When you don't have enough to cover all your bills and keep appliances up, your spending patterns change dramatically as well. If you don't have a functioning fridge, you're only buying a tiny (extremely overpriced) package of meat. If you don't have gas for your oven, you're only going to be making things in the microwave.

This is discussed in numerous really interesting ways in "Makers" by Cory Doctorow: http://craphound.com/makers/download/

There're also some perverse incentives around happiness calculations too. When I was in college, I had a netfriend who lived in a poor rust-belt town, and her family never had enough to eat. One time she was talking about her brand new DVD player and home entertainment system, a couple days after talking about how there was no food in the house. I asked her why she'd just bought a brand new DVD player (something that, to my middle-class college existence, was an incredible luxury) when she was going hungry.

She replied that if she'd spent that money on food, she'd eat well this month but would just go hungry again next month. This way, she'd go hungry all the time, but at least she could lose herself in a movie and forget about it. There's a peculiar kind of logic to that which I can't really argue with, despite the common Internet refrain about how poor people are poor because of their own stupidity.

We came across something similar to this when we were researching credit unions and pay-day lending. One of the reasons that people on benefits here can't access cheaper fuel bills is that they have difficulty planning their finances on a monthly basis when given a fortnightly lump of money. I can't remember the exact figures - I think it worked out as something like £5 a month they were losing. Which when you multiply it up for thousands of people or significant stretches of time is fairly significant - more or less what some people are getting into debt over, multiplied by a year, for people borrowing money to cover Christmas for instance.

Rice costs $.20 for 1300 calories.

Rice can be incredibly unhealthy for you as well...my girlfriend talks about the "Peace Corps 15", where your host family stuffs you full of incredibly starchy carbohydrates (because that's often all that's available in 3rd world countries) and you end up gaining a large amount of weight and ending up with nutritional deficits anyway because of it.

I wouldn't recommend you eat 1300 calories of rice per day. But for calibration purposes, it's useful information I think.

Think more along potatoes and quark.

You get 6 apples per big Mac. It is actually a better meal.

6 apples: 600 kcal. A full day's worth of fiber, vitamin C, and sugar. But not much else. No protein or fat to speak of.

Big Mac: 600 kcal. Half a day's worth of fat, protein, and sodium. 12% RDA of fiber, 30% of calcium, 25% iron.

If you could only eat one or the other, you'd probably be better off with the Big Mac. If you wanted to turn these two poor choices into a full day of three meals, you should probably eat two Big Macs and 6 apples (plus lots of water, and hopefully a vitamin supplement).

Poor people don't buy Big Macs, they load up on dollar menu double cheeseburgers / McDoubles to maximize calories+nutrition per dollar. And the burgers are a better nutritional bet if you're poor.

no it isn't. its a terrible "meal."

delusions are not your ally. try not to embrace them with such zeal.

Well, I imagine so. The calorie-per-dollar ratio for apples is negative.

I don't think this is true. According to this table a large apple has more than 100 calories: http://calorielab.com/foods/apples/62

Erm...what? I don't understand. Calorie-per-dollar ratio = p/q for p calories and q dollars. What model are you using where p or q but not both is negative for the apples example but not the BigMac one?

Have you ever eaten a dollar? Those things just don't fill you up.

Hahaha, "for p calories [in the food] and q dollars [cost of the food]" is supposed to be implied but I like your quip!

To digest an apple it takes calories. Yes, an apple has around 100 calories (depends on size) but the net value can be negative.

Celery is the classical example of this.

Might want to check up on this. http://en.wikipedia.org/wiki/Negative_calorie_food

That's very interesting

The thing is, the digestion calories are one small portion of the dietary effects of any food.

For example, some increase thermogenesis, so you could account for that

Yes, apart from cold water it seems hard to think any food can provide no calories. Evolution took care of our digestive tract extracting the most of food (unless you're eating paper)

I'm certain that apples do not fall into the negative calorie category of celery, cress, etc. but it's still a possible answer to the "what model" question, so thanks. I guess that's what "Filligree" was going for...

Apples and other fruits are full of fructose (sugar). How the hell are people suggesting that they take more calories to digest than they contain?

Disregarding biology, an apple has .15 kg * (c^2) -> cal = 3.2 × 10^15 calories

How can it be negative? Do you mean less than 1?