Which trend line?

[Guest]

I need to interpolate some data points. But I am not sure which kind of trend
line should I draw?

There appears to be many different kind..
I do not need a super fanciful one. My main purpose is really to find the
trend (literally) so which one should i use? Polynomial? and also how do i
know how many order? (what is a order anyway?) I am sorry to ask such stupid
questions, but i am a new beginner to advanced charts. I usually only need to
plot simple charts. and microsoft help is not as advanced for idiots like me
=p

 

[joeu2004]

I need to interpolate some data points. But I am not sure which kind of trend
line should I draw?

The question is impossible for anyone to answer without seeing the
data. Usually, the correct trendline to use depends on an
interpretation of the data. And sometimes the correct trendline to use
is determined by the process that drives the data, not the data itself.
For example, some processes are inherently exponential.

My main purpose is really to find the
trend (literally) so which one should i use? Polynomial? and also how do i
know how many order? (what is a order anyway?)

"Order" is the highest exponent of "x" in the formula. For example, if
the formula is x^2-x+1, that is a "second-order" polynomial.

However, beware of polynomial "trend" formulas. It is always possible
to find a polynomial formula that fits the data exactly; simply choose
an "order" that is one less than the number of data points. That is
misleading insofar as it is really not a trend formula at all.

I am sorry to ask such stupid
questions, but i am a new beginner to advanced charts.

It is not a stupid question at all. Trend analysis is an art to some
degree, not a science. In any case, the only stupid question is the
one not asked. There are no stupid questions; only stupid answers.

I usually only need to
plot simple charts. and microsoft help is not as advanced for idiots like me

MS help is not "advanced" enough for anyone, much less people who truly
need it.