Posted by Ueli (194.230.29.76) on July 31, 1999 at 17:20:42:
In Reply to: Re: Age, Sex, Race, Twins ???? posted by Todd on July 30, 1999 at 21:54:51:
Hi Todd,
You state "Very few of us, statistically speaking, have immediate family with clusters". Also the 11% of people with CH relatives in the survey is probably a bit high (few people know other CHeads unless they have another one in the family), I cannot agree with your statement.
I wanted to do some calculations, but since my probability theory and statistics knowledge have eroded over time, I had to use the BFBI method. Here what I did:
I took a population of 250 million and split it up into families of 10 (parents, siblings, children). Then I picked at random 1000 people from the whole population and recorded how often a family was hit twice. I did this run 2000 times and guess what, not once came two people from the same family. When I reduced the population size to 100 million an average of 0.025 out of a sample of 1000 came from the same family. With a 25 million population there were 0.167 hits in 1000.
Conclusion: 122 CHeads with CHead relatives out of 1052 in our survey cannot be a chance result, since the population they come from is ways over 250 million.
There must by a family connection, probably genetic, but the hereditary rules must be a bit more complicated than for blue eyes. And remember, it is well known that migraines runs in families and many CHeads reported on the board one or more relatives with migraines.
Pain free nights and days,
Ueli