inelastic
income changes and demand does not
elastic
income changes and demand also does
inelastic (#)
elasticity is less than 1
elastic (#)
elasticity is greater than 1
normal good
income and QD both increase/decrease
inferior good
income and QD move in opposite directions
complementary goods
cross-price elasticity is negative
substitutes
cross-price elasticity is positive
example of complements
“batteries not included” (goods bought together)
example of substitutes
“buy this dupe!” (goods bought instead of another)
cross-price elasticity
measure of how much QD responds to the price of another good
income elasticity
measure of how much QD changes when price changes (there is a change in income)