The components of DSS Mathematical problems page 151

All models are made up of four basic components. Mathematical relationships links these components together.

Result (outcome) variables

• Reflect the level of effectiveness of a system, ho well the system attains its goals. These variables are outputs.
• Considered dependant

Decision variable (pg 58, 152)

• Describes alternative courses of action. The decision mkaer controls the decision variables.

uncontrollable variables (or parameters)

• Factors that affect result varibales but are not under the control of the decision maker.
• Some of these variables limit the decion maker and therefore form what are called constraints of the problem.

intermediate result variables

• Reflect intermediate outcomes in mathematical models. eg. determining machine maintenance scheduling, spoilage, total profit, employee satisfaction

Mathematical models

Use mathematical techniques to link decision variables, uncontrollable variables, parameters, and result variables together:

• Decision Variables have values that describe choices.

• Uncontrollable Variables have values that are outside the decision-maker’s control.

• Parameters are fixed factors (constants).

• Intermediate Result Variables are intermediate outcomes.

• Result Variables are outcomes dependent on chosen decision variables, uncontrollable variables, parameters and intermediate results.

Quantitative models

• Quantitative relationships.
• Variables involved in the model have numerical values.
• Outcomes are numerical.

“if the sales this year are $400,000 and they increase by 10% next year, the sales will be $440,000”

Nonquantitative models (qualitative models)

• Qualitative relationships.
• Variables involved in the model have qualitative values that are represented within the model by numerical values.
• Outcomes are qualitative / numerical.

“indicate your happiness with our product on a scale of 1 (very unhappy) to 5 (very happy). …”

Results (outcomes) = f(decision variables, uncontrollable variables, parameters, intermediate results)