Regression Modeling

 Linear Model 

In a linear model, the mathematical formula that models the data is Y= mX +b. This formula tells you that for any value X, you calculate the Y value by multiplying the X by a constant m and then adding another constant b. The value m is called the line's slope, and b is the Y intercept (the value of Y when X = 0). This formula gives a perfectly straight line, and real-world data doesn't fall exactly on such a line.  The point is that the line, called the linear regression line, is the best fit for the data. The constants m and b are different for each data set. (1)

(1) Provided by Microsoft Excel Formulas & Functions for Dummies/Ken Bluttman pg 210