Case Study:
Xorthwind Stoneware makes consumer stoneware products. Stoneware is fired in a kiln, which is an enclosure made of a porous brick having heating elements designed to raise the internal temperature to over 1200°C. Clay items such as stoneware can be hardened by firing them, following a particular temperature pattern called a firing curve. Quality and cost problems led Xorthwind to examine better ways to control the firingcurve. Alternatives available to them included
1. Direct human control (the temperature sensitivity of the human eye cannot be matched by any automatic control)
2. Use of a KilnSitter, a mechanical switch that shuts off the kiln at a preset temperature
3. Use of a pyrometer, an electrical instrument for measuring heat, with a programmable controller
4. Use of a pyrometer and a computer
The criteria used to determine the best choice included installation cost, effectiveness, reliability, energy savings, maintenance costs, and other applications. A decision matrix evaluation method was used. Under a variety of criteria weights, the use of a pyrometer and a computer was the recommended choice. The exception was when installation cost was given overwhelming weight; in this case the use of a KilnSitter was recommended.
Discussion
Real life is always more complicated than any model used for analysis. In reading about a case in which decisions are made, the complexity of the real decision process is always hidden, because the very process of describing the situation is itself a model. In describing something, choices are made about what is important and worth describing and what is unimportant and not worth describing. In real life, one has to go through a process of separating from a great mass of information exactly what is important and what is not important. The process of solving the quality and cost problems for Xorthwind Stoneware first involved collecting a great deal of information about the manufacturing process. Many people were interviewed, production was observed, and technical details of stoneware chemistry were researched. Market analysis was required to identify possible solutions to the process. Several person-weeks of work were required to gather the information to create the decision matrix mentioned above. We often concentrate on the mechanics of using a decision tool instead of the mechanics of getting good data to use as input to the tool. In many cases, getting good data is 90% of the solution.
Think of an everyday decision situation that you have been involved in recently: it might be deciding which novel to buy, which apartment to rent, or which movie to go to.
Q1. Write down a one-page description of the decision. Include where you were, what choices vou had, what you chose to do, and why.
Q2. Think about how you decided what to write for Question 1. Was it easy to know what to include in your description, and what not to include?
Q3. Can you immediately identify alternatives and criteria, as formally defined, from your one-page description? If not, why not?
Q4. Construct a formal decision matrix model for your problem, augmenting the alternatives and criteria if necessary. Fill in the weights and ratings. Comment on any difficulties vou have coming up with the weights and ratings.
Q5. Calculate the overall score for your decision matrix. Did you actually choose the one with the highest score? If not, why not?
Your answer must be, typed, double-spaced, Times New Roman font (size 12), one-inch margins on all sides, APA format and also include references.