A: Describe a problem common to all input devices
B: Discuss the pros and cons of developing an innovative interface that
breaks all conventions.
C: Discuss the pros and cons of using 1) icons 2) menus in an interface
design.
Evaluate the interface on back using the given
frameworks.
Example answer: "One problem is the transformation of knowledge from the device to data that the system can understand. We introduce "signal noise" and translation errors in this attempt. Also we need to make sure that we try to represent continuous information in a way that appears continuous."
Another acceptable answer would be pointing out that input devices are closely coupled to a specific psychological and physiological set of people.
Some other answers which are not problems of all input devices:
Example answer:
CONS: "It is easier to assimilate than to accommodate, so any innovative interface breaking conventions rules out assimilation as a possibility. The user will not be able to map previous experience to the new interface. Therefore both users and experts will probably be equally lost since experts aren’t able to draw on prior knowledge to apply to new situations. The user’s scripts or schemas will not run if it is completely new but smart users might be able to run their scripts and create a model of what they expect the system to do. The problem is that these scripts may not be applicable in any way and so the user will develop an inaccurate model."
PROS: "If we use a new metaphor, eventually the user will understand it (after originally using it to "scaffold" the learning of the new system) and use it in future applications. The new mental model that the user has may be either structural or functional depending on the design of the system and the inquisitiveness of the user. These understandings, especially functional, may be applied to future understanding. Hopefully this new design "affords" whatever use it is designed for so the user will know how to use the system and for what purpose."
Notes:
In answering this sort of question on an exam, you should respond in the terms and principles taught in this class, rather than in layman’s terms.
A lot of people misused assimilation and accommodation within this question. These are terms describing different ways of learning and were initially introduced by Piaget.
Assimilation refers to the process of learning something which is very similar to something you already know. As an example, if you can work a joystick, then you can easily learn how to use a trackball: this is assimilation. Accommodation refers to the situation in which all of your existing mental models and knowledge don’t map onto the new situation. Accommodation requires breaking down existing mental models and creating new ones in order to understand the new situation or knowledge. An example is moving from the world of DOS to the Macintosh interface: drive letters are used in DOS, but not on the Mac, so to save your files on a floppy on the Mac requires learning the conventions of the Mac.
Another source of confusion was with conceptual and mental models (which are synonymous). Mental models are actively constructed by the user and they exist in your head – they cannot be presented in an interface. An interface can tap into existing mental models, but it cannot create or present them.
Scripts and schemas are closely related to mental models – mental models employ scripts and schemas to represent series of actions to accomplish a task.
Example answer:
"Icons are good to use when the iconic representation maps well to an existing understanding. A good icon will communicate action being done. However icons with no mapping to anything do not aid in helping the user understand what action to perform. Icons work best when they are consistent with an extended metaphor such as the desktop."
"Menus are useful because recognition is easier than recall. Menus allow users to scan options visually rather than recalling command line structures. Menus work best when they are organized in alphabetical, conventional or frequency of use categories to promote efficiency and ease in searching. Menus are not good when too many options are given or when function descriptions are ambiguous or unclear."
Notes:
Again, the best answers (for an exam) are those which use terms and principles covered in class, rather than in layman’s terms.
Based on the evaluation, develop suggestions for redesign of interface.
Example answers:
Focus of attention
In answering this question, you could talk about how we scan from top-down, left-to-right in western culture and how this interface affords us noticing the "Control Panel" title and the left-most icons first. You could also discuss how this works against understanding the interface: the groupings on the right break with this convention because of the way they are arranged and spaced.
Finally, there are a lot of distractions in this interface, such as blinking items, darkly shaded boxes, and an arbitrary use of space, which means there is no real focus of attention.
Organization
In discussing organization, some of the points that can be made are that main function groups are organized on the left, which aids in navigation of the control panel. On the other hand, it is obvious that the items displayed within the "General" category have little in common with each other. From a functional perspective, then, the controls displayed in the right are poorly organized.
Structure of Space
In this dialog box, every bit of space is used, but it results in a cluttered interface which is too busy. Furthermore, the divisions made between the controls suit their individual sizes, but create arbitrary divisions within the space of the dialog box.
Redesign
Some of the best suggestions for redesign included pulling out such items as date and time and creating a separate control panel item for them. That is, group like items with like items.
Others made the suggestion to create a tabbed pane for the individual groups.