IN THIS CHAPTER
Persistent storage (cookies)
Scripted image maps
I wanted to implement a classic application often called a decision support system. My experience with the math involved here goes back to the first days of Microsoft Excel. Rather than design a program that had limited appeal (covering only one possible decision tree), I set out to make a completely user-customizable decision helper. All the user has to do is enter values into fields on a series of screens; the program performs the calculations to let the user know how the various choices rank against each other.
Although I won't be delving too deeply into the math inside this application, you will find it helpful to understand how a user approaches this program and what the results look like. The basic scenario is a user who is trying to evaluate how well a selection of choices measure up to his or her expectations of performance. User input includes:
The name of the decision
The names of up to five alternatives (people, products, ideas, and so on)
The factors or features of concern ...