Means Rules- help and advice

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darrog
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Re: Means Rules- help and advice

Post by darrog » Fri Jan 04, 2013 2:05 pm

I did previously mention this:

So how do you work out seasonal and yearly averages then?

A - the sum of the mean temps divide by 12 and then apply those rules re 0.05, 0.15, etc or

B - the sum of the mean min/max divide by 2 and then apply the above rules?


But there is a C and 2012 as provided an example of when it matters!

using A my yearly mean is 8.24c - gets rounded down to 8.2c
using B my yearly mean is 8.25c - gets rounded up to 8.3c

And at this point I did think that if a monthly temp is calculated by B, then it should follow that a yeraly mean should be calculated the same way (and not use A)

But I now expect you all to use C which is the only true way - but takes a little more time!

C - is the total of all 365/6 min' temps + the total of all the 365/6 mean max' temps divide by 730/732

And guess what - using C my yearly mean is 8.26c - rounded up to 8.3c

I now expect you all to check and if necessary revise all your data!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Darren Rogers - he who submits the most interesting posts, AKA Mr Data
Maulds Meaburn

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Paul C
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Re: Means Rules- help and advice

Post by Paul C » Fri Jan 04, 2013 8:19 pm

:o

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Paul C
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Re: Means Rules- help and advice

Post by Paul C » Fri Jan 04, 2013 8:26 pm

Totally confused now Darren

But I,m sure it should work out the same ?

here are mine attached
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darrog
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Re: Means Rules- help and advice

Post by darrog » Sat Jan 05, 2013 12:40 pm

Paul - it's simple really and also obvious.

you use all 30/31 min temps in a month to calculate a mean min and then ditto for the mean max - you now add them all together.
then use that totals and divide by 60/62 to calculate your mean temp for the month - then 'throw to the odd' if necessary.

To calculate the yearly mean min/max and then mean is just the same, but now instead of 60/62 numbers you have 730/732.
Darren Rogers - he who submits the most interesting posts, AKA Mr Data
Maulds Meaburn

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darrog
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Re: Means Rules- help and advice

Post by darrog » Sat Apr 06, 2013 1:01 pm

I'm going to have to amend this really.

after March threw up another oddity (a mean min of -1.6c and a max' of 4.9c = 1.65c which should be thrown to the odd of 1.7c - why did my spread sheet show a mean of 1.6c - answer was that the 62 min/max readings actually = 1.6489c - so it rounded it down!!!

So anyway, Philip Eden tells me that he always quotes his figures to two decimal points and which really is quite logical.

so from now on i will quote my mean to 2 decimal points - so March 2013 is obviously 1.65c

now going through the process of changing back all my other months to two decimal places - quite easy really as i had done 50% of them that way anyway
Darren Rogers - he who submits the most interesting posts, AKA Mr Data
Maulds Meaburn

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