AAOM Handbook

MP.10 Establish data boundaries Context

When constructing measures we also need to consider the boundary conditions, i.e. what is included in the measure and what is to be excluded. Two types of boundary conditions need to be considered, the physical boundaries of the process and the data boundaries for the measure. Since the measures of a process are intended to indicate the delivery of the Purpose or the Theory, the conditions in which these are delivered should guide the specification of the data boundary conditions for the measure. Data boundaries are applicable when measuring time. For example, if we are measuring the utilisation of a process, the time boundaries should be set to enclose the period when the process is performing its Purpose, and to exclude the period when the process is not performing its Purpose. The boundary conditions for the theory and purpose measures should be matched. When processes interconnect, as they always do, people often get confused trying to decide whether a particular measure is of a lagging or leading nature. This is understandable because the nature of a measure is relative. The output parameters for one process are typically elements of the theory measures (input in this case) for the following process. For example if you are looking at the grind quality from a mill, it is a lagging measure of the mill operating performance. For a leach circuit, the grind quality will be a leading measure of the process performance. Purpose To determine the data to be included and excluded from the measure Quantity One statement that defines data boundaries of the measurement Quality The data boundaries shall be based on the boundaries to the process delivering its purpose - see examples in Appendix 1 below. Resources This task is completed by the manager responsible for the process. Time The task should be completed prior to measures being developed