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Old 2012-09-02, 06:33   #11
Basketry That Evening!
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"Bunslow the Bold"
Jun 2011
40<A<43 -89<O<-88

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Originally Posted by rcv View Post
@Walter: If my comments didn't help, then will you please make clear exactly what second derivatives are changing sign. Use specific numbers from published tables and *show us* the second derivatives that are changing.
I'm pretty sure this is what he meant. He didn't say it wasn't
Originally Posted by Dubslow View Post
No, he means this: Take, e.g., B1:

5e4 -- ratio to previous 4.5
25e4 -- ratio to previous 5.0
1e6 -- ratio to previous 4.0
3e6 -- ratio to previous 3.0
11e6 -- ratio to previous 3.67
43e6 -- ratio to previous 3.91

If you plot those ratios, the second derivative (which should be zero) swings from positive to negative and back, without every really settling at zero.

The same thing happens with necessary curves -- the ratio changes for each digit jump.

I've actually had this same question myself more than once (which is probably why I understood him).
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