Standard Deviation

September 1st, 2011
math
Standard deviation is the average distance between each data point and the mean of the data. It's defined as:

Why isn't it:

That is, why is it the square root of the average of (x-mu)^2 instead of just the average of |x-mu|? How is the squared version more useful?

Update 2011-09-01 I had left out the square root on the standard deviation.

Comment via: google plus, facebook

Recent posts on blogs I like:

Development RCTs Are Good Actually

In defense of trying things out

via Thing of Things March 25, 2024

Clarendon Postmortem

I posted a postmortem of a community I worked to help build, Clarendon, in Cambridge MA, over at Supernuclear.

via Home March 19, 2024

How web bloat impacts users with slow devices

In 2017, we looked at how web bloat affects users with slow connections. Even in the U.S., many users didn't have broadband speeds, making much of the web difficult to use. It's still the case that many users don't have broadband speeds, both …

via Posts on March 16, 2024

more     (via openring)