In article 2010120908504475249-taharley@dundeeacuk,
Trevor Harley writes:
On 2010-12-08 20:10:13 +0000, Teignmouth said:

John,
If I use the SKEW function I get the following values:
Period Jan Feb Mar Apr May Jun Jul Aug
Sep Oct Nov Dec
1659-2009 (0.6) (0.5) (0.1) (0.1) 0.1 0.2 0.4 0.3 0.0 (0.1) 0.0
(0.2)
1971-2009 (0.8) (0.8) (0.2) 0.2 (0.1) (0.2) 0.8 0.4 (0.1) 0.0
(0.1) (0.8)
Now what do I do with the value and the Standard Deviation?
If I have a December mean for the period 1659-2009 of +4.1c, and the
STDEV is 1.7c, and the SKEW is -0.2c, do I get a revised STDEV of 1.5c
or 1.9c? Then do I use +4.1c and the revised STDEV x1 x2 x3 etc to
get the revised Standard Deviation thresholds?
Your help is much appreciated.
Thanks

No, just use the standard deviation. The skew is tiny. It's as good a
normal distribution as you'll ever get.

Surely a skew of -0.8, as for Decembers over the last 40 years, is
enough that it ought to be taken into account? It's interesting that the
winter month skew values have been larger over the last 40 years have
been larger that when one considers the whole CET record.

snip
--
John Hall
"I look upon it, that he who does not mind his belly,
will hardly mind anything else."
Dr Samuel Johnson (1709-84)