Posted by gary (209.187.114.94) on January 05, 2000 at 01:22:52:
A few years back i was surfing up stuff for a relative with cancer and found this WONDERFUL article by Stephen J Gould of Harvard. (Arguably one of the brightest life science minds on earth today).
It is about medical statistics being misinterpreted and misapplied, as much by doctors as anyone else - not because they don't know their medicine, but they don't know what the numerical statements REALLY mean.
To me, the principles involved are applicable to a lot of what we see in CH research reports, and it's real important (I think) not to go running all over the speculative landscape with faulty conclusions based on shallow or false ideas of what all these %s mean and don't mean.
I clipped a couple paragraphs, which follow.
If it sounds like the sort of reading/thinking that interests you, follow the link below to the complete article.
ENJOY! IT'S REAL GOOD JUJU ~~
http://cancerguide.org/median_not_msg.html
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excerpt from The Median is Not the Message, By Stephen J Gould:
We still carry the historical baggage of a Platonic heritage that seeks sharp essences and definite boundaries. (Thus we hope to find an unambiguous "beginning of life" or "definition of death," although nature often comes to us as irreducible continua.)
This Platonic heritage, with its emphasis in clear distinctions and separated immutable entities, leads us to view statistical measures of central tendency wrongly, indeed opposite to the appropriate interpretation in our actual world of variation, shadings, and continua.
In short, we view means and medians as the hard "realities," and the variation that permits their calculation as a set of transient and imperfect measurements of this hidden essence. If the median is the reality and variation around the median just a device for its calculation, the "I will probably be dead in eight months" may pass as a reasonable interpretation.
But all evolutionary biologists know that variation itself is nature's only irreducible essence. Variation is the hard reality, not a set of imperfect measures for a central tendency. Means and medians are the abstractions. Therefore, I looked at the mesothelioma statistics quite differently - and not only because I am an optimist who tends to see the doughnut instead of the hole, but primarily because I know that variation itself is the reality. I had to place myself amidst the variation.