Morality, Religion & Philosophy: March 2003 Archives
One of my friends asked a question about the number of people who get married. I consulted the source of all knowledge, The Internet, and found this page. It cites reliable sources, but otherwise I can't vouch for its accuracy. Nevertheless, let's look at some of its statistics:
- Median duration of marriage (1997): 7.2 years
- Likelihood of new marriages ending in divorce in 1997: 43%
- Adults between 25 and 34 years old never married in 1998: 14 million (35%)
- Percentage of population (by area of US) who had never married in 1999: Midwest: 28%, Northeast: 28%, South: 26%, West: 29%
- People (by gender) 15 years of age and over who have never married: Males: 32,253,000 (31.3% of men), Females: 27,763,000 (25.1% of women)
- Median age at first marriage: Males: 26.8, Females: 25.1
- Average age of marriage [first marriage and later] in 1997: Males: 28.7, Females: 25.9
- Percentage of people that married under the age of 20 who eventually get divorced as of 1995: 40%
- Percentage of people that married over the age of 25 who eventually get divorced as of 1995: 24%
- Percentage of women whose parents were divorced who get divorced within 10 years as of 1995: 43%
- Percentage of women whose parents stayed together who get divorced within 10 years as of 1995: 29%
- In 1996, children of divorce were 50% more likely than their counterparts from intact families to divorce.
- Fatherless homes account for 63% of youth suicides, 90% of homeless/runaway children, 85% of children with behavior problems, 71% of high school dropouts, 85% of youths in prison, well over 50% of teen mothers.
All very interesting. Waiting until after age 25 to get married seems like a good idea. It's also scary that children who have divorced parents are 50% more likely to get divorced themselves.
Also via GeekPress, an article in the Economist that discusses evolving cooperators and 'punishers' as a solution to the free-rider problem. On the most basic level, the free-rider problem arises in situations where groups of organisms are cooperating for the common good, and a few members of that group cheat the system by taking advantage of the cooperation without giving anything back to the group. The problem is also known as the Tragedy of the Commons, meaning that any resource that is held in common by a group will tend to be abused by individuals rather than used in a coorperative manner, because there is just too much short-term advantage to cheating the system.
Anyway, back to the Economist article. I'm working on my PhD in artificial intelligence, and so I have quite a bit of experience with evolutionary systems such as the one described in the article. I haven't yet read the entire paper in the Proceedings of the National Academy of Sciences, but based on the description in the article, I can't see how their model could achieve cooperative punishment as an emergent phenomena. The author of the paper, Robert Boyd, is a professor at UCLA, so I think I'll email him about it (after I read the paper, of course).
(Update)
The paper can be found here.
It's pretty interesting. The formulas the author gives are satisfying, but in his discussion section he states that the punishers never do reach a stable equilibrium frequency, which is what I would expect given that they will always be at a disadvantage to the meta-free-riding cooperators. I emailed the Robert Boyd to ask for clarification, in case I am mistaken.
