CS 66.460
Introduction to Graphical Human-Machine Interfaces
Spring 1997
IN-CLASS EXERCISE #1
Conceptual User Models and Metaphor

The Goal: To gain experience constructing a conceptual user model of a system.

The Problem: When we are confronted with a software system or a device we often form a mental model of how the system operates. Such models, since they are formed by the user of the system, are called user models.

Often, designers pick a metaphor to help explain the system to the user. However, when an inappropriate metaphor is chosen, the user may devise an inconsistent model.

What To Do:

Divide up into groups of 3-4 people. You are to analyze the typical scenario below and come up with a user model for the voice mail system.

The Scenario

You have arrived at your friend's office for lunch. You told your friend that you would call from the lobby phone when you got there. You pick up the phone and dial your friend's extension:

Ring. Ring. Click.

Oh no you think not another voice mail system. First you hear a general message from the voice mail system telling you:

``The person you are trying to reach is not available, you may press 0 for the switchboard operator or stay on the line and leave a message in that person's voice mailbox.''

Then you hear your friend's voice:

``I'm not here now. But if you'll leave a message after the tone I will get back to you as soon as I can.''

You leave a message and hang up.

The Deliverables: Each group is to turn in

1. a cover-sheet listing all of the participants in your group
2. a sketch of the user model of the voice mail system
3. a short paragraph or two describing how you came up with the model
4. also, if you used any metaphor to help you model the system please indicate the metaphor used.

In the next class each team will transfer the sketch of their model to an overhead transparency and briefly present their model to the class.