Return to HCI page

Universal principles of design

1. chunking refers to how much people can remember. usually 4 +/- 1. example 5 words in a list.
1. should be applied to design when people need to recall and retain information
2. should not be applied when people need to scan or search information
2. five hat racks refers to the 5 ways you can orgainize information, regardless of application
1. alphabetical. example dictionary. good for referential.
2. time. example: historical timelines and TV guide schedules. good for comparing events over fixed sequences of time.
3. location. emergency exit maps. good for wayfinding.
4. continuum (magnitude). batting averages. good for comparing things that can be measured.
5. category (similarity). types of retail merchandise. good for ordering clusters of similar things.
3. garbage in – garbage out
1. problems of type: incorrect kind of input to system. affordances and constraints can help keep people from making these kinds of mistakes
2. problems of quality: type is correct, but actual information is incorrect (mistyping your phone number). previews and confirmations can help keep people from making these kinds of slips.
4. Gutenberg Diagram
1. related to “reading gravity”, people read from left to right, top to bottom. therefore they start top left, top right is a strong fallow area, bottom left is a week fallow area, and they end bottom right.
2. appropraite for information that is distributed evenly and relatively homogeneous.
5. Hierarchy of needs
1. function before creativity. hierarchy is as follows: function, reliability, usability, proficiency, creativity
6. mapping: a relationship between controls and their movements
1. effects that correspond with expectation are considered natural mappings
2. natural or good mapping is primarily a function of layout. if the controls are layed out similarly to the world (burners on an oven) then the mappings are natural.
3. avoid multiple effects from one control, and be careful when relying upon convention because different groups of people have different conventions.

Mullet and Sano

1. “common errors related to elegance and simplicity can usually be attributed to poor planning, poorly communicated structure, or attempts to go beyond the scope of a coherent, focused design. the inevitable result is visual or conceptual complexity and confusion.”
1. Clutter and visual noise
2. interference between competing elements
3. using explicit structure as a crutch
4. excessive detail and embellishment
5. gratuitous dimensionality
6. belaboring the obvious
7. overly literal translation
2. “because complex designs rarely seem elegant, simplification is an important step in the development of any elegant solution”
1. the most fundamental technique for simplification is reduction.
2. process for reduction:
1. “determine the essential qualities (typically a short list of adjectives) that should be conveyed by the design, along with any fixed formal elements, such as a name or label, an essential control, or a color, texture, pattern, or image
2. critically examine each element in the design and ask yourself why it is needed, how it relates to the essence of the design (identified above), and how the design would suffer without it. If you can't answer any of these questions, remove the element
3. try to remove the element from the design anyway. What happens? if the design collapses, either functionally or aesthetically, the element must be replaced. Otherwise consider omitting it from the final solution.”

Return to HCI page