Uncertainty, Variability, & the Challenge for Engineering
People generally do not like uncertainty, often attempting to view the world in a deterministic fashion, with clear causes & predictable effects. It's a natural tendency, but such a view fails in the real world of engineering design & system management. The future is rarely certain, so engineers think about outcomes in terms of probability.
Engineers strive for reliability & optimal results, & do so by considering both variability & uncertainty - two key concepts in the field of probability analysis.
Variability is crucial in determining how to achieve reasonable reliability against collapse or structural failure, for example. What does variability look like? Think temperature changes from day to day & place to place; strength differentiation in concrete beams; & how identical system components, both mechanical & electrical, will operate for different numbers of hours before failing. These are variables.
Uncertainty is typically used to describe our limited knowledge of the parameters that allow for variability. Think of uncertainty as another kind of randomness.
One thing is certain: This virtual discussion will be enriching & enlightening. Jery Stedinger, Cornell's Dwight C. Baum Professor of Engineering Emeritus, is an engaging conversationalist & a true expert in the field of engineering.