HF Midterm v4

Question 1

1 80/20 Rule

Answer 1

A high percentage of effects in any large system are caused by a low percentage of variables.

Question 2

2 Accessibility

Answer 2

Objects and environments should be designed to be usable. without modification. by as many people as possible.

Question 3

3 Advance Organizer

Answer 3

An instructional that helps people understand information in terms of what they already know.

Question 4

4 Aesthetic Usability Effect

Answer 4

the degree to which system usability is affected by visual. aural. tactile. olfactory. and gustatory aesthetics. Pleasing to the eye.

Question 5

5 Affordance

Answer 5

a property in which the physical characteristics of an interface influences functionality. Think of Affordance as the degree to which behavior or usage is solicited. 88 An invitation to provide you with the opportunity to use the system. IT MAKES IT EASY TO USE. 88 It is inviting you to use it. 88 A sure indicator of a poor design is something that has lots of instructions.

Question 6

6 Alignment

Answer 6

The placement of elements such that edges line up along common rows or columns. or their bodies along a common center.

Question 7

7 Archetypes

Answer 7

Universal patterns of theme and form resulting from innate biases or dispositions. Note this is probably more common in human factors designs of arbitrary icons; for example. in the design of a warning symbol for radio active material.

Question 8

8 Chunking

Answer 8

A technique of combining many units of information into a limited number of units or chunks. so that the information is easier to process and remember. Relate this to 117 plus or minus 2.11

Question 9

9 Closure

Answer 9

A tendency to perceive a set of individual elements as a single. recognizable pattern. rather than multiple. individual elements.

Question 10

10 Color

Answer 10

used in design to attract attention. group elements. indicate meaning. and enhance aesthetics.

Question 11

11 Common Fate

Answer 11

Elements that move in the same direction are perceived to be more related than elements that move in different directions or are stationary.

Question 12

12 Comparison

Answer 12

A method of illustrating relationships and patterns in system behaviors by representing two or more system variables in a controlled way. Relate this to absolute & relative judgment.

Question 13

13 Confirmation

Answer 13

A technique for preventing unintended actions by requiring verification of the actions before they are performed. Relate this to constraint and forgiveness. 88A verification of what you have done is or was achieved; or is about to be achieved.

Question 14

14 Constraint

Answer 14

A method of limiting the actions that can be performed on a system. Note that these constraints can be physical and/or psychological. The psychological constraints are more relevant and interesting in term of human factors. 88 It can be physical or psychological. It prevents you from doing a certain thing. E.g. triangles on the concrete that look like spikes psychological

Question 15

15 Cost Benefit

Answer 15

An activity will be pursued. an action will be taken. and/or a behavior will be elicited only if the benefits are equal to or greater than the costs.

Question 16

16 Depth of Processing

Answer 16

Information that is analyzed deeply is better recalled than information that is analyzed superficially.

Question 17

17 Development Cycle

Answer 17

This is not actually a design principle. This is more of a design process. Relate this to the Stages of Human Factors Design found on one of your handouts.

Question 18

18 Entry Point

Answer 18

A point of physical or attentional entry into a design.

Question 19

19 Errors

Answer 19

An action or omission of action yielding an unintended result. There are two basic types of errors 1 slips unintended actions. and 2 mistakes the action is intended. but it is the incorrect action.

Question 20

20 Factor of Safety

Answer 20

The use of more elements than is thought to be necessary redundant systems or elements to offset the effects of unknown variables and prevent system failure. Relate this to Economy Coding and Security Coding. Relate also to Redundancy Gain.

Question 21

21 Feedback

Answer 21

information originating from the system being used by the operator. Compare this to KR Knowledge of Results . KR is information originating with a person real or virtual . This information can be used by the user to make corrections in his or her actions.

Question 22

22 Fitts Law

Answer 22

The time required to move to a target is a function of the target size and distance to the target. 88 The further away it is the harder it is to acquire. The smaller it is the harder it is to acquire. 88 E.g. small keyboards

Question 23

23 Flexibility Usability Tradeoff

Answer 23

As the flexibility of a system increases. its usability decreases. NOTE this may be a true statement. but it also needs to be clarified. First one must define usability. The way it is described here is similar to ease of use. In other words a usable system is easy to use. A system that is more flexible has more options and can therefore perform more actions. Ease of use in not always the most important consideration. According to the original definition above a Jitterbug phone is more useable than Blackberry; however. in the hands of a well trained user. the Blackberry offers more options and therefore more useable when one needs to accomplish more tasks. 88 You cannot have both.

Question 24

24 Forgiveness

Answer 24

Design elements that reduce the probability of errors and minimize the negative consequences of errors when they do occur.

Question 25

25 Form Follows Function

Answer 25

The form given to a system is consistent with the purpose of the system and each element of that system. From a purist?s perspective an automobile would not have chrome trim. pin stripes. wood grain molding. nor shiny wheels. None of these elements contribute to the actual functioning of the automobile; HOWEVER. we have already learned that aesthetics play an important role in usability; therefore. one must balance a pure form approach with the aesthetics of a system. 88 Form follows function?.not interested in the beauty or design.

Question 26

26 Garbage In ? Garbage Out GIGO

Answer 26

The quality of system output is dependent on the quality of the system input.

Question 27

27 Good Continuation

Answer 27

Elements arranged in a straight line or a smooth curve are perceived as a group. and are interpreted as being more related than elements not on the line or curve.

Question 28

28 Gutenberg Diagram

Answer 28

A diagram that describes the general pattern followed by the eyes when looking at evenly distributed. homogeneous information. NOTE This is an interesting principle. We need to explore this in more detail.

Question 29

29 Hick?s Law

Answer 29

The time it takes to make a decision increases as the number of alternatives increases. 88 It is quicker to do if you break things up.

Question 30

30 Hierarchy

Answer 30

Hierarchical organization is the simplest structure for visualizing and understanding complexity. Categories include a Trees. b Nests. and c Stairs.

Question 31

31 Highlighting

Answer 31

A technique for bringing attention to an area of text or an image. The techniques include a General. b Bold. Italics. & Underlining. c Typeface. d Color. e Inversing. and f Blinking.

Question 32

32 Iconic Representation

Answer 32

The use of pictorial images to improve the recognition and recall of signs and controls. Types of icons include a Similar. b Example. c Symbolic. and d Arbitrary. Relate this to Pictorial Realism. 88 It should be intuitive.

Question 33

33 Immersion

Answer 33

A state of mental focus so intensive that awareness of the real world is lost. generally resulting in a feeling of joy and satisfaction. Note that this principle is a rather emotional in nature almost like being in the zone. Compare this definition of immersion to that of an experience with an ecological interface such as the Wii controller. Also compare it to the immersion perspective in frames of reference used in virtual navigation.

Question 34

34 Layering

Answer 34

The process of organizing information into related groupings in order to manage complexity and reinforce relationships in the information. The two basic kinds of layering include a two dimensional and b three dimensional.

Question 35

35 Legibility

Answer 35

The visual clarity of text. generally based on the size. typeface. contrast. text block. and spacing of the characters used. Relate this to readability and comprehension when using upper case and lower case letters.

Question 36

36 Mapping

Answer 36

The relationship between controls and their movements or effects. Relate this to Proximity Compatibility and Display Compatibility. It would be helpful to refer to the interface head model on an earlier handout.

Question 37

37 Mental model

Answer 37

Cognitive representation of a system. event. object. idea. process. etc. Refer to the Head in the interface model in an earlier handout.

Question 38

38 Ockham?s Razor

Answer 38

Given a choice between functionally equivalent designs. the simplest design should be selected. Compare this to the principle of parsimony.

Question 39

39 Performance Load

Answer 39

The greater the effort to accomplish a task. the less likely the tack will be accomplished successfully.

Question 40

40 Performance vs. Preference

Answer 40

The designs that help people perform optimally are often not the same as the designs that people find most desirable. The example in the text is the Dvorak Keyboard. The history of the QWERTY Keyboard is very interesting. Look it up.

Question 41

41 Picture Superiority Effect

Answer 41

Pictures are remembered better than words.

Question 42

42 Progressive Disclosure

Answer 42

a strategy for managing information complexity in which only necessary or requested information is displayed at any given time.

Question 43

43 Proximity

Answer 43

Elements that are close together in time and/or space are perceived to be more related than those that are farther apart. Kind of like proximity compatibility.

Question 44

44 Recognition Over Recall

Answer 44

Memory for recognizing things is better than memory for recalling things.

Question 45

45 Redundancy

Answer 45

See Redundancy Gain. It is a good thing. You gain either understanding or your ability to respond in redundancy. E.g. new gas tanks lets you know before you run out of gas.

Question 46

46 Serial Position Effects

Answer 46

A phenomenon of memory in which items presented at the beginning and end of a list are more likely to be recalled than items in the middle of a list. Relate this to the primacy effect and the recency effect. Note the importance of these to latter principles in Performance Appraisal and Interviewing.

Question 47

47 Signal to Noise Ratio

Answer 47

The ration of relevant to irrelevant information in a display. Compare this to the Data to Ink ratio.

Question 48

48 Similarity

Answer 48

Elements that are similar are perceived to be more related than elements that are dissimilar.

Question 49

49 Visibility

Answer 49

The usability of a system is improved when its status and methods of use functions are clearly visible.

Question 50

50 Wayfinding

Answer 50

The process of using spatial and environmental information to navigate to a destination. This is a general principle that relates to a spatial orientation and spatial visualization. b landmark. route. and survey knowledge of an environment. Note also that the design of YAH maps is related to wayfinding. Logical reversal or negation. You have to logically reverse. E.g. a turn right sign X ed out. Not the most effective way to convey information.