## Google Public Data

Last week, Google unveiled their new Public Data Explorer. If you’ve ever seen Gapminder, this is very similar.

In fact, Google bought the Trendalyzer software from Gapminder and applied it to data from Eurostat, the US Census Bureau and many other sources: Datasets

For me, the main question with Google is where they’ll next head in their persistent quest for market share and eventually world domination. Chrome, Android, Google Maps, YouTube, all added to their repertoire and threatened the competitors in those fields. When was the last time you used Mapquest?

With Public Data, the main target seems to be Wolfram Alpha with its database of everything from the lethal dosage of caffeine to algorithms for solving differential equations. Granted, Google is mostly sticking to Gapminder’s domain: global population statistics. But with their tendency to obsessively add new functionality (also last week: bike routes on Google Maps!), it’s only a matter of time.

## Bizarre Fact About Factors

For *any* integers B and x greater than 1, where B is not a multiple of any factors of x: There exists a positive integer n such that (B^n)-1 is divisible by x.

In other words: 999….9999 is a multiple of any given number, except for evens and multiples of 5 (base 10). You just need the right number of nines.

In binary, 1111…111 has the same property.

I won’t write out a formal proof, but here’s a simple explanation:

The decimal expansion of 1/x is a repeating decimal.

Therefore, it’s a fraction over B^n-1.

Inverting both sides of the equation, B^n-1 is a multiple of x.

This doesn’t actually work if x is a multiple of 2 or 5 (in decimal), or in general any of the factors of the radix, because the repeating decimal will have a number of zeroes before it. But it works in all other cases.

Example:

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999999999999999999

99999999999999999999999999999999999999999999999999 is a multiple of 1,337. That’s 570 nines.

Hey, I never said n had to be small.

EDIT: After poking around Wikipedia and playing with Wolfram|Alpha a bit, it seems that an upper bound on N is x-1. A better upper bound, however, is LCM(a,b,c…) where a,b,c are the prime factors of x, minus one.

1337 = 7*191.

LCM(6,190) is — guess what? — 570.

## Jolk Etymology

The computer mouse is not, as many people assume, named after the similar-looking rodent.

In fact, the term derives from the original model number Douglas Engelbart used: J-97.

Engelbart and his team at ARC used a simple code to label prototypes: “n” for nonworking (a wooden model, for example) and “w” for working (a fully-functional test version). The first mouse that really succeeded was the third working model; he planned to announce this via a memo titled “J97w3 device ready for patent.”

History was made when he accidentally typed the first word with his fingers a row too far down on the keyboard: “Mouse device ready for patent.”

## Nerdy Comic!

I’m shameless, but at least I can use LaTeX. (My renderer of choice is the Wikipedia sandbox.)

*EDIT: WordPress isn’t any better with fractions:*

## ‘Tis the season (for Google Live Updates)

‘Tis also the season for Christmas carols on the radio (already? Really, guys?) and animated snow on WordPress’s login page. (I swear to God I’ll switch over to Blogger if they pull that next year.)

Google recently unveiled their Updates feature, which is pretty if not spectacularly useful.

An impressive demonstration is the results for Christmas. I think this, better than any Internet-stats page I’ve ever seen, shows the sheer size of the Web, and specifically Twitter. People are tweeting about Christmas as fast as I can read it, and there’s still more than a week to go. (So seriously, cut it out with the carols.)

78 exabytes is a big number (thanks, Discover!), but it doesn’t drive home the personal aspect as well as the buzz of live Twitter updates does. Of course, it’ll be noisier still as the week progresses…

Fun fact: I’m actually Jewish, but Hanukkah doesn’t generate quite the same buzz for some reason.

## SI units: because 9,192,631,770 is such a round number

(Click for full 1024×768 image)

Note: The kilogram is technically defined only from the ridiculous lump of metal in a vault in France. The thing with water is the traditional, imprecise definition, but I included it for the sake of explanation (maybe the second’s definition as a fraction of a day should be in there, but ah well.) I used the American spelling of

“meter”, but the quotes (both from Wikipedia) use the official international spelling.

Interestingly, the main complaint with the SI system seems to be that “amount of substance” isn’t a proper physical quantity.

What’s the matter, guys? I thought you liked arbitrary big numbers?

Hmm. I should note, too, that it’s still a far better system than anything else out there, before the powers-that-be force me to use Furlong/Firkin/Fortnight instead.

I want a t-shirt with “Fuck the International Prototype Kilogram”.

## Chickens, turkeys and raptors, oh my!

Take a look at this graph: (via Google: Insights for Search, slightly modified)

Which bird wins? Well, the chicken (red) has the best overall search volume, but Thanksgiving pushes turkeys (blue) right up to the top.

This makes sense. Thanksgiving is more closely associated with turkey than with gratitude.

But what of that yellow line? Raptors deserve more attention. I tell ya, birds these days got no respect for their heritage.

Just imagine if xkcd used chickens.

(from xkcd)

(chicken from Wikimedia Commons)