CHAPTER 5 Flashcards
achieving goals within constraints
design
the purpose of the design we are intending to produce
goals
limitations on the design we are intending to produce
constrain
choosing which goals or constraint can be relaxed so that others can be met
trade off
the study and practice of usability on technology
Human Computer Technology
normative enterprises, where the process of peer review tends to encourage conformity to core set of values and approaches.
Scientific disciplines
provide designers with a series of tools and techniques for understanding social setting and organizing their observations to derive models for design.
Contextual Inquiry
provides set method whereby designers can move out from laboratory settings to the real world as a basis for design inspiration.
CI
Revolves around the features of an interactive system that allow novice users to understand how to use it at first and then how to attain a maximal level of performance .
to familiarize to a new system
Learnabilty
It makes use past knowledge of interacting with a similar system to ease the new system interaction
ability to know which action can be executed.
Predictability
the ability of the user to assess the effect of past operations on the current state
principle of honesty of user
Synthesizability
make use of new users past experience with other applications
familiarity
form of consistency
Users often try to extend their knowledge of specific interaction behaviour to situations that are similar but previously unknown.
Generalization
It relates to the similarities in behaviour arising from alike situations or alike task objects.
Consistency
refers to the diversity of ways which the user and the system exchange information
Flexibility
one of the ways to achieve dialog initiative is User-premptive , The user is the one to initiate an action on the system.
Dialog Initiative
ability to support more than one task of the user system dialog at a time.
Multithreading
Allows simultaneous communication of information concerning seperate tasks.
Concurrent Multithreading
Allows a temporal overlap between seperate task . but stipulates that at any given instant t;he communication is restricted to a single task.
Interleaved Multithreading
ability to transfer the control for the task execution between system and user.
Task Migratability
It requires that equivalent values can be substitute for each other
Substituvity
It refers to the modifiability of the user interface by the user or the system
Cutomizability
concerns itself with supporting the user in successfully accomplishing an action with the system
robustness
it allows the users to evaluate internal state of the system by means of its perceivable representation at the interface.
Observability
It allows the user to explore the current internal state of the system without modifying it.
browsability
assists the user by passive recall, such as suggesting the user possible words based on his text input.
default
allows the user to navigate through observable states.
reachability
This principle deals with the duration of an observable
state.
persistence
It covers the extent to which a system services support all of the tasks the user wishes to perform and in way that the user understands them.
Task Performance
It is the ability of a system to recover in case of an error. There are two directions in which recovery can occur, forward or backward
Recoverability
error recovery accepts that an error has occurred in the current state and negotiation from that state towards the desired state.
Forward
It deals with the time needed for the system to communicate with the user. In general, short durations and instantaneous response times are desirable.
Responsiveness-
covers the invariance of the duration for identical or similar computational resources
Response time stability
ensure that the system allows a user to perform task he needs and in an expecting way
Task conference
covers whether a system can perform all tasks of interest
task completeness
deals with the user ability to understand the tasks.
task adequacy
bodies to ensure compliance by a large community of designers standards require sound underlying theory and slowly changing technology
national or international
more common than software high authority and low level of detail.
hardware
offers a framework for reflecting debating and conversing within this challenging area, as well as documenting value that different types of design implications might serve
taxonomy
has points that need to be met for the success of a system, they are still suggestive and more guidelines
design rules
for usability relies on maximizing benefit one good design by abstracting out the general properties which can direct purposeful design.
repeatable design for usabiltity
