# Linear Regression Through a Point

#### timmo567

##### New Member
Hi Everyone, I'm trying to find the slope of the regression line with the least squares fit which passes through a certain point $$(x_0,y_0)$$

The equation for my line is $$y=a(x-x_0)+y_0$$ so that at $$x=x_0, y=y_0$$ as required.
I can find the slope if the line equation is the standard $$y=ax+b$$ using the formula given here (for $$\hat{\beta}$$) http://en.wikipedia.org/wiki/Simple_linear_regression but I am unsure how to go through the same steps for the form of $$y$$ which I require.

From that wiki page, the slope of the standard $$y=\hat\beta x+\alpha$$ is $$\hat\beta = \frac{ \sum_{i=1}^{n} (x_{i}-\bar{x})(y_{i}-\bar{y}) }{ \sum_{i=1}^{n} (x_{i}-\bar{x})^2 }$$ where $$\bar{x} \mbox{ and } \bar{y}$$ are the mean of all $$x_i \mbox{ and } y_i$$
I'm hoping to find a similar equation for my form of $$y$$ ($$y=a(x-x_0)+y_0$$) where $$(x_0,y_0)$$ is the coordinate which the best fit line must pass through.

Thanks for any help, Tim