Managerial Economics & Business Strategy Chapter 8 Managing in Competitive, Monopolistic, and Monopolistically Competitive Markets Overview I. Perfectly Competition II. Monopolies III. Monopolistic Competition Perfect Competition • • • • • Many buyers and sellers Homogeneous product Perfect information No transaction costs (mobility) Free entry and exit PRICE-TAKERS Key Implications • Firms are “price takers” (price determined by interaction of buyers and sellers) n P = MR • In the short-run, firms may earn profits or losses • Long-run economic profits are zero (accounting profits 0) Unrealistic? Why Learn? • Many small businesses are “price-takers,” and decision rules for such firms are similar to those of perfectly competitive firms • It is a useful benchmark • Explains why governments oppose monopolies • Illuminates the “danger” to managers of competitive environments n n Importance of product differentiation Sustainable advantage Setting Price $ $ S Pe MR=Df D QM Market Firm Qf $ Setting Output: C(Q) C(Q), R R=PQ Slope of revenue curve is MR (linear, so constant) Slope of tangent line to C(Q) is MC (nonlinear so MC constantly changing). AT Q0 , MC=MR. Q1 Q0 Q2 Output (Q) Setting Output: • MR = MC where • MR = P, therefore • To max , choose Q when P = MC dR MR dQ dC MC dQ Graphically (recall cost curves from Chapter 5) Profit = (Pe - ATC) Qf* MC $ ATC AVC Pe = Df = MR Pe ATC Qf* Qf • Given n A Numerical Example P=$80 and C(Q) = 40 + 8Q + 2Q2 • (Q) = PQ – C(Q) n (Q) = 80Q – [40 + 8Q + 2Q2] • Optimal Q: set MR = MC and solve for Q; or find d /dQ, set equal to zero and solve for Q. n n n MR = P = $80 and MC = 8 + 4Q d /dQ = 80 – 8 – 4Q = 0. Solving for Q in either case, Q = 18 units. • Max Profits? To ensure maximum, find 2nd derivative of function. If 2nd derivative is negative (concave down), then indeed a maximum. n n d2 /dQ2 = - 4, therefore concave down. PQ - C(Q) = (80)(18) – [40 + 8(18) + 2(182)] = $608 Long Run Adjustments? • If firms are price takers but there are barriers to entry, profits will persist • If the industry is perfectly competitive, firms are not only price takers but there is free entry n Other “greedy capitalists” enter the market Effect of Entry on Price? $ $ S Entry S* Pe Pe* Df Df* D QM Market Firm Qf Effect of Entry on the Firm’s Output and Profits? MC $ AC Pe Df Pe* Df* QL Qf* Q Summary of Logic • Short run profits leads to entry • Entry increases market supply, drives down the market price, increases the market quantity • Demand for individual firm’s product shifts down • Firm reduces output to maximize profit • Long run profits are zero Negative Profits in the SR (AVC<P<ATC): Negative economic profits, but less than paying FC $ ATC Pe AVC MC ATC AVC Df = MR FC Revenues VC Qf Quantity Summary: Negative Economic Profits • In SR, if AVC<P<ATC, OPERATE to cover portion of FC (look at 8-5) • In LR, EXIT. As firms exit, supply falls and price rises. • In SR, if P=AVC, DON’T OPERATE and pay FC. This is referred to as the n SHUTDOWN RULE • Supply curve is MC above minimum of AVC. Negative Profits in the SR (P = minimum of AVC) MC $ ATC Supply AVC Df = MR Pe=AVC Qf Quantity Features of Long Run Competitive Equilibrium • P = MC n Socially efficient output • P = minimum ATC n Zero profits • Firms are earning just enough to offset their opportunity cost Monopoly • Single firm serves the “relevant market” n Most monopolies are “local” monopolies (can exist even if size of firm small) • The demand for the firm’s product is the market demand curve • Firm has control over price n But the price charged affects the quantity demanded of the monopolist’s product (don’t have unlimited Psetting power) Sources of Monopoly Power • • • • • • Economies of scale Patents and other legal barriers (licenses) Exclusive Contracts Collusion Ownership or control of a scarce resource Government restrictions (e.g., Utah State Liquor Stores) • Product Proliferation (Microsoft) A Monopolist’s Marginal Revenue P Elastic Unitary Inelastic Demand Q Total Revenue ($) MR Q Monopoly Profit Maximization Produce where MR = MC. Charge the price on the demand curve that corresponds to that quantity. MC $ ATC Profit PM ATC D QM MR Q Useful Formulas • What’s the MR if a firm faces a linear demand curve for its product? • P(Q) = a + bQ (inverse D function & b<0) • MR = a + 2bQ Math Note: R(Q) = P(Q)Q = (a + bQ)Q = aQ + bQ2 MR = R(Q) = a + 2bQ! With a little algebra, we could show that MR = P[(1+E)/E], E is elasticity of D Useful Formulas Math Note: MR = P[(1+E)/E] Because MR=MC at profit-maximizing output then MC = P[(1+E)/E] Rearranging terms: (P-MC)/P = -1/E (i.e., the Lerner Index) Example Using, MR = P[(1+E)/E] {Note: Don’t take |E| when solving.} Price = $1.25, MC = $0.25, and E = -2.5. Based on this information, what should the firm do to boost profits? A Numerical Example • Given estimates of • P = 10 - Q • C(Q) = 6 + 2Q • Optimal output? Set MR = MC or find derivative of profit function and set equal to zero. • • • • MR = 10 - 2Q MC = 2 10 - 2Q = 2 Q = 4 units • Optimal price? Plug Q into inverse demand function • P = 10 - (4) = $6 • Maximum profits? • PQ - C(Q) = (6)(4) - (6 + 8) = $10 Long Run Adjustments? • None, unless the source of monopoly power is eliminated. Why Government Dislikes Monopoly? • P > MC n Too little output, at too high a price • Deadweight loss of monopoly Deadweight Loss of Monopoly $ MC Deadweight Loss of Monopoly ATC Recall: D represents WTP, thus it is a MB D curve. PM MR=MC QM MR Q Arguments for Monopoly • The beneficial effects of economies of scale or economies of scope on price and output may outweigh the negative effects of market power • Encourages innovation Monopolistic Competition • Numerous buyers and sellers • Differentiated products n Implication: Since products are differentiated, each firm faces a downward sloping demand curve. • Firms have limited market power. • Free entry and exit n Implication: Firms will earn zero profits in the long run. Managing a Monopolistically Competitive Firm • Market power permits you to price above marginal cost, just like a monopolist. • How much you sell depends on the price you set, just like a monopolist. But … • The presence of other brands in the market makes the demand for your brand more elastic than if you were a monopolist. • You have limited market power. Marginal Revenue Like a Monopolist P Elastic Unitary Inelastic Total Revenue ($) Demand Q MR Q Monopolistic Competition: Profit Maximization • Maximize profits like a monopolist n Produce where MR = MC • Charge the price on the demand curve that corresponds to that quantity Graphically MC $ ATC Profit PM ATC D QM MR Quantity of Brand X Long Run Adjustments? • In the absence of free entry, no adjustments occur. • If the industry is truly monopolistically competitive, there is free entry. n n In this case other “greedy capitalists” enter, and their new brands steal market share. This reduces the demand for your product until profits are ultimately zero. Graphically Long Run Equilibrium (P = AC, so zero profits) $ MC AC P* P1 Entry MR Q1 Q* MR1 D D1 Quantity of Brand X Monopolistic Competition The Good (To Consumers) n Product Variety The Bad (To Society) n n P > MC (MB>MC) Excess capacity • Unexploited economies of scale because P>min AC. The Ugly (To Managers) n Zero Profits Strategies to Avoid (or Delay) the Zero Profit Outcome • Comparative Advertisements • Be the first to introduce new brands or to improve existing products and services, “New Improved…” • Seek out sustainable niches. • Create barriers to entry. • Guard “trade secrets” and “strategic plans” to increase the time it takes other firms to clone your brand. Maximizing Profits: A Synthesizing Example • C(Q) = 125 + 4Q2 • Determine the profit-maximizing output and price, and discuss its implications, if n n n You are a price taker and other firms charge $40 per unit; You are a monopolist and the inverse demand for your product is P = 100 - Q; You are a monopolistically competitive firm and the inverse demand for your brand is P = 100 – Q. Marginal Cost • C(Q) = 125 + 4Q2, • So MC = 8Q • This is independent of market structure Price Taker • MR = P = $40 • Set MR = MC • 40 = 8Q • Q = 5 units • Cost of producing 5 units • C(Q) = 125 + 4Q2 = 125 + 100 = 225 • Revenues: • PQ = (40)(5) = 200 • Maximum profits of -$25 • Implications: Expect exit in the long-run Monopoly/Monopolistic Competition • MR = 100 - 2Q (since P = 100 - Q) • Set MR = MC, or 100 - 2Q = 8Q n n n Optimal output: Q = 10 Optimal price: P = 100 - (10) = 90 Maximum profits: • PQ - C(Q) = (90)(10) -(125 + 4(100)) = 375 • Implications n n Monopolist will not face entry (unless patent or other entry barriers are eliminated) Monopolistically competitive firm should expect other firms to clone, so profits will decline over time