MIT 14.662 Graduate Labor Economics II Spring 2005 Lecture Note 4: Market Structure and Earnings Inequality (w/a Focus on Superstars) David Autor MIT and NBER February 17, 2005 1
1 Lecture Note IV: Market Structure and Earnings Inequality There are now a large number of models that consider how market structure or changes therein a ect earnings inequality, either directly, through price e ects, or indirectly through endogenous changes in technology or organizational form (which then lead to price e ects). A subset of the articles on your syllabus that address this topic is: 1. Acemoglu, Daron. Why do New Technologies Complement Skills: Directed Technical Change and Wage Inequality. Quarterly Journal of Economics, 113(4), 1998, 1055-1089. 2. Acemoglu, Daron. Patterns of Skill Premia. Review of Economic Studies, 70(2), 2003, 199 230. 3. Becker, Gary S. and Kevin M. Murphy. The Division of Labor, Coordination Costs and Knowledge. Quarterly Journal of Economics, 107(4), 1992, 1137-1160. 4. Feenstra, Robert and Gordon Hanson. Global Production Sharing and Rising Inequality: A Survey of Trade and Wages. NBER Working Paper No. 8372, 2001. 5. Terviö, Marko. 2004. Mediocrity in Talent Markets. UC Berkeley Haas School of Business working paper, December. 6. Thesmar, David, and Mathias Thoenig, 2000. Creative Destruction and Firm Organization Choice: A New Look into the Growth-Inequality Relationship. Quarterly Journal of Economics, 115, 1201 1238. 7. Thoenig, Mathias and Thierry Verdier. A Theory of Defensive Skill-Biased Innovation and Globalization. American Economic Review. 93(3), 2003, 709 728. 8. Rosen, Sherwin. 1981. The Economics of Superstars. American Economic Review, 71(5), 1981, 845-858. 9. Wood, Adrian. 1998. Globalization and the Rise of Labour Market Inequalities. Economic Journal, 108, September. I may mention many of these articles in class but will not spend time developing most of them, which would be a semester in itself. Two articles I will discuss brie y are the superstars articles: Rosen (1981) and Terviö (2004). 1
1.1 Rosen: The Economics of Superstars The 1981 AER article by Sherwin Rosen, The Economics of Superstars, is often cited as a prescient explanation for the rise in returns to skills that was to occur in the years immediately following its publication. In reality, the Superstars hypothesis probably may have explain little of the phenomenon of rising inequality. Nevertheless, the paper o ers a fascinating insight that has considerable currency as an explanation for why wages of CEOs, entertainers and athletes are incomparably higher than for other occupations. The idea of this paper is simple to convey; the model would take considerable time to unpack. We will simply convey the idea. Certain services appear to be characterized by a demand structure that places considerable weight on quality versus quantity. For example, a patient would rather have one really good heart operation than two mediocre ones; an opera fan would rather see one Pavoratti concert than ten mediocre operatic performances; no amount of Applebee s food amounts to a single meal at Oleana. Hence, if there is widespread agreement on who is talented among the providers of such services, one can imagine that talented service providers could earn considerable rents. There is also a natural check on the possibility that one talent will control an entire market: congestion. A single heart surgeon cannot perform all of the surgeries; Pavoratti s live audience can only get so large before the enjoyment of attending a live concert is utterly lost; a great cook can only make so many dinners in an evening. It may be these congestion externalities that prevent single talents from controlling entire markets. Now, imagine a technological improvement that reduces congestion, allowing holders of talent to more e ciently serve larger markets. Examples: television, recording technology, the web, etc. These types of technological advances may increase the rents accruing to the most talented individuals by increasing their market share (possibly to a global scale). Some professions in which this is likely to be important: all performing artists and entertainers; managers of large corporations (CEOs); athletes; possibly some academics. Is is actually hard to make a very long list. The Rosen model almost surely helps to explain why athletes and movie-stars earn such enormous salaries, and why these salaries have risen as mass communications and entertainment have improved. Hence, this model is widely accepted among economists as a leading hypothesis for why entertainers, athletes, CEOs and many other professional celebrities earn such outsized 2
salaries. It may be in part because of the widespread (universal?) acceptance of the Rosen model that economists have been reluctant to view the run-up in CEO pay and other examples of hypercompensation as evidence of market failure. 1.2 Terviö: Mediocrity in Talent Markets A paper by Marko Terviö proposes an alternative model that casts the same facts in quite a di erent light. The point of departure between the Rosen and Terviö articles is in the mechanism by which talent is discovered. Rosen takes it as given that talent is known to the market. Given full information, the wages paid to talent are likely to be e cient. Terviö s paper takes a step back by asking: how does talent become known? Terviö observes that to be discovered, one must rst audition. This observation seems plausible for many talent-occupations. In the Terviö model, knowledge about worker quality is a joint output of production. (That is, to nd out if a worker would make a good actor, he needs to appear in a movie.) Economist Richard Caves refers to this ex ante uncertainty about talent as the Nobody Knows property one cannot evaluate talent without putting it to use. Now, add a second key assumption: there are positive production costs. That is, workers cannot audition for free because some other scarce is used for the audition. This resource could be capital or, more realistically, it could be the time of skilled evaluators (talent agents, moviegoers, academics, passengers on an airplane, etc.). More generally, consumers cannot become informed about the entire array of talents potentially available in the market because time and attention devoted to discovery is scarce. To evaluate and disseminate information about talent is costly. If these assumptions are correct, there is a positive opportunity cost to auditioning a worker s talent by using him for production. The cost is that someone else better could ll the slot (therefore making better use of the same scarce resource). Now assume: 1) learning is symmetric (i.e,. my talent is revealed to the public as the same time as it is revealed to the employer this assumption can be weakened); 2) workers cannot commit to binding wage contracts (i.e., no indentured servitude); 3) workers are capital constrained so that they cannot simply buy a job to audition their talents. What does this structure imply about the operation of the market for talent? The answer is suprisingly pernicious. Rather than develop the model which Terviö does rather elegantly I will work through the example in the paper. 3
1.2.1 Terviö Example Consider a competitive industry that combines workers with capital. worker and one unit of capital at cost $4 million to produce output. Firms need one There is free entry by rms. There is an unlimited supply of potential workers, all of whom have opportunity cost $0. Hence, talent is not scarce. Output (more naturally quality rather than quantity ) entirely depends on the talent of the worker. The talent distribution is uniform on 0 to 100. T U [0; 100]. Talent is ex ante unknown to workers and becomes public after 1 period of work. Careers are nite and last at most 16 periods. The industry output faces a downward-sloping demand curve, and rms take the market price as given. Workers are constrained to take a non-negative wage (no borrowing). For simplicity, there is no discounting. Equilibrium with constrained workers like? Initial results: What does the equilibirum of this model look All workers who turn out to be above the population mean of 50 will stay in the industry until they retire. Why? These veterans create more revenue than a novice in expectation, so they can always out-compete them for a job in the industry. The market price of output must be such that novice-hiring rms break even. novices are not scarce, they will always be paid zero (their opportunity cost). Since A potential novice is expected to make 50 units, so an output price of $80; 000 is needed to recover the $4 million capital cost. At this price, there is no entry or exit. 4
The average output of veterans will be 75 (since veterans are retained if their talent exceeds the mean). The average output in the industry will be lower, since this output includes 1st period novices. In fact, the average output is 72: Why is this so? In equilibrium, out ows and in ows must be equal. Since one cohort of veterans retires each period, there must be su cient novices to replace them given quality threshold. Hence, 1= novices must be hired each period. The overall fraction of novices in the industry in each period will be: (1=((1 )) (1= (1 ) + 15) = 1 1 + 15 (1 ) : With = 0:5, the fraction of industry novices is 0:118 and average talent is 72: A novice has a fty- fty chance of being retained in the industry, in which case his expected wage for the next fteen periods is 15[(75 80; 000) 4; 000; 000] = $30 million. Hence, the lifetime rent associated with being hired into the industry is one-half of this amount, $15 million (since there is a 50 percent chance of exiting after one period). E cient benchmark Now we want to ask: what should happen? Suppose that workers are risk neutral and are not credit constrained. They will be willing to bid to enter the industry up to the value of expected future talent rents. Start by assuming that novices o er $1:5 million to rms for the chance to work (this will turn out to be the equilibrium). Then, at output price $P; a novice-hiring rm will in expectation generate 50 $P in revenue, and have a net cost of $2:5 million (since the worker has already paid $1:5 million for the job and the capital cost is $4 million). For rms to break even, the equilibrium price of output must therefore be $50K ($50K50 = $2:5 million). At this price, it is only worthwhile for a novice to stay in the industry (that is, become a veteran) if his talent is greater than or equal to 80 (since $80K50 = $4 million). The expected talent of veterans is therefore 90. 5
The average per period wage of veterans is $90K50 $4; 000K= $0:5 million. So, the expected lifetime rent of novices entering the industry is :215:5 million = $1:5 million, which is the price of buying a job we had assumed initially. Each period, this many new novices must be hired (as a fraction of all employed): 1= (1 + 15 (1 :8)) = :25 The average output in the industry, including novices will be: :25 50 + :75 90 = 80 Comparison Let s compare the characteristics of this equilibrium to the previous one: Original Benchmark Output price $80K $50K Threshold talent 50 80 Average talent 72 80 Top wage $4 million $1 million Proportion novices 12% 25% What is quite striking here is that the original equilibrium has lower talent and higher wages than the e cient benchmark. Why? Because the orginal equilibrium has arti cial talent scarcity. Because talent rents accrue to workers not rms, rms have insu cient incentive to create new opportunities for talent revelation (in fact, they have none). So, there is underexperimentation, excess retention of mediocre talent, and ine ciently high rents. This problem could be solved in either of two ways: (1) the legalization of binding indentured servitude contracts such that a worker s wage is set independent of output and the worker cannot quit once hired (but can be red in the 1st period) this used to happen in European Soccer through the transfer fees system; (2) the removal of credit constraints so that workers can bid for jobs. This bidding will generate an e cient market in talent revelation. You might yourself whether the markets for CEOs, athletes, movie stars and other celebrity professionals appears to satisfy (1) or (2). The paper is well worth reading for its formal development of these ideas. The extension of the model to has beens is particularly surprising and elegant. An interesting point on which 6
to speculate is whether this model is, in some sense, more general the Rosen model; that is, whether it could nest the Rosen model as a special case where talent revelation is costless. To sum up, the key insight suggested by this model is that talent can receive large rents even if that talent is mediocre. The reason is that the (ex-post) realization of the known talent distribution may have arti cial scarcity. It will be interesting to observe whether this paper has an impact on the economic presumption that the market for superstars is in some intrinsic sense e cient. 7
Source: Tervio 2004