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BSc Economics and related programmes

BSc Economics and related programmes. Economics of Competition and Regulation EC 3015 Week 3: Market definition. Overview. Why we need market definition Key ideas: substitutes constraints on pricing Hypothetical monopolist /SSNIP approach Practical methods and examples.

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BSc Economics and related programmes

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  1. BSc Economics and related programmes Economics of Competition and Regulation EC 3015 Week 3: Market definition

  2. Overview • Why we need market definition • Key ideas: • substitutes • constraints on pricing • Hypothetical monopolist /SSNIP approach • Practical methods and examples

  3. Reasons for market definition Market definition... is a preliminary stage in the assessment of competition, such as: the existing state of competition in a market, or the effect of a merger on competition.

  4. Reasons for market definition Key ideas Reasons for specifying a market definition • The market is the context in which competition is assessed, e.g.: • Significant lessening of competition (mergers) • Significant market power (ex ante regulation) • Practical: impossible to consider every possible way of specifying the market • Choice may be contentious: => must be • clear • based on evidence

  5. Reasons for market definition Key ideas Example: Vue/Ster cinema merger • OFT referred a merger between 2 cinema chains. Concern about SLCs in: • Romford/Upminster/Thurrock area • Leeds • Edinburgh • Basingstoke • Questions: • what is the product market? • how to define the geographic market?

  6. Key ideas Reasons for market definition The product market • Candidates • cinema exhibition of films/movies • films including DVD • the leisure market including restaurants

  7. Which market definition makes most sense to you for assessing competition? • Cinema exhibition of mainstream movies • Cinema and DVD movies • Leisure activities including dining out • Something else or don’t know

  8. Reasons for market definition Key ideas Key ideas • Substitution: • if two goods are good substitutes they are effectively in the same market • Constraining pricing power • if the presence of another product “B” limits the ability of “A” to raise prices above competitive levels then B is in the same market as A These ideas are obviously related

  9. Reasons for market definition Key ideas Hypothetical monopolist test Hypothetical monopolist test -a framework for considering market definition. “It is an alternative to ad hoc determination of the relevant market by arguments about product similarity.”Link X = e.g. Cinema exhibition of films (the main activities of the merging firms) Y= e.g. Films and DVD (A broader selection of activities) X Y Z= e.g. films + DVD +leisure activities (A broader still selection of activities) Z

  10. Reasons for market definition Key ideas Hypothetical monopolist test Hypothetical monopolist test (2) 1. Start with the narrowest definition (X) 2. Could a hypothetical monopolist of X raise price above the competitive level? Or does the presence of the extra products in Y (DVDs) make this impossible? X Y If yes, keep this as the definition and stop Z If so, new definition is Y. Repeat the procedure with Y and Z

  11. Reasons for market definition Key ideas Hypothetical monopolist test Hypothetical monopolist test (3) What do we mean by “raise price above the competitive level” ? A S mall but S ignificant Non-transitory I ncrease in P rice CC mergers 5% Usually 5-10% X Typically around a year Y Z Hence, a SSNIP test

  12. Reasons for market definition Key ideas Hypothetical monopolist test Practical methods Attempt Workshop Activity 3 around now

  13. Reasons for market definition Key ideas Hypothetical monopolist test Practical methods Workshop Activity 3 feedback

  14. Question 1 X Y Z

  15. What is the relevant market for case A? • X • Y • Z • Contradictory/unclear X Y Z

  16. What is the relevant market for case B? • X • Y • Z • Contradictory/unclear X Y Z

  17. What is the relevant market for case C? • X • Y • Z • Unclear/ contradictory X Y Z

  18. Case D? • X • Y • Z • contradictory/unclear

  19. What is the nearest to competitive price? • 1 • 2 • 3 • 4 • 6 • 7 • >7

  20. Elasticity? • -9.00 • -4.00 • -2.33 • -1.50 • -1.00 • -0.67 • -0.43 • -0.25 • -0.11

  21. Monopoly price? • 9 • 8 • 7 • 6 • 5 • 4 • 3 • 2

  22. Elasticity at monopoly price? • -9.00 • -4.00 • -2.33 • -1.50 • -1.00 • -0.67 • -0.43 • -0.25 • -0.11

  23. Reasons for market definition Key ideas Hypothetical monopolist test Practical methods Some practical methods • Price level comparisons • Price correlations • Demand elasticities • Critical loss analysis • Diversion ratio analysis • Price-concentration studies • Transport costs • Journey time analysis (“isochrones”)

  24. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Price level comparisons Law of one price: Homogeneous products in same market will have the same price because of arbitrage. Large price differentials (if unexplained by quality differences) tend to indicate separate markets

  25. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Price correlations Similarly, if prices move closely together (for differentiated products) • suggests in same market Issues: How closely is “closely?” Can we get a benchmark Deflate by RPI or CPI first? Some other cause of correlation? Use stationarity & other analyses to correct for possible biases? See conference paper by MnCube et.al .

  26. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Price correlations Examples mentioned in MnCube et al: 1. “Stigler and Sherwin (1985) used correlation analysis to test whether the cities of Chicago, Detroit and New Orleans are in the same market for wholesale petrol. They correlate monthly fuel prices in the three cities during the period 1980-82 inclusive. Their results indicate that the correlation coefficients are very high: the coefficient between New Orleans and Chicago is 0.792; that between New Orleans and Detroit is 0.967; and that between Chicago and Detroit is 0.77, hence the three cities are in the same market.” 2. Nestlé/Perrier (EU) (1992) 3. Rexam/AN (2001)

  27. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Demand elasticities • See examples in workshop 3 • Own elasticities: “low” elasticity => we have found relevant market. • How low is low? • Cross elasticities: High cross elasticitiy suggests we should add another product/location

  28. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Critical loss analysis • When we do not have econometricestimates, but have a knowledge ofcosts: • “Critical Loss Analysis calculates the hypothetical monopolist’s Critical Loss, meaning the magnitude of lost sales that would (just) make it unprofitable for the hypothetical monopolist to impose a SSNIP, and compares it against the so-called Actual Loss of sales that would result from the SSNIP. If the Actual Loss would be less than the Critical Loss, the SSNIP would be profitable, so PNOS would form a relevant market.” Farrell and Shapiro “Improving Critical loss analysis” link See Workshop 3 for an example

  29. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Diversion ratio analysis Response to question: If you could not buy A , what would you buy instead? B? C? It is a hot summer’s day and you fancy a Coke. But the Coke is all gone...

  30. What will you have instead? • Pepsi • Dr Pepper • Lemonade • Other soft drink • Hot drink • Beer • Other • I do not drink Coke

  31. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Diversion ratio analysis • Does not require actual behaviour (revealed preference) to be observed. • But Stated Preferences tend to be mistrusted by economists • In combination with other techniques can provide corroboration (or otherwise)

  32. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Price-concentration studies • Based on structure-conduct -performanceparadigm • Do prices depend on concentration in this candidate market? • If so, suggests it is a relevant market • Example: Staples/Office World • As always, econometric studies are contested!

  33. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Transport costs Useful for geographic definition If transport cost are low between P & Q • suggests P & Q are in same geographic market (can be checked by comparing prices and price trends)

  34. Practical methods Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Isochrones Useful for geographic definition: Used in CC inquiries: Supermarkets, SE airports, Vue/Ster merger, Stericycle (hospital waste)

  35. Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Isochrones Simplified case: max distance travelled by most consumers Store

  36. Price level comparisons Price correlations Demand elasticities Critical loss analysis Diversion ratio analysis Price-concentration studies Transport costs Isochrones Isochrones Simplified case: Overlap area max distance travelled by most consumers Store A Store B Are there enough consumers in the overlap area to constrain the pricing of the other store? If so they are in the same market

  37. Summary • Some basic theory to learn • Understand the SSNIP test • Many practical methods • Widely used because competition agencies require objective, auditable evidence • Different parties submit competing analyses • Interesting field for an applied economist • More next week, including “Cellophane fallacy”

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