# Least Squares

1. Jan 29, 2012

Hello,

What are the error bars on the least squares fit line?

recall the variables are:
x ; y ; x^2 ; xy ; y^2 ; yi=mx+c ; d =(y-yi) ; d^2

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is it d?

Thanks

2. Jan 29, 2012

the answer is: $\sigma_y^2 = \frac{1}{N-2} \times \displaystyle \sum_i^N (y_i - A - Bx_i)^2$