you could always post it if you want our help

What the HELL is Standard Deviation Oo

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There is no Silicon Heaven! But where do all the calculators go ?

You could no more evade my wrath... than you could your own shadow!

@grom: I don't need help, I just need some kind of Data processing machine to go through all this data

@Heltak: Once you find out, you'll wish you hadn't

ugh, I hate statistics sooo much. I don't know if any of you guys are doing A-level maths because believe me, standard deviation is the least of your worries. I've done stats up to the S3 module. Try poisson to normal distribution approximations, t-tests for small samples with known distributions, hypothesis tests and type 1 and 2 error probablities
Think of standard deviation as the average difference that each piece of data has from the average value. ie it's a kind of measure of how dispersed the data is.
The problem with stats is that you lose all perspective of what you're actually doing. At least with things like mechanics you can form a mental image of what's happening.

@recusant I did maths with stats too...*shudder* thanks for all of the memories *shudder*

@aceaz fair enough, just thought we could help thats all...

I have knowledge of SG Standard Deviation, it has some odd forumla I forget but requires thje average + something

-~-~-~-~
There is no Silicon Heaven! But where do all the calculators go ?

You could no more evade my wrath... than you could your own shadow!

So, on a boredom/depression scale of 1 - 10, one being sleepy and ten being slit-your-wrists, what score does this get. (We're doing moving averages at the moment, such fun, which gets 5, because it's very easy, but horribly repetitive)

I'm not evil, just morally challenged

sadly I actually enjoyed maths at school...hence why I took the a-level...but the a-level is definitely a completely different ball game...its about 5000% harder. A very scary jump.

Anyway, there's nothing wrong with a little deviation now and again is there?!!

I'd give it about a 7, because although the work as it is is not hard, there is merely an obsene amount of data for me to get through.
The only thing thats really annoying me is that I'm not even doing Maths at A-Level, but I still have to get a good grade in this in order to get a decent average to get into sixth form. Only about four months of secondry school left now...

I can count and write my own name.

(I hate maths, i just can't do it, I'm 100% reliant on calculators. i can't even do long division)

isnt standard deviation just 10 to the power of x?


"Ambition makes you look pretty ugly.
Kicking, screaming, gucci little piggie"

Standard Deviation-

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A measure of the range of values in a set of numbers. Standard deviation is a statistic used as a measure of the dispersion or variation in a distribution, equal to the square root of the arithmetic mean of the squares of the deviations from the arithmetic mean.

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No, I do't get it either
Just informing you that I've alomost finished this thing. Couple more graphs and then I'm finished. Finally!

Edited by - Aceaz on 2/22/2004 2:42:29 PM

Standard Deviation...ok, try to think about it this way....its all to do with statistics. Lets say we were doing a study into how many drinks the average Brit drinks on a saturday night....easy enough to associate with? Ok, so we go out and ask people how much they drank on saturday and plot it on a graph...this is were you have to use your imagination....on the x axis we put number of pints, and on the y axis we put the number of people who had that number of pints. With me? Ok, what you'll find is that the graph peaks around an average like this....



If that peak is at say "5 pints", then we can say that the average person drank 5 pints on that saturday night. Make sense? Ok, now, standard deviation. We could re-examine our stats with the "standard deviation formula", and what we will acheive is we will find out what "most people" drank, rather than what "the average person drank". For example, we know that the average person drank 5 pints....but what standard deviation will tell us is that MOST people drank between 3 and 8 pints. Get it? So if we were to plot the graph again....



the red area would show the value of standard deviation....lets say for arguments sake, 70% of the population....the red together with the green area would show us two standard deviations, lets say totalling 85% of the population....and the red, green AND blue areas would show us three standard deviations, effectively accounting for 98% of the population. The other 2% would be people who drank nothing and people who drank ridiculous amounts (2%=TLR members methinks!)

And its as simple as that! So why do we want to find standard deviation? Well its all to do with companies etc that rely on statistics. If this drinking survey was done in every town in the country, you would be able to calculate how much each town "deviates" from the national average....to find out things like "the most drunk town in britain" or scarily "the most sober town in britain"...you'd even be able to work out which town is the most "average" by looking at the town, wait for it, with the lowest standard deviation.

Get it? No? Well I'm not explaining it again!!

i got lost after the drinking bit. You're hurting my head, I hate maths, and the graphs hurt my eyes.