Comparison Between Market Structures

A COMPARATIVE STUDY OF MARKET STRUCTURES Perfect Competition No. of Firms A large number, each being small. Monopolistic Competition A large number, each have some amount of market power. Oligopoly A small number, each being mutually interdependent. Monopoly Only one firm, possessing full control in the market. Size of Firms Small. Therefore each is a price taker. Relatively small but possessing some ability in setting price. Relatively big but bases its decision on other firms. Very large and is able to influence price or output but not both simultaneously. Nature of Product Homogeneous Differentiated Differentiated Unique Knowledge of Product Perfect knowledge of market by buyers and sellers Imperfect knowledge of market by buyers and sellers Imperfect knowledge of market by buyers and sellers Imperfect knowledge of market by buyers and sellers Barriers Free entry and exit from industry Free entry and exit from industry Barriers of entry and exit from industry Barriers of entry and exit from industry Mobility of Factors Perfect Mobility Perfect Mobility Imperfect Mobility Imperfect Mobility Extent of Price Control/Pricing Policy None by individual firms who take the market prevailing price Firms may either set price or output, constrained by its demand curve Firms may either set price or output, constrained by the actions of rival firms Firms may either set price or output, constrained by its demand curve Non-price Competition No advertising or other forms of promotion because of perfect competition †¢ Perfectly price elastic – each firm is a price taker because of all the above conditions †¢ D=P=AR=MR †¢ Price is constant at all levels of output †¢ The industry’s demand and supply determine the market price Advertising and other forms of promotion may take place Advertising and other forms of promotion may take place because of price rigidity †¢ Kinked demand curve – price rigidity exists because of all the above conditions †¢ D=AR and AR>MR †¢ The oligoplistic firm determines the market price or output, taking into account its competitor’s reaction No advertising or other forms of promotion because of the absence of competition †¢ Relatively price inelastic – firm is a price setter because of all the above conditions †¢ D=AR and AR>MR †¢ The monopolist determines the market price or output but not both simultaneously because it is constrained by the demand curve Demand Curve/Price Line/AR curve †¢ Relatively price elastic – each firm has some ability to set price because of all the above conditions †¢ D=AR and AR>MR †¢ The monopolistically competitive firm determines the market price or output but not both simultaneously because it is constrained by the demand curve 1 Perfect Competition Relationship between the demand curves of the Firm and Industry Price Price S P2 D1 D2 D0 P0 P1 AR2 AR0 AR1 Monopolistic Competition Demand Curve of the Firm $ Oligopoly Demand Curve of the Firm $ Monopoly Demand Curve of the Firm / Industry $ P2 P0 P1 MR Quantity Firm Quantity AR=DD Quantity MR AR=DD Quantity MR AR=DD Quantity Q1 Q0 Q2 Industry TR Curve †¢ TR = P x Q †¢ Because P is constant, TR curve is a linear upward-sloping from left to right Revenue Curves under Perfect Competition $ $ 60 TR †¢ TR = P x Q †¢ Because P falls when Q rises, TR curve is an inverted U-shape Revenue Curves under Monopolistic Competition $ †¢ TR = P x Q †¢ Because P falls when Q rises, TR curve is an inverted U-shape Revenue Curves under Oligopoly $ TR = P x Q †¢ Because P falls when Q rises, TR curve is an inverted U-shape Revenue Curves under Monopoly $ 10 AR=MR=DD AR=DD Quantity $ AR=DD Quantity MR Quantity 6 Quantity $ MR AR=DD Quantity $ MR TR Quantity TR Quantity TR Quantity MR Curve †¢ Identical to P and AR, that is, D=P=AR=MR †¢ Constant †¢ MR is less than AR, with the gradient of the MR curve twice as steep as the AR curve (implying that the MR cuts the quantity axis at half the length at which the AR cuts the quantity axis) †¢ Downward sloping, that is, is falling as quantity increases MR is less than AR, with the gradient of the MR curve twice as steep as the AR curve (implying that the MR cuts the quantity axis at half the length at which the AR cuts the quantity axis) †¢ Downward sloping, that is, is falling as quantity increases †¢ Presence of a broken line, implying the presence of price rigidity †¢ MR is less than AR, with the gradient of the MR curve twice as steep as the AR curve (implying that the MR cuts the quantity axis at half the length at which the AR cuts the quantity axis) †¢ Downward sloping, that is, is falling as quantity increases 2 Perfect Competition MC/AC Curves †¢ U-shaped in SR because of Law of Diminishing Returns †¢ U-shaped in LR because of internal economies and diseconomies of scale Monopolistic Competition †¢ U-shaped in SR because of Law of Diminishing Returns †¢ U-shaped in LR because of internal economies and diseconomies of scale Oligopoly †¢ U-shaped in SR because of Law of Diminishing Returns †¢ U-shaped in LR because of internal economies and diseconomies of scale Monopoly †¢ U-shaped in SR because of Law of Diminishing Returns †¢ U-shaped in LR because of internal economies and diseconomies of scale Profit-maximising Condition †¢ MR = MC where MC is rising (revenue from the last unit of output is equal to the cost of producing the last unit, therefore marginal profit is equal to zero) †¢ Since MR=P(=D=AR), when MR=MC, P=MC †¢ When individual firms no longer reshuffle output †¢ When maximum profits are attained †¢ SR equilibrium conditions are fulfilled, and †¢ No entry of new firms and no exit of existing firms †¢ MR = MC where MC is rising (revenue from the last unit of output is equal to the cost of producing the last unit, therefore marginal profit is equal to zero) †¢ Since P>MR, when MR=MC, P>MC MR = MC where MC is rising (revenue from the last unit of output is equal to the cost of producing the last unit, therefore marginal profit is equal to zero) †¢ Since P>MR, when MR=MC, P>MC †¢ MR = MC where MC is rising (revenue from the last unit of output is equal to the cost of producing the last unit, therefore marginal profit is equal to zero) †¢ Since P>MR, when MR=MC, P>MC Meaning of SR Equilibrium †¢ When individual firms no longer reshuffle output †¢ When maximum profits are attained †¢ SR equilibrium conditions are fulfilled, and †¢ No entry of new firms and no exit of existing firms When individual firms no longer reshuffle output †¢ When maximum profits are attained †¢ SR equilibrium conditions are fulfilled, and †¢ No entry of new firms and no exit of existing firms †¢ When individual firms no longer reshuffle output †¢ When maximum profits are attained †¢ SR equilibrium conditions are fulfilled, and †¢ No entry of new firms and no exit of existing firms Meaning of LR Equilibrium Profitability in SR †¢ Supernormal profits when the firm earns profits which are in excess of what is necessary to induce it to remain in the industry Supernormal Profits under Perfect Competition $ MC AC P0 Supernormal Profits †¢ Supernormal profits when the firm earns profits which are in excess of what is necessary to induce it to remain in the industry Supernormal Profits under Monopolistic Competition $ MC AC Supernormal Profits †¢ Supernormal profits when the firm earns profits which are in excess of what is necessary to induce it to remain in the industry Supernormal Profits under Oligopoly $ MC †¢ Supernormal profits when the firm earns profits which are in excess of what is necessary to induce it to remain in the industry Supernormal Profits under Monopoly $ MC AC Supernormal Profits AR=MR=DD P0 P0 AC Supernormal Profits P0 AR=DD MR Q0 Quantity Q0 Quantity Q0 MR AR=DD MR Quantity Q0 AR=DD Quantity 3 Perfect Competition †¢ Normal profits refers to that level of profits that is just sufficient to induce the firm to stay in the industry Normal Profits under Perfect Competition $ MC AC P0 AR=MR=DD Monopolistic Competition †¢ Normal profits refers to that level of profits that is just sufficient to induce the firm to stay in the industry Normal Profits under Monopolistic Competition $ MC AC P0 Oligopoly †¢ Normal profits refers to that level of profits that is just sufficient to induce the firm to stay in the industry Normal Profits under Oligopoly $ MC AC P0 Monopoly †¢ Normal profits refers to that level of profits that is just sufficient to induce the firm to stay in the industry Normal Profits under Monopoly $ MC AC P0 AR=DD MR Q0 Quantity Q0 Quantity Q0 MR AR=DD MR Quantity Q0 AR=DD Quantity †¢ Subnormal profits occur when the firm earns less profits than what is necessary to induce it to remain in the industry Subnormal Profits under Perfect Competition $ MC AC Subnormal profits occur when the firm earns less profits than what is necessary to induce it to remain in the industry Subnormal Profits under Monopolistic Competition $ AC MC Subnormal Profits †¢ Subnormal profits occur when the firm earns less profits than what is necessary to induce it to remain in the industry Subnormal Profits under Oligopoly $ MC AC Subnormal Profits †¢ Subnormal profits occur when the firm earns less profits than what is necessary to induce it to remain in the industry Subnormal Profits under Monopoly $ AC MC Subnormal Profits P0 Subnormal Profits AR=MR=DD P0 P0 P0 AR=DD MR Q0 Quantity Q0 Quantity Q0 MR AR=DD MR Quantity Q0 AR=DD Quantity Profitability in LR Necessarily makes normal profit because of free entry and exit from the industry †¢ Supernormal profits – beyond optimum capacity (Overutilisation where AC is rising) †¢ Normal profits – optimum capacity (Full utilisation where AC is at its minimum) †¢ Subnormal profits – below optimum capacity (Underutilisation where AC is falling) Necessarily makes normal profit because of free entry and exit from the industry †¢ Supernormal profits – below optimum capacity (Underutilisation where AC is falling) †¢ Normal profits – below capacity (Underutilisation where AC is falling) †¢ Subnormal profits – below optimum capacity (Underutilisation where AC is falling) Can be making either normal or supernormal profits because of the presence of entry to the industry †¢ Supernormal profits – below optimum capacity (Underutilisation where AC is falling) †¢ Normal profits – below capacity (Underutilisation where AC is falling) †¢ Subnormal profits – below optimum capacity (Underutilisation where AC is falling) Can be making either normal or supernormal profits because of the presence of entry to the industry †¢ Supernormal profits – below optimum capacity (Underutilisation where AC is falling) †¢ Normal profits – below capacity (Underutilisation where AC is falling) †¢ Subnormal profits – below optimum capacity (Underutilisation where AC is falling) Plant Utilisation in SR 4 Perfect Competition Plant Utilisation in LR Normal profits – optimum capacity (Full utilisation where AC is at its minimum) Monopolistic Competition Normal profits – below optimum capacity (Underutilisation where AC is falling) Oligopoly †¢ Normal profits – below optimum capacity (Underutilisation where AC is falling) †¢ Supernormal profits – below optimum capacity (Underutilisation where AC is falling) Monopoly †¢ Normal profits – below optimum capacity (Underutilisation where AC is falling) †¢ Supernormal profits – below optimum capacity (Underutilisation where AC is falling) Allocative Efficiency Allocative efficiency is attained where P=MC Allocative efficiency is NOT attained because P>MC Allocative efficiency is NOT attained because P>MC Allocative efficiency is NOT attained because P>MC EXCEPT when the monopolist is practising first degree (perfect) price discrimination Productive Efficiency (NEW vs OLD definition) NEW: Productive efficiency is attained where profit-maximising level of output is at the LRAC OLD: Productive efficiency is attained where profit-maximising level of output is at the minimum LRAC NEW: Productive efficiency is attained where profit-maximising level of output is at the LRAC OLD: Productive efficiency is NOT attained because profit maximising level of output is falling LRAC (underutilisation) NEW: Productive efficiency is attained where profit-maximising level of output is at the LRAC OLD: Productive efficiency is NOT attained because profit maximising level of output is falling LRAC (underutilisation) NEW: Productive efficiency is attained where profit-maximising level of output is at the LRAC OLD: Productive efficiency is NOT attained because profit maximising level of output is falling LRAC (underutilisation) Distinction between Firm and Industry †¢ Industry consists of many small firms producing an identical product. Therefore, there exists a distinction between firms and industry †¢ Firm’s demand curve is perfectly elastic because it is a price taker; industry’s demand curve is downward sloping †¢ SHORT-RUN – Price ? Average Variable Cost (Total Revenue ? Total Variable Cost) †¢ LONG-RUN – Price ? Average Total Cost (Total Revenue ? Total Cost) The portion of MC curve that is above the average variable cost †¢ Industry consists of many relatively small firms producing differentiated products. Therefore, there exists a distinction between firms and industry †¢ Firm’s demand curve and the industry’s demand curve is both downward sloping Industry consists of a few large firms producing differentiated products. Therefore, there exists a distinction between firms and industry †¢ Firm’s demand curve and the industry’s demand curve is kinked implying the presence of price rigidity †¢ Industry consists of only one firm producing a unique product. Therefore, there exists NO distinction between firms and industry †¢ Firm’s demand curve is the industry’s demand curve and it is downward sloping Shut-down condition †¢ SHORT-RUN – Price ? Average Variable Cost (Total Revenue ? Total Variable Cost) †¢ LONG-RUN – Price ? Average Total Cost (Total Revenue ? Total Cost) Cannot be determined because there is no unique price to a quantity and viceversa †¢ SHORT-RUN – Price ? Average Variable Cost (Total Revenue ? Total Variable Cost) †¢ LONG-RUN – Price ? Average Total Cost (Total Revenue ? Total Cost) Cannot be determined because of the presence of price rigidity †¢ SHORT-RUN – Price ? Average Variable Cost (Total Revenue ? Total Variable Cost) †¢ LONG-RUN – Price ? Average Total Cost (Total Revenue ? Total Cost) Cannot be determined because there is no unique price to a quantity and viceversa Supply Curve in SR 5