Derek Thompson for The Atlantic on how retail uses our numeric biases to their advantage:

Now that I’ve just told you that consumers try to avoid additional payments, I should add that there are two additional payments we love: rebates and warranties. The first buys the illusion of wealth (“I’m being paid money to spend money!”). The second buys peace of mind (“Now I can own this thing forever without worrying about it!”). Both are basically tricks. “Instead of buying something and getting a rebate,” Poundstone writes, “why not just pay a lower price in the first place?’

“[Warranties] make no rational sense,” Harvard economist David Cutler told the Washington Post. “The implied probability that [a product] will break has to be substantially greater than the risk that you can’t afford to fix it or replace it. If you’re buying a $400 item, for the overwhelming number of consumers that level of spending is not a risk you need to insure under any circumstances.”

Other tidbits: our obsession with prices ending with a nine and how we justify purchases of things that are more expensive but aren’t necessarily better than the cheaper item.

WNYC mapped all street stops that resulted in the recovery of a gun, based on data from the New York police department. On top of that, the green spots, they mapped areas where police search more frequently.

Mayor Michael Bloomberg and Police Commissioner Raymond Kelly argue the main purpose of stop-and-frisk is to get guns off the street. Out of more than 685,000 stops in 2011, about 770 guns were recovered. That means about one tenth of one percent of all stops result in the seizure of a gun.

But those guns are not showing up in the places where the police are devoting the most stop-and-frisk resources.

I’m sure a lot of people’s initial reaction to this map went something like this: “Psh. The police don’t have a clue what they’re doing,” which was one possibility the article suggested. The other was that the stops are working as a deterrent.

What’s more likely: Police officers have managed to end up in almost every area where there are fewer guns (and missed where there are more guns), or people with guns avoid the areas where there are a lot officers? I’m gonna go with the police point of view on this one.

Love is complicated. It twists, it turns, and sometimes it smacks you in the face so hard you lose track of where and when you are. Artist Louise Ma diagrams these many facets of love and relationships in her ongoing project What Love Looks Like.

[Thanks, Rich]

While we’re on the subject of the web that is Wikipedia, four-man, Baltimore-based development shop Friends of the Web made Wikiweb, an iPad app to research and casually browse Wikipedia. As you search for a topic, an interactive network that shows connected articles appears on the left alongside the current article on the right.

Wikweb: Now even easier to find yourself lost in Joe Pesci trivia.

Brendan Griffen created a giant network of people, using every profile on Wikipedia that had an “influenced by” or “influences” field. Each node represents a person and is sized by the number of links going in and is colored by genre.

It really is fascinating (to me at least) to start at one node and bounce along the connections to a distantly related someone else. People in philosophy influencing fantasy writers who influence comedians. It shows one thing above all: the evolution of ideas is a non-linear process. We too, are somewhere in this web, albeit at a smaller scale. We too, are the sum of many.

Be sure to check out the easier to read and browse zoomable version. Also available in print.

Last week, the Washington Post compared the ages of Olympians, but it only focused on range, so you couldn’t see the variation in between. For example, Dara Torres was 41 at her last Olympics so the bar was stretched to the right even though there were no other swimmers near that age. Plus the Post piece was US-only. So Gregory Matthews took the statistician’s route and box plotted the age of all olympians from all countries.

This barebones layout of course sacrifices the relatability of the first, but it’s easier to see the distributions of each sport and to spot the outliers. Apparently there was an 11-year-old swimmer Yip Tsz Wa at the 2004 games in Athens. Wha?

Kevin Drum on data is or data are:

Now, I know that lots of people continue to foolishly disagree with me about this, but I’m curious how far they’re willing to push things. If you had, say, five bits of information, would you say I only have five data? If you really, truly believe that data is a plural noun, you’d have no problem with this. But does anyone actually do it?

This was in response to the Wall Street Journal’s style guy saying that they can go either way, as the word as has evolved to also mean a singular collection of numbers.

Here’s what the New York Times style guide has to say about it:

[D]ata is acceptable as a singular term for information: The data was persuasive. In its traditional sense, meaning a collection of facts and figures, the noun can still be plural: They tabulate the data, which arrive from bookstores nationwide. (In this sense, the singular is datum, a word both stilted and deservedly obscure.)

I say data is. The plural version sounds weird to me.

Rebecca Rosen for The Atlantic on why maps aren’t the best interface all of the time:

Think of it this way. In the days before online trip planners and GPS, if you wanted to know how to get from point A to point B, you would look at a map and trace out a route. But these days few people would use a map that way (I still do just because I enjoy the process but I think I’m in the minority). Instead, they would plug in their request and an algorithm would spit out a route for them. The route would appear on the map, but the map is no longer the tool for finding that answer.

In other words, just because the data has latitude and longitude attached to it, which seems like everything these days, you don’t need to automatically assume that you should throw it on a map.

Nicolas Rapp, for Fortune Magazine, mapped the underwater cables that make the global Internet possible.

If the internet is a global phenomenon, it’s because there are fiber-optic cables underneath the ocean. Light goes in on one shore and comes out the other, making these tubes the fundamental conduit of information throughout the global village. To make the light travel enormous distances, thousands of volts of electricity are sent through the cable’s copper sleeve to power repeaters, each the size and roughly the shape of a 600-pound bluefin tuna.

I think the theme of this year’s Olympic graphics is how you relate to athletes. In this interactive by the BBC (in Spanish), height and weight of medal winners from the last Olympics in Beijing are plotted against each other. The more red, the more athletes with that weight-height combination, and you can click on a square to see the corresponding athlete(s). The twist is that you can enter your own height and weight to see where you are in the mix.

Combine this with the recent age piece from the Washington Post, and you’ve got a more complete picture. Why stop there though? I want country, gender, and hair color breakdowns. [Thanks, Ben]