Summary in haiku form
Responsiveness to changes.
How much do you stretch?
Summary in one paragraph
Elasticities measure responsiveness, e.g., the price elasticity of demand measures the percentage change in quantity demanded produced by a 1% increase in price. (More generally, the X elasticity of Y measures the percentage change in Y produced by a 1% increase in X.) Like a rubber band, more elasticity corresponds to greater responsiveness.
Notes on specific pages
Elasticity formula
Laffer curve
Elasticities and monopoly revenue
