Understanding Demand Elasticity for Better Market Decisions
Learn about the importance of demand elasticity in market competition and pricing strategies. Explore different types of elasticity and their impact on consumer behavior and market dynamics. Develop a deeper understanding of demand responsiveness for informed business decisions.
Understanding Demand Elasticity for Better Market Decisions
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Presentation Transcript
Chapter 6 Demand and Elasticity A high cross elasticity of demand [between two goods indicates that they] compete in the same market. [This can prevent a supplier of one of the products] from possessing monopoly power over price. DUPONT CELLOPHANE DECISION
Elasticity: Measure of Responsiveness • Price Elasticity of demand • Ratio of • Percentage change in quantity demanded • To: percentage change in price • Responsiveness of quantity demanded • To price changes
Figure 1 Hypothetical demand curves for film Df Ds b a B A Df Ds 0 0 1.5 3 4 4 10 10 $20 $20 Price per package Price per package Quantity demanded Quantity demanded (b) (a)
Elasticity: Measure of Responsiveness • Demand – elastic • 10% rise in price • >10% drop in quantity demanded • Elasticity > 1 • Demand – inelastic • 10% rise in price • <10% drop in quantity demanded • Elasticity < 1
Figure 2 Sensitivity of slope to units of measurement at Paul’s pizza parlor D D $16 $16 15 15 14 14 13 13 12 12 11 11 10 10 9 9 B B A A 8 8 7 7 Price per Pizza Price per Pizza D 6 6 5 5 D 4 4 0 0 2000 2000 2500 2500 3000 3000 500 500 1000 1000 1500 1500 3 3 2 2 Pizzas per week (a) Slices of Pizzas per week (b) 1 1 2880 2240 280 360
Elasticity: Measure of Responsiveness • Elasticity formula • Each change: percentage change • Each percentage change • Average values (before & after) • Absolute value • Price elasticity of demand =
Elasticity: Measure of Responsiveness • Perfectly elastic demand curve • Horizontal demand curve • Infinitely elastic • Perfectly inelastic demand curve • Vertical demand curve • Zero elasticity
Figure 3 (a), (b) Demand curves with different elasticities D “Perfectly inelastic” demand curve “Perfectly elastic” demand curve D D D 0 0 90 Price $0.75 Price Quantity demanded Quantity demanded (a) (b)
Elasticity: Measure of Responsiveness • Straight-lines demand curves • Slope – same • From left to right • Elasticity – smaller • Unit-elastic demand curves • Elasticity = 1 • 10% rise in price • 10% drop in quantity demanded
Figure 3 (c), (d) Demand curves with different elasticities D D Straight-line demand curve A Unit-elastic demand curve B 4 C A’ U S T 10 D B’ 1 C’ D 3 0 0 4 7 5 2 20 U’ 7 14 $6 $30 Price Price Quantity demanded Quantity demanded (d) (c)
Table 1 Estimates of price elasticities
Total Revenue and Total Expenditure • Total revenue = PˣQ • Total expenditure = PˣQ • Effects of price decrease • Total revenue – decrease • Quantity – increase • Total revenue – increase
Total Revenue and Total Expenditure • Increase in price • Demand – elastic • Total revenue - decrease • Demand – unit elastic • Total revenue – no change • Demand – inelastic • Total revenue – increase
Figure 4 An elastic demand curve D 5 D 3 V U R T S W 2 1 4 0 $6 4 12 Quantity demanded Price
What Determines Demand Elasticity? • Nature of good • Necessities – inelastic demand • Luxury goods – elastic demand • Availability of close substitutes • Close substitutes: demand – more elastic • No close substitutes: demand – inelastic • Narrowly defined: more elastic
What Determines Demand Elasticity? • Share of consumer’s budget • Small – inelastic demand • Large – elastic demand • Passage of time • Short run – inelastic demand • Long run – elastic demand
Elasticity as a General Concept • Income elasticity of demand • Ratio of • Percentage change in quantity demanded • To: percentage change in income • Price elasticity of supply • Ratio of • Percentage change in quantity supplied • To: percentage change in price
Elasticity as a General Concept • Complements • Increase: quantity consumed of one good • Increase: quantity demanded of other good • Substitutes • Increase: quantity consumed of one good • Decrease: quantity demanded of other good
Elasticity as a General Concept • Cross elasticity of demand for X • To change in price for Y • Ratio of: • Percentage change in quantity demanded of X • To: percentage change in price of Y • Positive • Substitutes • Negative • Complements
Time Period of Demand Curve • Demand curve • During a particular time period • An optimal decision • Best serves objectives • Explicit or implicit comparison
Time Period of Demand Curve • Demand curve • Set - hypothetical quantity responses • To: set - potential prices • Firm – can charge one price • All points on demand curve • Alternative possibilities • Same time period
Application: Polaroid vs. Kodak • 1989, trial, U.S. district court • Judgment against Eastman-Kodak • Patent infringement of technology • Designed by Polaroid • 10-year period (1976-1986) • Amount of money Kodak owed Polaroid • Profit loss by Polaroid • Price elasticity of demand • Cross elasticity of demand
Application: Polaroid vs. Kodak • Price elasticity of demand • Sales – increase (instant camera) • Fall in price • Kodak’s good reputation • Rise in consumer confidence • After 1980 • Sales of instant cameras - drop sharply • Price of conventional cameras - drop
Application: Polaroid vs. Kodak • Cross elasticity of demand • Instant cameras • Conventional cameras • Elasticity calculations • Polaroid • $9 billion • Kodak • $450 million
How can we find a legitimate demand curve from historical statistics? • Estimating demand curve statistically • Collect - set of figures • Prices • Quantities sold • Different periods • Plott points • Draw a line – demand curve
Table 2 Historical data on price and quantity
Figure 5 Plot of historical data on price and quantity T $8.20 8.00 7.80 7.60 Average Price 7.40 Feb. March May Jan. S R 7.20 April T 7.00 0 90 91 92 93 94 95 97 98 96 Quantity Demanded in thousands
Demand curve from historical statistics • Problems • Different periods of time • Actual sales figures • Actual demand curve • May have shifted
Figure 6 Plot of historical data and true demand curves for January, February, and March T $8.20 8.00 F 7.80 7.60 Average Price 7.40 M M F W March Feb. J Jan. S R 7.20 T 7.00 J 0 90 91 92 93 94 95 97 98 96 Quantity Demanded in thousands
Illustration: Did the Advertising Program Work? • Historical data - Relationship • Quantity demanded always rose • As advertising rose • Too perfect • Advertising spending • Based on sales
Legitimate demand curve from historical data • Demand for umbrellas • Price changes • Movement along • Amount of rainfall changes • Shift of demand • Data • Demand curve – no change • Supply curve – shifted
Figure 7 Legitimate demand curve estimation from statistical data