Propagation of Uncertainty An Uncertainty Budget Example

Abstract

Finding the uncertainty of a single measurement is just part of the story. In this chapter we show how to combine the uncertainties from several measurements to determine the total uncertainty for a calculated quantity. For example, while generating a cost estimate for repaving a rectangular parking lot, you may need to combine the uncertainties in measured distances (length and width of the lot) to find the uncertainty in area. The chapter develops two extensive examples: determination of the elastic modulus from an experiment measuring several different quantities, and a radiation heat transfer problem. In both examples uncertainty budgets are developed and demonstrate how they can be used, for example, to minimize the cost of equipment.