Price Elasticity of Demand

A coefficient that represents the relationship between a chance in price and any consequential change in demand.

Expressed as:

Cross Price Elasticity of Demand

Similar to price elasticity of demand, but represents the change in quantity of an alternative or substitute product as a consequence of change in price of another.

Expressed as

Investopedia Reference

For example, an increased price in my product portfolio might result in my customer choosing to buy a competitor product, or a slightly cheaper product of my own (cannibalisation).