This is a place where you can ask, and possibly obtain answers, on how to measure something. See the Rules to understand how it works.
If you are someone experienced in measuring things and see a question here, you are welcome to respond. Again, see the Rules to understand how that works.
This blog also has links to specific websites that provide many in-depth resources relating to measurements of all types, especially the difficult ones in Industry & Science. Check those out, too, if you are seeking a specific solution to a problem.
Bet you never knew measuring could be so busy!
While on the train to NYC this morning, two recent events coalesced into the above question.
First was the news story seen on yesterday’s AdAge website and one we talked about on MeasurementMedia.com – “web media measurement doesn’t work!”. It echoed our small experiences over the past five years or so that the traffic reported visiting our websites according to Google and our own server-based counting methods differed by more than an order of magnitude – or more!
Then, secondly, there was the interesting experience that I had while visiting the SMX conference & Expo just a week ago at the Javits Center in NYC. I had listened to a panel chat on the future of Google by noted experts – none from the Big G. Several were selling copies of their “Google books”. So, I got in line to buy one and get it signed by an author. Continue reading
Wow! That’s a question much like:”How long is a piece of string?”
The quick answer is, “It all depends!”
The detailed answer lies in the results of what is being measured, by what measurement device(s), under what conditions and the skills or experience of the person using the device(s).
One phenomenological way to determine the error is to make a series of them (observations) and determine the “scatter” or variability in the results. If you have no variations, then the measurement device(s) are most likely not sensitive enough. That assumes, of course, that the measurement is not a foolish, tautological or trivial one like: “How many items constitute a pair?”
It is safe to say that all really quantitative measurements have errors and the errors are composed of at least three components: (1) Random, (2) Fixed and (3) Situational.
The “fun” in measuring things, is to determine the most likely errors and then verify that they are as expected.
This is a practical answer for those who are unsure about the size of their foot and consequently their show size. It is aimed at ladies shoes
Visit: http://ladieshoes.wordpress.com/2010/09/19/how-to-measure-your-foot-or-rate/ to find out!
Found this rather heavy, scientific blog post at: http://memming.wordpress.com/2010/07/18/an-engineering-introduction-to-measure-theory/. The paragraph below includes a link to the Wikipedia article on “Measure Theory”. If you are “into” that sort of thing, here’s a quotes from the opening paragraph:
A measure is a convenient mathematical object (function) that can represent the positions of strawberries in a field, distribution of water in the ocean, or probabilities of winning over the lottery numbers — the measure counts the number of strawberries in a given area, reports the amount of water in a certain sea, and evaluates the probability of a lottery ticket to win. This abstract unifying framework enables one to rigorously ‘measure’ quantities over a space, and also enable integration. It also allows elegant notation for probability theory. Here we briefly describe key ideas of measure theory without proof.
How do we?
(This is what I call a “seed question” – we actually know the answer, but wonder if every reader of this blog does, too. Probably not)
Have you ever thought about it?
Anyone out there in “Webland” know?
(I really don’t expect an answer anytime soon, but it can hang in the breeze for a few days before we answer it.)