Spiderplots versus Tornado Diagrams for Sensitivity Analysis

Abstract

Sensitivity analysis, supported by computer hardware and software, can easily overwhelm an analyst or decision maker with data. However, this data can be organized in a readily understandable way using well-designed graphs. Two graphical techniques, spiderplots and tornado diagrams, are commonly used respectively by engineering economists and decision analysts. Their advantages are complementary. Management scientists should often use both to convey their results to decision makers succinctly and clearly. The simpler tornado diagram can summarize the total impact of many independent variables. An individual spiderplot displays more information about a smaller number of variables. This includes the limits for each independent variable, the impact of each on the dependent outcome, and the amount of change required to reach a break-even point.