
How To Analyze Data Using the Average - brett
http://betterexplained.com/articles/how-to-analyze-data-using-the-average/
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graywh
Poor title, but great descriptions and examples.

Bonus for harmonic mean.

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kalid
Cool, glad you liked the article. Yeah, I'm still working on the zen of making
catchy "click me now!" titles :).

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yters
I like the aim of your blog. I've noticed that in all subjects there are a few
key ideas that everything revolves around, plus a few key results from these
ideas. For some reason, the subjects are not organized around those points.

School would be so much easier and interesting if the subjects were organized
better.

I think the bad organization is a consequence of school performance being
measured by tests. It is much easier and quicker to merely memorize the
formula and regurgitate than to really understand what is going on. Then the
people who learned by parroting become teachers and are even less able to
explain the crucial principles; resulting in a vicious cycle.

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kalid
Thanks, glad you like the site. I completely agree -- many ideas can be boiled
down to a few key concepts, yet most of the time we're taught to plug and chug
(and inevitably forget).

It surprsies me how often "cram and forget" is the operating mode for
education (I had my share of that). Yep, I think measuring performace with
tests is a big part of it.

You hit the nail on the head about student interest as well. Many people end
up hating math because it is often taught in that rote, formulaic manner.

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ejs
Interesting discussion, but I think the average is more usefully thought of as
the best unbiased predictor. In other words, given no other information about
the process the mean is the best prediction one can make.

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kalid
Yeah, there's lots of different interpretations for the average. The
predictive one works well (expected value), another one is where the
"balancing point" would be if you had physical weights at those coordinates.

If you had 1kg weights at distances 2 3 and 10 (sum of 15), you should put the
fulcrum of a lever at 5 to keep the set balanced. (Torque on right: 10 - 5 =
5. Torque on left: 5 - 2 = 3, and 5 - 3 = 2, for a total of 5).

Different sized masses? You literally take the weighted average :).

