# Regression equation

• Jul 22nd 2009, 03:03 PM
Swift
Regression equation
I need to find the regression equation but I dont know how to find it, I have x & y values from the scatter graph that I have already produced. The exact thing its looking for is " Find the regression equation. State it in terms of the costs and the output. Give numerical values correct to three significant figures." If anybody could help me at all I would be greatly appriecated I am only really looking for the equation to work it out not for someone to just give me the answers.

+rep asual for people who are willing to help

I thank you all in advance.
• Jul 22nd 2009, 03:21 PM
masters
Quote:

Originally Posted by Swift
I need to find the regression equation but I dont know how to find it, I have x & y values from the scatter graph that I have already produced. The exact thing its looking for is " Find the regression equation. State it in terms of the costs and the output. Give numerical values correct to three significant figures." If anybody could help me at all I would be greatly appriecated I am only really looking for the equation to work it out not for someone to just give me the answers.

+rep asual for people who are willing to help

I thank you all in advance.

Hi Swift,

You might find this site useful if you're talking about simple linear regression.

Learn Simple/Linear Regression tutorial, definition, example, formula

Are you using a graphing calculator or are you trying to do this manually?
• Jul 22nd 2009, 03:23 PM
Swift
Manually and I guess I am doing linear regression as it doesnt state any specific linear....
• Jul 22nd 2009, 03:27 PM
pickslides
• Jul 22nd 2009, 03:33 PM
Swift
• Jul 22nd 2009, 03:43 PM
masters
Quote:

Originally Posted by Swift

Can't you follow the example in the link I gave you. It provides a table of sample x and y values and proceeds to determine the equation of the line of best fit? Be more specific.
• Jul 22nd 2009, 03:45 PM
Swift
Maths Calculator - Regression - Calculation, calculate regression, Simple/Linear Regression is that cheating? as it would be more simple for me because the link you sent me I just cant undertstand what actually is the regression equation (possibly more than one) I am very new too this level of maths still.
• Jul 22nd 2009, 04:44 PM
pickslides
Yes that would be cheating if you are expected to find it manually. Doing the calculations by hand gives you a greater understanding of the process and meaning.
• Jul 23rd 2009, 10:00 AM
Swift
Ok I am working this out with pen and paper just came to a snaggle with this working out.... I bet its straight forward but I just cant work it out what are the first scores :s

The example is here; Learn Simple/Linear Regression tutorial, definition, example, formula (step3)

ΣX = 311 on this example so how does ΣX2 = 19359

ΣX2 = Sum of Square First Scores
• Jul 23rd 2009, 03:55 PM
masters
Quote:

Originally Posted by Swift
Ok I am working this out with pen and paper just came to a snaggle with this working out.... I bet its straight forward but I just cant work it out what are the first scores :s

The example is here; Learn Simple/Linear Regression tutorial, definition, example, formula (step3)

ΣX = 311 on this example so how does ΣX2 = 19359

ΣX2 = Sum of Square First Scores

Hi again Swift,

In step 2 of the example you have a table with columns labeled "x", "y", "x*y", and "x*x".

Step 3 is just the sum $\left(\sum\right)$ of those columns. $\sum x*x$ is, in fact, 19359. I just checked it.