Re: [Phys-L] Uncertainty Calculator

["Donald Polvani" <dgpolvani@verizon.net>]

On Saturday, January 21, 2017 5:09 PM, John Denker wrote:

> I cobbled up an Uncertainty Calculator.  Given some input variables with error
> bars, it calculates the output variable and its error bars.
>
>    https://www.av8n.com/physics/uncertainty-calculator.html

This looks useful.  I haven't had time to try it out in any detail.  What I have found out immediately is that, on my Windows 10 machine, the calculator will not run using Internet Explorer 11, but will run using Edge.

> There are other online Uncertainty Calculators out there.  However, the others all seem to rely on «propagation of error bars», which is more laborious, less powerful, and less reliable. I will never in a million years understand why anybody would bother with that.

It may be "inertia" - the reluctance to change to better techniques now allowed by improved technology.  I am now retired, but when I learned about error propagation, personal computers were non-existent.  Hand-held calculators were non-existent.  We used slide rules.  Propagation of error bars was an approach that allowed someone with a slide rule to produce an approximate answer.  I don't recall anyone telling me about the "crank three times method" (perhaps, because that is a John Denker innovation?) but that would have appealed to me.  Once I found out about the Monte Carlo method, and had a personal computer available, that became my method of choice.

Don
Dr. Donald G. Polvani
Adjunct Faculty, Physics, Retired
Anne Arundel Community College
Arnold, MD 21012