Anybody good with Sigma and graphs ?

[ElectroNewby]

I have a hard time figuring ∑ in the equation to find B and A
y = ax + b

The teacher was too fast on the chalkboard, I would just note the formula without understanding.

 

[squishy36]

I have no clue what your question is. Do you want to find the parameters of a linear equation by regression? If so, go find a copy of Neter & Wassermann "Applied Linear Statistical Models", Irwin, 1974. It's a superb book and gives you the requisite equations, derivations, and examples. I've looked at a lot of statistics books over the decades and I still consider this one of the best.

BTW, the reason I was using it was to do some quickie multiple linear regression in python. Using numpy, you can do so in just a few lines of code (or use scipy, where it's already built in). Printing out an ANOVA table and residual table is not much extra work.

 

[MrAl]

Hi,

Sounds like a least squares regression problem to me too.

 

[ElectroNewby]

thank you I might check fort that book
it's 100$ on amazon

 

[MrAl]

Hello again,


You dont really have to buy a 100 dollar book to understand the regression for that simple equation you posted, unless of course you are also very interested in more advanced regressions too. For the one you posted, we could do that here im sure, if that's what you are after of course.

 

[ElectroNewby]

Yes if you want to !

I'll be attacking the problem during next week during the mid-school week off, I have some revision to do but at the same time a few subjects (presently doing matrix). Time is an issue and also sleep deprivation atm lol

I want to understand the regression lines and how sigma works once for all. I have a good idea but not in depth

thank you for your time

 

[DerStrom8]

You mention you have a hard time finding sigma in the equation, but the only equation you give is the standard line formula (y=ax+b). I assume there's more to the problem. Could you post that as well?

Good luck!
Der Strom

 

[squishy36]

thank you I might check fort that book
it's 100$ on amazon

Good Lord, don't buy a $100 book, borrow it from your library -- they'll get it on ILL if they don't have it locally. Besides, virtually every basic statistics book available will have the equations you need (and, of course, they're easy to find on the web). Or, if you're desperate, lemme know here and I'll post them in a PDF for you.