The Art of Approximation

摘要

Once upon a time, many college students in science and engineering took pride in their ability to make mental estimates to check the result of a computation or experiment-estimates that were correct to within an order of magnitude. Such estimates helped determine whether a lab result made sense and were especially useful for checking the result of an actual computation. Because students typically carried out such computations using a slide rule or perhaps a desk calculator, manual errors were always a possibility. I can't recall much class time being spent on teaching this rapid approximation skill. Perhaps we learned it in the usual way-by imitating our professors.