An Option Value Chart displays the value of each "option" in your decision model. In DPL, the option value is defined to be the difference in the objective function between when the model is run with a decision uncontrolled so that the optimal alternative is selected, and when the model is run with the decision controlled to a fixed alternative. The fixed alternative can be the Default alternative as specified on the General tab of the Node Definition dialog, or some other alternative as specified in the Option Value Chart Setup dialog.
DPL calculates the option values in the chart by first running the model with all decisions controlled to their Default (or other specified) state. DPL then uncontrols the decision that is first in the tree (i.e., nearest the head of the tree) and runs the model again. The option value for the decision just uncontrolled is the difference in the objective function value between the two runs. DPL then uncontrols the next decision (i.e., the one next nearest the head of the tree) and runs the model again. The option value for this second uncontrolled decision is the difference between the latest model run and the previous run.
Because of the way DPL calculates option values, the chart may look significantly different depending on which Default Alternatives you specified in the setup dialog.
The incremental height (i.e., from the bottom of the bar to the top of the bar) of each bar in the chart represents the option value for each decision.The total height of the last bar (i.e., from the x-axis to the top of the bar) equals the objective function of the model when it is run with no decisions controlled (i.e., with all decisions at their optimal alternatives). Therefore, the total height will be the same regardless of how you specify the Default Alternatives, although the individual bar heights may vary.
Formatting Option Value Charts
You can sort the bars, hide bars and otherwise control the look of an Option Value Chart by using the Chart | Format and Chart | Series tabs of the ribbon.
Versions: DPL Professional, DPL Enterprise, DPL PortfolioSee Also