Pay Your Weight to Fly

Our recent Freakonomics Radio podcast “100 Ways to Fight Obesity” looked at some of the social costs of America's increasing rate of obesity. One airline in Samoa is experimenting with defraying some of those costs. It will soon start charging passengers by the kilogram. From The Sydney Morning Herald

Samoa Air has become the world's first airline to implement "pay as you weigh" flights, meaning overweight passengers pay more for their seats.

"This is the fairest way of travelling," chief executive of Samoa Air, Chris Langton, told ABC Radio. "There are no extra fees in terms of excess baggage or anything – it is just a kilo is a kilo is a kilo."

An App for Names

Our latest Freakonomics Radio podcast is called "How Much Does Your Name Matter?" A listener named Mark Edmond wrote in to tell us about Nametrix, a names app he created:

I'm a new dad who was researching baby names and whipped up an app in spare moments over the last year that tells you stuff like this:

It turns out that Ellen is a disproportionately common name for:

  1. psychotherapists
  2. librarians
  3. activists

Ellens also overwhelmingly lean toward the Democrat party and have tended to be most popular in the northeastern part of the U.S.

You can also see names ranked within professions, e.g., these are the top three names for guitarists:

  1. Trey
  2. Rusty
  3. Sonny

I have no idea how good Nametrix works on these dimensions. Having seen a lot of bogus names "data," I am always a bit leery -- especially because it is easy to mistake certain naming patterns for destiny while ignoring the more basic indicators like age, income, education, race, etc. I asked Mark how he assembled his data; here's his reply:

A Rental Car Puzzle

Have you ever noticed that whenever you rent a car, when they give you the keys to the vehicle, there are always two sets of keys?  But the two sets of keys are attached to the same key chain, and no matter how hard I’ve tried, I have never figured out a way to detach one set of keys from the other.

What could possibly be the point of giving customers two sets of keys that can’t be separated?  The downside is that if the keys get lost, two sets of keys are gone.  Also, the keys are much bulkier in my pocket than otherwise would be the case.

The only possible explanation I can see is that since no one carries around two attached sets of keys to the vehicle they own, people are less likely to confuse their own car keys with those of the rental vehicle.  It just doesn’t seem like that could be the logic, however.

So can anyone explain to me the real reason rental car companies do this?