Formulae sheet
1 Regression analysis
y = a + bx
a = (∑y ÷ n) − (b∑x ÷ n)
b = (n∑xy − ∑x∑y) ÷ (n∑x2 − (∑x)2)
r = (n∑xy − ∑x∑y) ÷ √[(n∑x2 − (∑x)2)(n∑y2 − (∑y)2)]
2 Learning curve
Y = axb
Y | cumulative average time per unit to produce x units |
a | the time taken for the first unit of output |
x | the cumulative number of units produced |
b | the index of learning (log LR/log2) |
LR | the learning rate as a decimal |
3 Demand curve
P = a – bQ
b
a = price when Q = 0
MR = a – 2bQ