On 29/12/2012 13:01, Norman wrote:
Nick Gardner wrote:

I thought that you always round up if 5 or greater, i.e., 15.15 will always
become 15.2, and so on.

I have not heard of any other way of doing this (until now).

The standard meteorological method is to "throw it to the odd". Therefore,
15.15 becomes 15.1 whereas 15.25 becomes 15.3. I believe the logic in this is
to eliminate systematic bias that would be caused if rounding was always up (or
down).

.... indeed: I've not found a way to do this in Excel and I have to keep
manually checking so as to over-write the automatic calculation it
offers. As noted above, in meteorological statistical use, as far as I
know, we've always 'thrown to the odd'.

The only deviation to this was with actual pressure observations (not
climatological returns) where 0.5mbar was always thrown *down*: this
being 'safer' when setting altimeters etc.

Martin.


--
West Moors / East Dorset
Lat: 50deg 49.25'N, Long: 01deg 53.05'W
Height (amsl): 17 m (56 feet)
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