Performance-Oriented Logistics Assessment (POLA)

This report is a user's manual for the Logistics Decision Model (LDM), which was developed by the Performance-Oriented Logistics Assessment (POLA) project to help build the logistics portion of the Army five-year program. POLA estimates the effects on combat performance of alternative investments in logistics resources. LDM simulates the ways that Red and Blue combat forces are influenced by combat service support capacities (e.g., transportation, ammunition handling, maintenance) and logistics resources (e.g., stocks of ammunition, war reserve equipment, replacement personnel). By itself, LDM cannot do all that is required of the POLA methodology. It can estimate the effect on combat performance of varying the capacities to perform certain logistics functions, such as ammunition handling, but those capacities must be estimated from physical resources. LDM reads data from four different types of input files: the ATTRITION file contains data that relate the outcomes of combat to the numbers and kinds of weapons engaged; the SUPPORT files describe the structure and activities that support the combat forces; the TIME PHASE file specifies the amount of each resource that enters the simulation; and the OUT SPEC files specify what variables appear in the output files. LDM contains two modules that perform computations: the support module computes the rates of all activities performed by the theater support structure to make weapons available for combat, and the combat module computes the outcomes of combat between the available Blue and Red weapons. Activities (and many combat outcomes) are defined by their effects on resources, such as consumption, production, or transport.