It's hard to measure how happy people are with their society, but such a measure would be useful both for directing policy and in aid work. One approach is the GNH or "Gross National Happiness" system which rates sustainable development, cultural integrity, ecosystem conservation, and good governance positively. Other rough approximations are the fraction of people living above some consumption level (more than $1 per day) or the equality level. All of these have the problem that outside groups are saying "these are the things that we value, so we will estimate your happiness by how much of these things you have". The other direction, just asking people how happy they are, gives you the problem that one person's "very happy" might be another person's "satisfactory". Worse, culture plays into this strongly, with some cultures looking more negatively on complaining than others, so we might decide that country X is worse off than country Y just because country Y's people are less willing to admit to unhappiness.

Another approach, described as Quality of Life Island involves people indicating how willing they would be to leave their society for a specific alternative 'island'. The idea is that the more willing you are to leave then the worse your society must be. Briefly:

Then random people and families from around the world could be asked for their cutoff island quality of life, the level they would require to move to the island. If this quality was less than a previously randomly generated quality offer, they would actually move to the island. These quality values could then be the data on which to base a better estimate of quality of life around the world and across time. To maximize the amount of this data, at perhaps some sacrifice in quality, one could ask larger groups for their cutoff value, but only actually make the pre-generated offers to a small random subset.

While I like the idea of having people make choices, I don't think this works at all. As a person in any society, I either would rather move to the island, or rather not move. If I pick 0% happy, I move. If I pick 100% happy I don't move. Why would I choose anything in between? I don't actually think this is a crucial flaw, however, as you could just ask a random sampling of people whether they would like to move or not, and then your happiness level is the fraction saying they would not like to move. Because we're working with binary data, we do need to ask more people in each society to get good numbers, though.

While it's pretty expensive to actually move people, immigration does give you an approximation of this measure. That many more mexicans want to move to the usa than the reverse indicates that the quality of life in the usa is better than in mexico. That people are leaving the usa's northeast for the south and west indicates something similar.

Update 2010-06-02: The author responded to a question by email to tell me that he meant that the people choose amounts of money. Which makes a lot more sense, and gives you non-binary values.