Monday, December 4, 2017

'Nowhere To Sleep': Los Angeles Sees Increase In Young Homeless

Anna Scott, reporting for NPR, described changes to the homeless census in LA. It applies to stats/RM because an improvement in survey methodology lead to a big change in the city's estimation of number of homeless young adults.

I also think this is also a good piece for teaching because the story keeps coming back to Japheth Greg Dyer, a homeless college student who aged out of the foster care and was sort of tossed into the world on his own.

Straight from NPR:

Homelessness hasn't necessarily increased dramatically. Instead, these findings seem to indicate that they finally have a reliable way to count young adult homelessness due to a better understanding of young adults. The dramatic increase is methodological.

Monday, November 27, 2017

Roeder's What If God Were A Giant Game Of Plinko?

Roeder, writing for, has come up with a new way to illustrate the Central Limit Theorem.

And it uses Plinko, the beloved The Price is Right game!

Well, a variation upon Plinko, featured on the NBC game show The Wall. Their Plinko is much larger and more dramatic and the slots at the bottom go up to $1 million. See below.

How does CLT come into play? Well, the ball is randomly thrown down The Wall. And people jump around and hope for certain outcomes. But what outcome is most likely over time? For the pattern of ending positions to conform to the normal curve. Which it did. See below.

The article itself gets pretty spiritual as the author starts talking about randomness, of the show and of life. You can steal, but cite, the game show as example of CLT as he has provided a clip of the show as well as a graph of positions of the orbs, both of which help illustrate the theorem.

Monday, November 20, 2017

Math With Bad Drawing's "Why Not to Trust Statistics"

Bad Math with Drawings has graced us with statistical funnies before (scroll down for the causality coefficient). Here is another one, a quick guide pointing out how easy it is to lie with descriptive statistics. Here are two of the examples, there are plenty more at Math With Bad Drawings.

Variance example