Dust Yourself Off

Phylagen, a San Francisco biotech company, has developed a technique for tracking previous locations of objects based on the composition of dust the object has collected.

In another experiment, the sampling technology allowed researchers to determine where a person had walked within 1 kilometer in San Francisco, because of the microbes picked up by their shoes.

Right now, this technique is proposed for use in tracking manufacturing locations in supply chains.  If it’s successful, expect it to be used first in forensics, and then in ubiquitous “backwards” location tracking for behavior profiling.

Oh, great.  Now, in addition to fresh clothes and a good scrub in the shower, I need to swap/brush/scrub my shoes to keep the snoops of the world at bay.


Need a 3-Way?

One of my techno-nerdy students got me hip to the Logitech Anywhere2 wireless mouse.  It can be linked with a dedicated USB device AND paired with Bluetooth-capable devices.

It’s button #7 – switch devices!

So now my old Windows desktop computer, my Surface laptop, AND my old Surface tablet can be clicked with a single mouse.

Just like my desk, only less cluttered

How cool (and handy) is that?

The Fourier Transform, explained beautifully

At the Better Explained blog, Kalid Azad hits another home run with An Interactive Guide to the Fourier Transform.

Here’s a plain-English metaphor:

  • What does the Fourier Transform do? Given a smoothie, it finds the recipe.
  • How? Run the smoothie through filters to extract each ingredient.
  • Why? Recipes are easier to analyze, compare, and modify than the smoothie itself.
  • How do we get the smoothie back? Blend the ingredients.

Here’s the “math English” version of the above:

  • The Fourier Transform takes a time-based pattern, measures every possible cycle, and returns the overall “cycle recipe” (the amplitude, offset, & rotation speed for every cycle that was found).


Tip from Kotke, who has a cool Fourier Transform video.

Stanford Invents AI Gaydar, Flubs Write-Up

Yilun Wang and Michal Kosinsksi, researchers at Stanford’s Graduate School of Business, have developed a neural-net classifier that purportedly detects sexual orientation (in caucasians).
The authors report an avalanche of experimental results, and claim the classifier can “correctly distinguish between gay and straight men 81% of the time, and 74% for women.”  OK, that’s the sensitivity of the gadget.  What about specificity, i.e. how well does it correctly distinguish folks who are not-so-gay?  Without that second number (as well as an estimate of prevalance), it’s not possible to estimate the false positive and false negative rates for this thing.  Very important, if some of the more Orwellian applications mentioned by the authors come to pass.
I give the authors a “C,” for incomplete work.
Update: Dan Simmons, writing at the Andrew Gelman blog, writes a rambling, fascinating takedown of this “research,” from both the scientific and MSM points of view.  Based on just the statistical problems, I’m changing the grade to a “D-.”

The Examined Life is Worth Living

Scurrilous Commentator Fred Reed demonstrates how a grown-up examines his prejudices on the way to wisdom

Most Latinos of the south are either a mixture of Spanish and Indian, or sometimes pure Indian….Are they, as nativists insist, of very low IQ–83–and have they enstupidated the Spanish? Horrendously primitive?

Without thinking about it, I had the entrenched idea that they were just that. I wasn’t conscious that it was either an idea or entrenched–just a fact. It didn’t occur to me that I knew virtually nothing about these  people, or that there was anything to know.

What pulled me up short was their architecture.

and gives us a cultural history lesson along the way.


Included is this wonderful link to the Mayan numbering system, which makes ours look a bit rickety.


Blinded Me with “Science”

Writing in The New Atlantis, Daniel Sarewitz says “Science, pride of modernity, our one source of objective knowledge, is in deep trouble.”  The public has swallowed the myth of scientism and Vannevar Bush’s self-serving rationalization for federally-funded Big Science:

Scientific progress on a broad front results from the free play of free intellects, working on subjects of their own choice, in the manner dictated by their curiosity for exploration of the unknown.

Sarewitz quotes Richard Horton, editor-in-chief of The Lancet, who puts it like this:

The case against science is straightforward: much of the scientific literature, perhaps half, may simply be untrue. Afflicted by studies with small sample sizes, tiny effects, invalid exploratory analyses, and flagrant conflicts of interest, together with an obsession for pursuing fashionable trends of dubious importance, science has taken a turn towards darkness.

There’s much, much more, including Alvin Weinberg’s decades-old identification of the problem of trans-science. Read the whole thing.

Tip from Gary Jones, who was apparently so flabbergasted at the completeness of this article that he (uncharacteristically) didn’t even comment.