R help - Jul 2008 - Fitting a curve to data

Hi

I have a set of data like this:

    *Time of Day* *Pct of Daily Volume* 9:45 7.50% 10 6.25% 10:15 4.45%
10:30 4.80% 10:45 4.45% 11:00 4.20% 11:15 2.50% 11:30 2.30% 11:45 2.25%
12:00 2.45% 12:15 2.60% 12:30 2.00% 12:45 2.05% 13:00 2.40% 13:15 1.90%
13:30 3.10% 13:45 2.90% 14:00 2.80% 14:15 2.50% 14:30 3.40% 14:45 4.40%
15:00 5.40% 15:15 4.00% 15:30 4.70% 15:45 6.20% 16:00 8.50%

I want to fit a curve to the data and get the best function fitted,
therefore I can calculate the integral of the function.
How can I do that?

Thanks,
Shirin

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?lm
lm(x[,1]~x[,2])

On Tue, Jul 1, 2008 at 2:28 PM, Shirin Safa <sh.safa@gmail.com> wrote:
> Hi
>
> I have a set of data like this:
>
>    *Time of Day* *Pct of Daily Volume* 9:45 7.50% 10 6.25% 10:15 4.45%
> 10:30 4.80% 10:45 4.45% 11:00 4.20% 11:15 2.50% 11:30 2.30% 11:45 2.25%
> 12:00 2.45% 12:15 2.60% 12:30 2.00% 12:45 2.05% 13:00 2.40% 13:15 1.90%
> 13:30 3.10% 13:45 2.90% 14:00 2.80% 14:15 2.50% 14:30 3.40% 14:45 4.40%
> 15:00 5.40% 15:15 4.00% 15:30 4.70% 15:45 6.20% 16:00 8.50%
>
> I want to fit a curve to the data and get the best function fitted,
> therefore I can calculate the integral of the function.
> How can I do that?
>
> Thanks,
> Shirin
>
>        [[alternative HTML version deleted]]
>
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-- 
Let's not spend our time and resources thinking about things that are so
little or so large that all they really do for us is puff us up and make us
feel like gods. We are mammals, and have not exhausted the annoying little
problems of being mammals.

-K. Mullis

	[[alternative HTML version deleted]]

I think the previous answer (to use lm() ) is not necessarily the best 
option.

Since what you want is the definite integral (area under the curve), you 
can just use one of the existing definite integration tools (sorry, I 
don't recall the names because I don't use them).

If you want to get a "smoothed" curve to remove errors in your data 
points,  I'd recommend fitting a spline and integrating under that.