New to Stats, Can someone help me out?

[cm1395]

Hey everybody! Im fairly new to that statistics world so please forgive me in advance. If I have the same x-value and two y values: One y value being the measured and the other being the calculated. How to I compare the two line plots using stats? Essentially how do I explain how the measured line plot compares to the calculated? Thank you for any advice.

[HiOctane]

common way is to take each distance [y-y'], square each one of these and then sum the squared values. that will give you some number called the sum of square errors. the smaller that number is, the better the approximated line is to the actual.

other methods include taking absolute value of the distances |y-y'| or attaching weights to the square errors.