Find Least Squares Regression Line I have a problem where I need to find the least squares regression line. I have found $\beta_0$ and $\beta_1$ in the following equation
$$y = \beta_0 + \beta_1 \cdot x + \epsilon$$
So I have both the vectors $y$ and $x$.
I know that $\hat{y}$ the vector predictor of $y$ is $x \cdot \beta$ and that the residual vector is $\epsilon = y - \hat{y}$.
I know also that the least squares regression line looks something like this $$\hat{y} = a + b \cdot x$$
and that what I need to find is $a$ and $b$, but I don't know exactly how to do it. Currently I am using Matlab, and I need to do it in Matlab. Any idea how should I proceed, based on the fact that I am using Matlab?
Correct me if I did/said something wrong anyway.

First define 
X = [ones(size(x)) x];

then type
regress(y,X)


Observations: 


*

*the first step is to include a constant in the regression (otherwise you would be imposing $a=0$).

*the output will be a vector with the OLS estimates $(a,b)$.
