In Reply to: Re: There is a slightly problematic problem posted by Monger on May 12, 2005 at 20:52:26:
My comment was about Statistician's assumption #1:
"1) TFI membership has stabilized within a fairly narrow range over 31 years. In 1973 when I was a member, the estimated membership was around 10,000. It's approximately the same now at around 12,000. It might have been higher in the 1980s, but that doesn't matter. There's not a lot of deviation between T1 (1973) and T2 (2004).
"I can drop 1968-1972 from the equation because that four year period represents growth from zero to 10,000 members. This is outer tail of the total distribution over time, and it skews the estimation."
But the assumption that there were 10,000 members in 1973 is wrong.