"That's not even a unit of measure!" & other gaffs

[Uncwilly]

So, occasionally one runs into an error that is so funny, pitiful, heinous, etc. that it defies commonsense. When the error comes from a person that should know better, the party responsible works in that field, it is espcially bad. Please share some of the worst offenses that you have seen. And try not to get too technically deep.

Here is one that I observed and tried to get corrected (more than once):
a figure was being reported in "cubic years". To the very best of my knowledge that isn't a unit of measure and can't be. I have a hard time to see how to make even a derived unit that is y³ with no other unit associated. The individual who made the blunder was an engineering type working on an earth-moving project.

[Dougal]

two days ago i put up a post saying that 123 was a prime number,somehow i managed to calculate (1+2+3)/3=2 wrong.

[cheesehead]

Originally Posted by Uncwilly

So, occasionally one runs into an error that is so funny, pitiful, heinous, etc. that it defies commonsense. When the error comes from a person that should know better, the party responsible works in that field, it is espcially bad.

But the "cubic years" error you mention looks almost certain to be a typo or misspeak for "cubic yards", rather than some misunderstanding or ignorance about units!

Here is one that I observed and tried to get corrected (more than once):
a figure was being reported in "cubic years". To the very best of my knowledge that isn't a unit of measure and can't be.

... and the brief quotes on the Google result page for your link show right away that almost all occurrences are in a context where "cubic yards" is a commonly-used unit -- sometimes in the very same sentence.

It's a simple typo, not some kind of reprehensible ignorance.

The individual who made the blunder was an engineering type working on an earth-moving project.

... in which "cubic yards" is, undoubtedly, a commonly-used unit.

- - -

I'd bet money that you'd find that the frequency of occurrence of "cubic years" is much lower among individuals working where the metric system is used exclusively than among individuals working where "cubic yard" is a commonly-used unit from the the U.S. customary system -- and it's not because year is an SI unit (it isn't).

[frmky]

Originally Posted by Uncwilly

To the very best of my knowledge that isn't a unit of measure and can't be.

Sure it can. Using standard relativistic units c = 1, so a cubic year corresponds to the volume of a cube of length one light year on each side. Although I doubt anyone will be moving that much earth.

Although if you truly want to use relativistic units you should be measuring distances in units of the Compton wavelength, but that's ridiculously small so no one does.

[Uncwilly]

Originally Posted by cheesehead

But the "cubic years" error you mention looks almost certain to be a typo or misspeak for "cubic yards", rather than some misunderstanding or ignorance about units!

How ever the individual in question was repeatedly advised of their error and failed to correct it each and every time (the usage of c.y. or yd³ is so much better and more common in the context.) There were many other errors in the document, the individual was advised of them and failed to correct them. (This was a document that they were supplying to their boss on an on-going basis.) They circulated the document asking for comments and received much clarification, but failed to incorperate any suggestions. One time they circulated it asking for comments, so I opened up Word, turned on 'track changes' and went to town. That was the end of that document being circulated.

[Uncwilly]

Originally Posted by frmky

Sure it can. Using standard relativistic units c = 1, so a cubic year corresponds to the volume of a cube of length one light year on each side. Although I doubt anyone will be moving that much earth.

That would be a cubic light-year. Please provide an actual example of that usage.

[frmky]

Originally Posted by Uncwilly

Please provide an actual example of that usage.

I certainly don't need to as it is correct per the usual rules of relativistic units. But for your entertainment:

http://created.web229.net/milky-way/gb/sevol.htm
http://www.archive.org/stream/outlin...48mbp_djvu.txt

BTW, there's nothing fundamentally wrong with cubic time. Something as basic as power is expressed as a mass-area per cubic time.

[Uncwilly]

Originally Posted by frmky

I certainly don't need to as it is correct per the usual rules of relativistic units. But for your entertainment:

http://created.web229.net/milky-way/gb/sevol.htm
http://www.archive.org/stream/outlin...48mbp_djvu.txt

I looked at both, and there was no mention about relativity that I could find near to volume measurements.

Your first link consistently used "years of light" even in the volume form "cubic years of light". This does not help your cause.

The second link used the term exactly once, but used "cubic light years" closer to 12 times and from my search of the document (top to bottom), always used "light years" for distance never "years".

I can see y/y as a unit (but that is not years squared). But your example of "mass-area per cubic time", but that is a complex unit of say kgm²/y³. That is not a simple y³

[frmky]

[retina]

Time/distance what does it matter, all the same to me. Three time dimensions and one distance dimension, what is the problem with that?

BTW: I'll meet you on the corner of Tuesday-6^th and Friday-17^th, on the Sunday-4^th floor, at say around 14.6 metres. I'm buying.

[cheesehead]

Originally Posted by Uncwilly

How ever the individual in question was repeatedly advised of their error and failed to correct it each and every time (the usage of c.y. or yd³ is so much better and more common in the context.) There were many other errors in the document, the individual was advised of them and failed to correct them. (This was a document that they were supplying to their boss on an on-going basis.) They circulated the document asking for comments and received much clarification, but failed to incorperate any suggestions.

Apparently, correcting typos that were not likely to mislead the intended readership was a low priority.