Information processing

In HCI there 3 main principles of information processing, human as a component, human information processing, and goals operators methods and selection rules.

Human as a component

The principle of human as a component is where people believe that part of a computer/HCI is the human, its the theory that humans are a component of a computer or HCI, because the human is apparently a main component of a HCI, HCI's have to be designed to meet the main components needs (the human). The most important thing to think about when creating an HCI is the humans who are going to be use it. The people designing an HCI have to think what the user wants from the HCI, and how do they want to interact with it. They also have to think about how they HCI is going to be used and what the user needs and required the HCI to do. The designers will also have to research to find out what the humans requirements are. Designers will also have to figure out how they have met the requirements, I would do this by getting humans to test the HCi.

Human information processing 

Human information processing is the principle which is a theory that humans work like computers do. People believe that the senses (hands, eyes, mouth & nose) are the input devices (this could be referred to as like a mouse or keyboard). The brain and mind are the central processing unit which thinks and calculates and produces something to output. The output devices are an action you perform using your body or an action you perform on a computer.

When humans are referred to as computers, they are both referred to as either more intelligent or less intelligent then computers.It is very hard to tell if humans are actually smarter then computer or not. Computers can deffinatly be seen as less lazy then humans. Computers only sleep when you tell them to, meaning that they can work 24/7. Computers do not get bored, they can perform basic and advanced calculations and deal with situations easily. Multi-core computers can perform more than one advanced calculation in a second then older computers, meaning that new computers are very efficient, especially with the release of Quad core and Hex core.  Humans on the other hand cannot perform as many tasks in a second as computers can. Humans also have better hearing, good image processing and we are very good at detecting anomalies. The main thing that computers don't have that humans do is common sense.

Overall I think that the question:  "Are humans smarter than computers?" is unanswered.

GOM's

GOM's stands for goals operators methods and selection. It is a specialist model that allows researchers and users to see what tasks are undertaken on a HCI and how the tasks are undertaken on an HCI.

Goals is what the user wants to do, what task do they want to complete? An example of a goal is saving on Microsoft office Word.

Operators is the physical movements and actions that need to be taken. An example of this is a click of a mouse.

Methods are the other methods the user can take to accomplish the task or goal they need to complete within the HCI. The best way to accomplish at task or goal is to use shortcut keys. 


Selections is the easiest and quickest way of accomplishing a task or goal within a HCI.The quickest way to reach a goal in a HCI is to use the shortcut key if there is one available. For example if you want to print in Microsoft Word, you can use the mouse to click on print, but the quickest way  is to use the shortcut key (CTRL+P). This is quicker then because it takes less time to do a short key command then using the mouse to navigate to the print button.

GOM's is quite unreliable because it does not predict users behaviour being affected by fatigue, social surroundings, or organizational factors.

When Designers use GOM's they have to account for errors, they can only do this by predicting where the errors are to occur, and predict the time it takes to correct the error.  

Predictive Models

There are 6 behaviour models that help HCI designers to predict the way an interface will behave, and if it is effective enough to be used on a computer or device. These 6 behaviour models are split into 2 catorgories, predictive and descriptive.

The predictive models are:

•  Keystroad-level model (KLM)
• Throughput (TP)
• Fitt's law

The discriptive models are:

• Key-action model 
• buxton's three state model 
• Guiard's model of bimanual skill 

I am going to look at 1 predictive model and one descriptive model. 

keystroke level model  (predictive model)


The keystroke level model was described by Card, Moran, and Newell in the early 1980s. The model focuses on how long it takes users to actually use the HCI via hardware. The keystroke level model features 11 steps that is used by individual people and organisations, they use this to estimate how long it takes to perform simple tasks involving the input of a human via hardware. Normally companies who cannot afford specialists use this method. 


The keystroke level model defines and measures how long it takes to press and release a key on the keyboard (measured in words per minute, and categorised into fast, novice and slow typists), how long it takes to point the mouse on the screen, how long it takes to press or release a mouse click, how long it takes to switch hardware devices, ie keyboard and mouse, how long it takes for the human brain to prepare to peform an action within an HCI, how long it takes to type a string of characters,how long the user has to wait for the system to perform the action in the HCI. 

The key-action model (KAM) (discriptive)

Computer keyboards today contain a vast array of buttons, the buttons are either symbol keys, executive keys, or modifier keys. Symbol keys deliver graphic symbols — typically, letters, numbers, or punctuation symbols — to an application such as a text editor. Executive keys invoke actions in the application or at the system-level or meta-level. Examples include ENTER, F1, or ESC. Modifier keys do not generate symbols or invoke actions, but, rather, set up a condition necessary to modify the effect of a subsequently pressed key. Examples include SHIFT or ALT. Basicly, this model looks at how users interact with HCI's using keyboards and what shortcut keys HCI's use.