Tuesday, August 28, 2007

Retrospectively Protesting My Undergraduate Education

Uncertainty analysis. Do an uncertainty analysis. Right. This is the type of thing printed in my lab notes (we didn't have a lab text in most classes). Honestly, after reading the 1997 ISO Guide to the Expression of Uncertainty in Measurement (GUM) for a second time, I am quite convinced that it is not possible to do a satisfactory analysis with the information given to us in those labs. The uncertainties of all the instruments need to be known; the physics of the experiment practically needs to be known in order to figure out what could be contributing uncertainty to the measurements; alternatively, a lot of sample data must be taken to create type A uncertainties. Unless an entire experiment is designed with uncertainty analysis in mind, and the students are made acutely aware of everything that needs to be done to obtain this information, there is no hope for an uncertainty analysis.

BTW, why wasn't the GUM a required text in at least one of my classes? The information therein is critical to modeling uncertainty, especially with regard to limiting what may be said about the uncertainty of a particular measurand and the propagation of uncertainty.

A reading of my old thermodynamics text (published in 1998) prompted this complaint. I was looking for steam table data with uncertainty information. Of course, it is not there. Interestingly, my text doesn't even reference data from the then-latest International Association for the Properties of Water and Steam Industrial Formulation 1997 (IAPWS-IF97) steam tables. There is also a non-industrial formulation from 1995 that has a simpler formulation but takes longer for a computer to calculate. Both formulations have uncertainty data. Instead, my book's tables were "adapted from" another thermodynamics textbook published in 1986.

Oh noes!!!11!1! Heaven forbid we use a relevant international standard. Ridiculous.

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