HCI Assignment 2
Assignment 2
Perception
Perception varies between the developer and the end user.
The end user might not be aware of the importance of the colours or the
positioning of the GUI on a desktop. The developer who makes the GUI may not
design it, or not the one who interviewed the client. Also the client may not
be and won’t fully represent the end user, so their perceptions may differ. Perception
is important because it gives the developer a sense of what the end user needs
are for the interface.
Colour
When designers design HCIs, then the most important factor
that the designer has to focus on is colour. For example over the years
Microsoft have made whole lot of changes to the colour in Word. In 2003,
Microsoft Word had a grey background but in Microsoft Word 2013 they have a white
background. This background makes it look fresh to the end user. Also some end
users may get affected more by certain colours. For example a person with
Dyslexia can see words more easily on pink or yellow paper. Colours are
important because it makes other objects on the screen stand out more.
Pattern
Patterns usually refers to the picture on the GUI or its
layout (template). For example Microsoft uses a layout for their dialogue
boxes. This will may the layout consistent and symmetric. This can aid the end
user because of its user friendliness and connectedness. Connectedness means
the ease and familiarity with which users move from one location to another,
such as between windows or applications. Patterns are important because it
makes the end user feel comfortable and confident with what is going to happen.
Layouts may include colour, format, layout and common groupings (including
menus and options).
Objects
All components in GUI or any other form of an image are
built using separate objects. It is essential to identify which images appear
first and which overlay the first. Overlay windows appear in the correct
overlay order. A GUI must also fit the screen and not overrun the boundaries of
the window as will hide some of the features. These are important because
object give us an organised window to work
Behaviour Models
Behaviour deals with the way users behave on interfaces e.g.
how fast it takes for them to move the mouse and click a button. These are important because it shows the
designer what will be the most efficient interface would be for the end user.
Predictive Models
Predictive models predict the way in which an interface or a
user would behave. There’s number of different models that provide a lot of
guidance into designing interfaces and systems. This is important because with predictive
models you can pre-empt what will happen without a load of research and delay
the implantation.
Descriptive Models
There are two main types of descriptive models:
·
The key-action model (KAM) – KAM identifies the
need to evaluate how the user will expect the computer to behave or react and
how the computer actually reacts to commands. For example some who is new to
computers will find logging into a computer a very difficult task to understand
the reason to typing a username and password accurately, or cannot log on.
·
Buxton’s three state model – Buxton’s three
state model deals with the pressure and dexterity with how users make movement
with mice, pointers and touchpads. For example an interface will need to be
responsive whether it is commanded via mouse, a touchpad or the roller but on a
keyboard.
Humans as a component
Humans as a component looks at what human’s needs and
expectations are. To do this HCI designers can carry out testing and risk
assessments to get this information. For example if a user selects one option
before another then what happens. Humans show many things while interacting
with a computer like emotions, intuition, cultural differences, language,
motivation, senses and physical limitations, problem solving ability and
learning. This is important because if a designer calculates how long it takes
the human brain to calculate data because that way, they can create a HCI which
is a lot faster and can process thousands of data every second.
Human Information Processing (HIP)
HIP is the way in which us humans absorb information,
analyse it, use it and do something with it. Our brains can be compare with
hardware of a computer because they take the information, then use the software
(the mind) to process it. The output can be depended on what our previous
knowledge is and how we process this past knowledge. Information processing is
the change in a state of information. This allows us to split this information
down into four steps that can be easily read and understood by us humans. The
steps are:
- Absorb the information
- Analyse the information
- Use the information
- Do something with the information
HIP is important because we can make computers much faster
by comparing them with humans. For example multi-core computers can perform
more than one advanced calculation in a second than older computers. Humans on
the other hand cannot perform some of the tasks in which computers do but they
are better at hearing, image processing and we are very good at detecting
anomalies.
GOMS (Goals, Operators, Methods and Selection)
GOMS are models that can predict the time it will take for
action to be carried out or a command to be followed. For example there are a
number of ways in which we can save our work in Microsoft Word, we can go to
file and click save or press a keystroke. When designer’s use this models
they’ll need to identify what the goals are of the intended action. This can be
a series of operators and lists the method in which we carry out that action
like mouse and keystrokes. This allows
the designer to calculate the time it takes for us to do that mouse movement or
keystroke. Once the designer has the results it can then identify which method
is more reliable, efficient and easy for the end user to use, based on the
user’s requirements. GOMS are important because it allows us to predict the
time it takes for us to do a command. This allows designers to make a more
reliable interface for the end user.
