Tuesday, 6 March 2012

Information processing models

Information processing models is another fundamental principle of HCI and is all about how people think to do this designers have to think what if the user selects one thing before another. Computers are like brains because they both take in information then analyse the information then uses the information.









•It is important to have the users attention so you should create an interface which isn’t too hard to navigate, make sure there isn’t too much or too little information, you should use groupings, you should place objects in way where the user can get good information.
•People can recognize material so much faster and much more material than they can recall it.




•Recognition: knowledge in the world.
•Recall: knowledge in the head. 
  
Some selections need to be made when creating an application like what audience you are aiming for.
The goals of your application has to be considered like if it is for educational or other purposes
The people operating the application have to be taken into account such as will they need anything to help them navigate.
 Some methods which may be use in information processing are keeping things as simple as possible for the user to navigate, keeping the layout the same throughout, use a lot of diagrams, use sound.
 •The reasons these methods should be implemented is you will cover most the ways in which people learn through.

Behavioural models

Behavioural models is another fundamental principle of HCI and is all about predicting possible impacts of systems or interfaces. It is also about the reaction time of a person using a GUI.
 
 
 
 


  A Key stroke module is used to determine how long it takes to do a simple task.
Throughput is the amount of work that can be preformed by a system component in a given amount of time.

 
Fitts’ law is where someone can predict how long it would take to rapidly move from the starting position to the final area.
There is no average user we are all different with different skills. The age of someone can cause a problem because as people age they become slower and can’t do things as fast. The cultural differences can cause a problem because people will use things differently.
Guiard’s module of bimanual skill is all about having something for right and left handed people.
The Key-Action Module is all about how quickly people can press a key on the keyboard.
Buxton’s three state module is all about different ways the mouse is used on a computer.



Perception

Perception is a fundamental principle of HCI and is all about how someone sees something. A user may not be able to see very fine details e.g. A GUI. In a GUI the importance of colour can be overlooked by the user or the position of the GUI on the screen can be overlooked.
These parts allow the user to  have easier access to things. In the image can you see a rabbit, or a duck, or can you see both?

Not everyone has the same vision, some have colour blindness  (only certain colours). You must be careful about what colours you put on a background or it could cause problem you should mainly avoid putting red on blue, yellow on blue, red on green  or  yellow on blue.
People from different countries can perceive colours differently but colours we associate for different states of things could be  Green for normal or OK, Orange for caution, Red for problem.
A trichromatic system is a theory which goes about the idea that your visual system can maximally see three colours and that other colours are seen through combinations of the three colours
Luminance is about light passing through (or being emitted from) an object.
‘Pop out’ effect is about having an image and editing the colours to where they look like they are coming out of the screen.



 There are a few laws of perception:
Law of proximity- This laws is all about how we perceive things when they are close together.

Law of similarity- This law is all about how the same shapes come together in our minds.

Law of symmetry- This law is all about how the rest of a shape can come together with only a small amount of that shape.

Law of closure- This law is all about being able to see shapes or letters without them being complete.

Law of continuity- This law is all about having a colour or a button running throughout a whole presentation.

Law of common groupings- This law is all about when people see a set of things that are similar and put them into a group together.

Law of connectedness- This law is all about when two objects look like they fit together to make a whole object.


Geons are 2D images which are going to be turned into 3D images so they are easy to recognise. These shapes aren’t expensive to produce.


Gross 3D shapes are shapes which are 3D and these are mainly used In video games. These shapes aren’t expensive to produce.