Lecture
Published Wednesday, March 08, 2006 by Mathieu.
Analysis and Design.
CLINTs and WIMPs
Command Line Interfaces.
Windows Icons, Mice, Pointing.
Most users will run from a CLINT.
Will voice bases systems take over? VR?
What is Human Computer interaction?
The ways and means by which humans use computers.
People think that computer users are chained to their computers.
This interaction is known as the user inferface.
The user interface is the "System"
If the user interface is poor, then the system is poor.
It's necessary, but not sufficient part of building a good system. You've seen lots of good looking programs that end up being a pain to use because they're not thought out.
People build models of how they think the world works.
Through experience, training and instruction.
These mental models are often wrong in principle, but correct in effect.
In Software Dev, we have three mental models.
The implementation
The System model
and the User's Model.
Which model should the system model match?
We're really concerned about what it looks like to the user. The implementor thinks too close to the technology even hardware.
Mental models are simpler than reality. Users come with models in their head from other softwares.
For many people, the screen and the keyboard IS the computer. In SOME cases, this is effective, even though incorrect.
People turn up their thermostats to heat up a room faster. This is in fact incorrect.
Example: The Baffling Case of the File System
The current file system is frustrating for users.
You have to understand how things are filed in computers. If you don't, you don't know why it is structured the way it is.
The real world analogy to using a file
Like using a book from a shelf.
We're actually burning the original book and relacing it. But we don't tell them that!
We've got military! We can solve military probs bys ending in the troops. But it's not a military problem, you cannot necessarily solve the problem.
You're guessing the problem.
The existence of two versions of the same document simultaneously is greatly confusing to some users.
So we want to make a solution in tune with the user's mental model.
What are the goals of a file system for the user?
...
So that's analysing the user requirements.
Saving changes to to the document
Nowadays, we can often save automatically. Save when the user stops, rather than when typing.
Etc all the other requirements.
"I've been using computers for 30 years, and I still find them very frustrating"
The need for design.
If you want good UI, you have to have the goal of making it good.
Just because it's good for you, doesn't mean it's good for everybody.
You can't design even for the average person.
People are variable enough for them to adapt to your design.
The UI is a part of its appearances and styling.
Design Principles.
Affordances
The percieved and actual properties that determine how something could / should be used.
The interface of a physical door.
Affordances are much more important than written labels. Pushed a door that was labeled "push" before?
If you make something that you need people to read the manual for, you're going to go broke.
Mental model awareness
Making things visible
System functions should be visible.
What DO the # and * mean? Nothing really. It just means that they're not numbers.
You'd need the manual to work out how to work it.
The button has no realtionship to the function.
People have far fewer problems in a foreign car than with their own telephone.
Visibility acts as a reminder.
People remember 3-7 things. If things are labeled, you don't have to remember them.
Mapping reflects the relationship between two things.
The steering wheel of a car.
Temperature coding to show rainfall rate.
Preattentative vision. The visual system spotts that you're being looked at. The human visual system is very quick as processing things.
People find reading pictures much easier than columns of information.
The principle of feedback.
This is sending info back the user on what action has actually been performed and what the result has been accomplished.
It needs to happen on time, if not, you need to know that it's all going to take a while.
So there we have the seven stages of action. Looks a bit like the recycling circle really.
CLINTs and WIMPs
Command Line Interfaces.
Windows Icons, Mice, Pointing.
Most users will run from a CLINT.
Will voice bases systems take over? VR?
What is Human Computer interaction?
The ways and means by which humans use computers.
People think that computer users are chained to their computers.
This interaction is known as the user inferface.
The user interface is the "System"
If the user interface is poor, then the system is poor.
It's necessary, but not sufficient part of building a good system. You've seen lots of good looking programs that end up being a pain to use because they're not thought out.
People build models of how they think the world works.
Through experience, training and instruction.
These mental models are often wrong in principle, but correct in effect.
In Software Dev, we have three mental models.
The implementation
The System model
and the User's Model.
Which model should the system model match?
We're really concerned about what it looks like to the user. The implementor thinks too close to the technology even hardware.
Mental models are simpler than reality. Users come with models in their head from other softwares.
For many people, the screen and the keyboard IS the computer. In SOME cases, this is effective, even though incorrect.
People turn up their thermostats to heat up a room faster. This is in fact incorrect.
Example: The Baffling Case of the File System
The current file system is frustrating for users.
You have to understand how things are filed in computers. If you don't, you don't know why it is structured the way it is.
The real world analogy to using a file
Like using a book from a shelf.
We're actually burning the original book and relacing it. But we don't tell them that!
We've got military! We can solve military probs bys ending in the troops. But it's not a military problem, you cannot necessarily solve the problem.
You're guessing the problem.
The existence of two versions of the same document simultaneously is greatly confusing to some users.
So we want to make a solution in tune with the user's mental model.
What are the goals of a file system for the user?
...
So that's analysing the user requirements.
Saving changes to to the document
Nowadays, we can often save automatically. Save when the user stops, rather than when typing.
Etc all the other requirements.
"I've been using computers for 30 years, and I still find them very frustrating"
The need for design.
If you want good UI, you have to have the goal of making it good.
Just because it's good for you, doesn't mean it's good for everybody.
You can't design even for the average person.
People are variable enough for them to adapt to your design.
The UI is a part of its appearances and styling.
Design Principles.
Affordances
The percieved and actual properties that determine how something could / should be used.
The interface of a physical door.
Affordances are much more important than written labels. Pushed a door that was labeled "push" before?
If you make something that you need people to read the manual for, you're going to go broke.
Mental model awareness
Making things visible
System functions should be visible.
What DO the # and * mean? Nothing really. It just means that they're not numbers.
You'd need the manual to work out how to work it.
The button has no realtionship to the function.
People have far fewer problems in a foreign car than with their own telephone.
Visibility acts as a reminder.
People remember 3-7 things. If things are labeled, you don't have to remember them.
Mapping reflects the relationship between two things.
The steering wheel of a car.
Temperature coding to show rainfall rate.
Preattentative vision. The visual system spotts that you're being looked at. The human visual system is very quick as processing things.
People find reading pictures much easier than columns of information.
The principle of feedback.
This is sending info back the user on what action has actually been performed and what the result has been accomplished.
It needs to happen on time, if not, you need to know that it's all going to take a while.
So there we have the seven stages of action. Looks a bit like the recycling circle really.