Page 261 - F2 - MA Integrated Workbook STUDENT 2018-19
P. 261
Statistical techniques
3.1 Using Linear regression
Linear regression calculates a straight line relationship between the variables (y = a +
bx) as follows:
a = y ̅ − b x ̅
n∑xy – ∑x∑y
b = ———————
2
2
n∑x – (∑x)
where n = number of observations
x and y are the arithmetic mean (or average) of x and y and are calculated as:
̅
̅
∑x ∑y
x ̅ = —— y ̅ = ——
n n
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