors
time on task
clicks/actions
task success
measures effectiveness with a clear pass and fail criterea
task success rate
% of users who succeed
eg of pass fail criteria
giving up
moderator calls it
timeout
completed but wrong
errors
event based can be counted
have to decide what counts as an error
e.g. of something that could count as an error
wrong choice
key action not taken
data entry error
error rate
average number of errors per task
time on task
measures efficiency with a defined start and stop
has variations so should conduct multiple trials and get an average
clicks/actions
measures efficiency via the effort needed to complete a task
can compare the number of actions taken vs the minimum actions required
user reported measures
provide quantitative feedback via standardised questionnaires and rating scales
post task questionnaires
rate experience after each task to compare tasks
post test questionnaires
rate the experience after completing all tasks in the system in order to compare systems
what is an example of a post task questionnaires
single ease question(seq); has a rating scale
what is an example of a post test questionnaires
system usability scale(sus); 10 statements with a scale then combined to make a sus score out of 100
levels of measurement
the relationship amongst attributes
variable
anything measured in a study
attribute
a possible value of a variable
what are the 4 levels of measurement
nominal
ordinal
interval
ratio
norminal
attributes have names but no relationships
ordinal
attributes are ordered
interval
distance between possible values is meaningful
ratio
ratios are meaningful
