Didier Laussel

Faculty ,  Aix-Marseille Université , Faculté d'économie et de gestion (FEG)

Public economics
Status
Emeritus professor
Research domain(s)
Industrial organization, International economics and economic geography, Public economics
Thesis
1974, Université de Grenoble 2
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Contact
didier.laussel[at]univ-amu.fr
+33(0)4 42 93 59 84
Address

Maison de l'économie et de la gestion d'Aix
424 chemin du viaduc, CS80429
13097 Aix-en-Provence Cedex 2

Abstract div>We study a simple model in which two vertically differentiated firms compete in prices and mass advertising on an initially uninformed market. Consumers differ in their preference for quality.There is an upper bound on prices since consumers cannot spend more on the good than a fixed amount (say, their income). Depending on this income and on the ratio between the advertising cost and quality differential (relative advertising cost), either there is no equilibrium in pure strategies or there exists one of the following three types: (1) an interior equilibrium, where both firms have positive natural markets and charge prices lower than the consumer's income; (2) a constrained interior equilibrium, where both firms have positive natural markets, and the high-quality firm charges the consumer's income or (3) a corner equilibrium, where the low-quality firm has no natural market selling only to uninformed customers. We show that no corner equilibrium exists in which the high-quality firm would have a null natural market. At an equilibrium (whenever there exists one), the high-quality firm always advertises more, charges a higher price and makes a higher profit than the low-quality one. As the relative advertising cost goes to infinity, prices become equal and the advertising intensities converge to zero as well as the profits. Finally, the advertising intensities are, at least globally, increasing with the quality differential. Finally, in all cases, as the advertising parameter cost increases unboundedly, both prices converge increasingly towards the consumer's income.
Keywords Vertical differentiation, Advertising cost, Random advertising
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Abstract We consider a nondurable good monopolist that collects data on its customers in order to profile them and subsequently practice price discrimination on returning customers. The monopolist’s price discrimination scheme is leaky in the sense that an endogenous fraction of consumers choose to incur a privacy cost to conceal their identity when they return in the following periods. We characterize the Markov perfect equilibrium of the game under two alternative customer profiling regimes: full information acquisition (FIA) and purchase history information (PHI). In both cases, we find that, contrary to what could be expected, the monopolist’s aggregate profit is not monotonically increasing in the level of the privacy cost, but a U-shaped function of it, leading to ambiguous profit effects: a reduction in privacy costs increases the fraction of customers who choose to be anonymous (detrimental profit effect), but it also softens the firm’s introductory price, reducing the pace at which prices targeted to new customers fall over time (positive profit effect). When comparing results under FIA and PHI, we find that market expansion is faster, and more customers conceal their identity under FIA than under PHI. Equilibrium profits are also higher in the FIA case. Although equilibrium profits are U-shaped functions of the privacy cost in both profiling regimes, they tend to be globally decreasing with the privacy cost under PHI and globally increasing under FIA.
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Abstract We study price personalization in a two period duopoly with horizontally differentiated products. In the second period, a firm has collected detailed information on its old customers, using it to engage in price personalization. Customers, when returning to buy, may choose to incur a cost in order to access the standard offer of their previous provider in addition to its personalized offer and the standard offer of its rival. The analysis confirms that firms’ second period profits are boosted when consumers are active in this sense (being equal to perfect price discrimination ones when initial market hares do not differ too much) but it reveals that this advantage is dissipated and possibly over-dissipated by the resulting fierce first-period competition for the market. Two-period aggregate profits are smaller with active customers provided the consumers are naive and/or the firms patient enough. Consumers’ access to both personalized and standard firms’ offers which benefit the oligopolists in mature markets may plausibly hurt them in emergent ones. The equilibrium is shown not to depend on the level of the cost as long as it is below some critical value.
Keywords Identity management, Active customers, Behavior-Base price discrimination
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Abstract Under triopoly and Cournot competition, we study an infinite horizon Markov perfect equilibrium merger game in which in each period one of the firms (“the Buyer”) selects a bid price and then the two sellers accept or reject this offer with some probability. The possibility of a “war of attrition” equilibrium in which the seller who outlasts the other is then able to sell in the following period at a greater price, is a distinct feature of the model. Delayed monopolization is all the more likely when the discount factor is small and the ratio duopoly/ triopoly profits is important. Two other equilibria are shown to be possible: an unmerged and an immediate monopolization equilibrium. Each equilibrium is shown to correspond to a different set of parameter values. The two special cases of linear and constant price elastic demand functions are fully characterized.
Keywords Markov-perfect equilibrium, Monopolization, War of attrition, Horizontal mergers
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Abstract This paper investigates duopoly competition when horizontally differentiated firms are able to make personalized product-price offers to returning customers, within a behavior-based discrimination model. In the second period, firms can profile old customers according to their preferences, selling them targeted products at personalized prices. Product-price personalization (PP) allows firms to retain all old customers, eliminating second-period customer poaching. The overall profit effects of PP are shown to be ambiguous. In the second period, PP improves the matching between customers’ preferences and firms’ offers, but firms do not make any revenues in the rival’s turf. In the Bertrand outcome, second-period profits only increase for both firms if the size of their old turfs are not too different or initial products are not too differentiated. However, the additional second-period profits may be offset by lower first-period profits. PP is likely to increase firms’ overall discounted profits when consumers’ (firms’) discount factor is low (high) and firms’ initial products are exogenous and sufficiently different. When the location of initial products is endogenous, profits are hurt because of an additional location (strategic) effect aggravating head-to-head competition in the first period. Likewise, when a fraction of active consumers conceals their identity, PP increases second-period profits at the cost of aggressive first-period price competition. Finally, we show that the room for profitable PP enlarges considerably if firms rely on PP as an effective device to sustain tacit collusive outcomes, with firms credibly threatening to respond to first-period price deviations with second-period aggressive relocations of their standard products. This paper was accepted by Matthew Shum, marketing.
Keywords Behavior-based discrimination, Price and product targeting, Consumer poaching, Consumer retention, Segmentation, Tacit collusion
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Abstract Using a Markov-perfect equilibrium model, we show that the use of customer data to practice intertemporal price discrimination will improve monopoly profit if and only if information precision is higher than a certain threshold level. This U-shaped relationship lends support to a popular view that knowledge is good only if it is sufficiently refined. When information accuracy can only be achieved through costly investment, we find that investing in profiling is profitable only if this allows to reach a high enough level of information precision. Consumers expected surplus being a hump-shaped function of information accuracy, we show that consumers have an incentive to lobby for privacy protection legislation which raises the cost of monopoly's investment in information accuracy. However, this cost should not dissuade firms to collect some information on customers' tastes, as the absence of consumers' profiling is actually detrimental to consumers.
Keywords Endogenous investment in profiling capability, Dynamic monopoly, Consumers profiling, Consumers&#039, collective action on privacy protection legislation, Big data
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Abstract A durable good monopolist faces a continuum of heterogeneous customers who make purchase decisions by comparing present and expected price-quality offers. The monopolist designs a sequence of price-quality menus to segment the market. We consider the Markov perfect equilibrium (MPE) of a game where the monopolist is unable to commit to future price-quality menus. We obtain the novel results that: (a) under certain conditions, the monopolist covers the whole market in the first period (even when a static Mussa–Rosen monopolist would not cover the whole market), because this is a strategic means to convince customers that lower prices would not be offered in future periods and that (b) this can happen only under the stage-wise Stackelberg leadership assumption (whereby consumers base their expectations on the value of the state variable at the end of the period). Conditions under which MPE necessarily involves sequentially trading are also derived.
Keywords Product quality, Durable good monopoly, Second-degree price discrimination, Coase conjecture
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Abstract We consider a general equilibrium model with vertical preferences, where workers and consumers are differentiated respectively by their sensitivity to effort and their intensity of preference for quality. We consider a public monopoly, i.e. which is owned equally by all individuals. The question is under which conditions the firm will be privatized and at which rate/price. The decisions are taken through majority vote in a plurality system. When the firm is controlled by the State, the price is determined through a vote among all the population. Otherwise, the price is the one which maximizes the profit. We prove that, when the maximum disutility of working in the firm is higher than the maximum utility of consuming its output, privatization may emerge as a possible choice of the majority, even if no hypothesis is made on the efficiency of a private management relative to a public one.
Keywords Democracy, General equilibrium, Privatization, Vertical preferences, Majority vote, Public monopoly
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Abstract This paper studies a model of vertical successive monopolies where students/workers buy qualication from an university then sell skilled labor to a monopolist who itself sells its nal product to consumers, linking this way for the rst time the education sector to the labor and output markets. The question is whether a public university should be partially or fully privatized. The partially privatized university xes the tuition fees in order to maximize a weighted sum of prots and social welfare. A larger share of the private sector means lower training costs but, at given training costs, higher margins and lower nal output levels. We prove that partial privatization of the university is optimal when public ineciency is not too severe and that the State keeps in this case a large majority of university's shares. When the ineciency parameter increases above some critical level, one switches discontinuously to full privatization. We show that these results are robust to the introduction of a feasibility constraint requiring university prots to be non-negative following privatization.
Keywords State regulation, Partial-privatized university, Vertical dierentiation, Successive monopolies, Labor Market, Education
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Abstract We study price personalization in a two period duopoly with vertically differentiated products. In the second period, a firm not only knows the purchase history of all customers, as in standard Behavior Based Price Discrimination models, but it also collects detailed information on its old customers, using it to engage in price personalization. The analysis reveals that there exists a natural market for each firm, defined as the set of customers that cannot be poached by the rival in the second period. The equilibrium is unique, except when firms are ex-ante almost identical. In equilibrium, only the firm with the largest natural market poaches customers from the rival. This firm has highest profits but not necessarily the largest market share. Aggregate profits are lower than under uniform pricing. All consumers gain, total welfare is higher herein than under uniform pricing if firms’ natural markets are sufficiently asymmetric. The low quality firm chooses the minimal quality level and a quality differential arises, though the exact choice for the high quality depends upon the cost specification.
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Abstract We show that a monopolist's profit is higher if he refrains from collecting coarse information on his customers, sticking to constant uniform pricing rather than recognizing customers' segments through their purchase history. In the Markov perfect equilibrium with coarse information collection, after each commitment period, a new introductory price is offered to attract new customers, creating a new market segment for price discrimination. Eventually, the whole market is covered. Shortening the commitment period results in lower profits. These results sharply differ from the ones obtained when the firm can uncover the exact willingness-to-pay of each previous customer.
Keywords Price-discrimination
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Abstract We present a model of market hyper-segmentation, where a monopolist acquires within a short time all information about the preferences of consumers who purchase its vertically differentiated products. The firm offers a new price/quality schedule after each commitment period. Lower consumer types may have an incentive to delay their purchases until next period to obtain a better introductory offer. The monopolist counters this incentive by offering higher informational rents. Considering the dynamic game played by the monopolist and its customers, we find that there is always a Markov perfect equilibrium (MPE) in which the firm immediately sells the good to all customers, offering the Mussa-Rosen static equilibrium schedule to first time customers (and getting full commitment profits). However, if the commitment period between two offers is long enough, there is another MPE with gradual market expansion. Contrary to the Coasian result for a durable-good monopoly, we find that in both equilibria the profit of the monopolist increases (and the aggregate consumers surplus decreases) as the interval of commitment shrinks. The model yields policy implications for regulations on collection and storage of customers information. (C) 2020 Elsevier B.V. All rights reserved.
Keywords Informational rent, Monopoly, Customer information, Markov perfect equilibrium, Coase conjecture
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Abstract This paper shows that the platforms' private information on demand may explain the empirical observation that platforms like Amazon resell high-demand products, while acting as marketplace for low-demand goods. More precisely, the paper examines the strategic interaction between a seller and a better informed platform within a signalling game. We consider that the platform may choose between two distinct business models: act as a reseller or work as a pure marketplace between the buyers and the seller. The marketplace mode, which allows to internalize the spillover between the platform's sales and the seller's direct sales is always preferred for a low-value good. The reselling mode, which allows the platform to take advantage of its private information, may be selected in the case of high-value goods provided that (i) the externalities between direct sales and platform sales are not too strong and (ii) the difference between consumers' willingness to pay for the high and the low-value goods is large enough. Under these conditions, the game displays a Least-Cost Separating Equilibrium in which the platform works as a marketplace for low-demand goods, while it acts as a reseller in the case of high-demand goods.
Keywords Demand uncertainty, Platform, Asymmetric information, Reselling, Marketplace
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Abstract The citizen candidate models of democracy assume that politicians have their own preferences that are not fully revealed at the time of elections. We study the optimal delegation problem which arises between the median voter (the writer of the constitution) and the (future) incumbent politician under the assumption that not only the state of the world but also the politician's type (preferred policy) are the policy-maker's private information. We show that it is optimal to tie the hands of the politician by imposing both a policy floor and a policy cap and delegating him/her the policy choice only in between the cap and the floor. The delegation interval is shown to be the smaller the greater is the uncertainty about the politician's type. These results are also applicable to settings outside the specific problem that our model addresses.
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Abstract We study the determination of public tuition fees through majority voting in a vertical differentiation model where agents' returns on educational investment differ and public and private universities coexist and compete in tuition fees. The private university offers higher educational quality than its competitor, incurring higher unit cost per trained student. The tuition fee for the state university is fixed by majority voting while that for the private follows from profit maximization. Then agents choose to train at the public university or the private one or to remain uneducated. The tax per head adjusts in order to balance the state budget. Because there is a private alternative, preferences for education are not single-peaked and no single-crossing condition holds. An equilibrium is shown to exist, which is one of three types: high tuition fee (the “ends” are a majority), low tuition fee (the “middle” is a majority), or mixed (votes tie). The cost structure determines which equilibrium obtains. The equilibrium tuition is either greater (majority at the ends) or smaller (majority at the middle) than the optimal one.
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Abstract We consider a general equilibrium model with vertical preferences, where workers and consumers are differentiated, respectively, by their sensitivity to effort and their intensity of preference for quality. We consider a monopoly of which the shares are owned by a fraction of the general population. The price is determined through a vote among all the shareholders. We identify necessary and sufficient conditions for (i) an absolute (relative) majority to vote for the profit maximizing price; (ii) an absolute (relative) majority to vote for a different price. We argue that the more concentrated the ownership the more likely it is that the firm charges the profit-maximizing price.
Keywords General equilibrium, Profit maximization, Vertical preferences, Majority vote
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Abstract Two duopolists first decide in which proportions to incorporate in their product two different Lancasterian characteristics and then compete in quantities or prices. In the Cournot case, minimum differentiation obtains at equilibrium whatever the degree of substituability between the characteristics. In the Bertrand one, the equilibrium depends crucially on the degree of substituability/complementarity between the two characteristics. Maximal differential obtains if and only if the characteristics are strong enough substitutes. On the contrary as characteristics become closer and closer complements one obtains in the limit a minimal differentiation result. JEL Codes: L13. Keyword: Horizontal Product Differentiation, Lancasterian Characteristics.
Keywords Duopoly, Lancasterian Characteristics, Horizontal Product Differentiation
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Abstract We analyse the optimal contract between a risk†averse manager and the initial shareholders in a two†period model where the manager's investment effort, carried out in period 1, and his or her current effort, carried out in period 2, both impact the second†period profit, so that it may be difficult to disentangle the incentives for these two types of effort. We show that stock grants play different roles according to whether the signal of investment effort is less noisy, or noisier, than that of current effort. We determine simultaneously the optimal stock grants and the optimal restrictions on sales of shares.
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Abstract We consider a general equilibrium model with vertical preferences and one or two firms, where workers and consumers are differentiated, respectively, by their sensitivity to effort and their preference for quality. The question in this paper is whether a decentralized choice through majority vote would lead to more or less competition. We compare the duopoly and the monopoly cases from the viewpoint of each individual, then we deduce the choice of the majority. We prove that, under concentrated ownership (where owners have a null density), duopoly is always preferred by the majority; while under egalitarian ownership (where firms are equally shared by all the population), the choice of the majority depends on the relative size of workers' and consumers' segments.
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Abstract This paper studies the effects of introducing centrifugal incentives in an otherwise standard Downsian model of electoral competition. First, we demonstrate that a symmetric equilibrium is guaranteed to exist when centrifugal incentives are induced by any kind of partial voter participation (such as abstention due to indifference, abstention due to alienation, etc.) and, then, we argue that: (a) this symmetric equilibrium is in pure strategies, and it is hence convergent, only when centrifugal incentives are sufficiently weak on both sides; (b) when centrifugal incentives are strong on both sides (when, for example, a lot of voters abstain when they are sufficiently indifferent between the two candidates) players use mixed strategies—the stronger the centrifugal incentives, the larger the probability weight that players assign to locations near the extremes; and (c) when centrifugal incentives are strong on one side only—say for example only on the right—the support of players’ mixed strategies contain all policies except from those that are sufficiently close to the left extreme.
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Abstract We investigate the best signalling strategy for a monopoly introducing a new product with unobservable quality when second-period sales are linked to first-period ones and the firm may tailor its distribution network to exclude some consumers. When producing a high quality product rather than a low quality one is relatively costly with respect to the increase in quality, optimal signalling is by price alone. But when the cost differential is lower, it will be optimal to set a low first-period price, not to serve all would-be consumers at this price (selective distribution) and raise the price afterwards. Paradoxically, this strategy allows a larger customer base to be reached than in the case of pure price signalling.
Keywords Decreasing cost of quality, Increasing, Price signal, Selective distribution, Quality signal
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Abstract We analyse the issue of firm-sponsored training under product market imperfections. In this setting, qualification becomes a public good for firms when their profits are increasing in the stock of skilled workers but remains a private good to students/workers. Students have to pay a tuition fee but at the same time firms sponsor education: universities sell training to both. We prove that the proportion of skilled workers is larger in more competitive economies/industries while the share of firms in the financing of training is a monotonically decreasing function of the degree of competition. An increase of the latter indeed increases the equilibrium skilled wage while reducing its sensitivity to an increase of the supply of skilled workers. The firms’ aggregate expenditures on training per worker are nevertheless a nonmonotonic function of the competitiveness of the economy.
Keywords Product market imperfections, Labour market, Firm-sponsored training, Education
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Abstract This paper investigates the expansion of the network of a monopolist firm that produces a durable good and is also involved in the corresponding aftermarket. We characterize the Markov Perfect Equilibrium of the continuous time dynamic game played by the monopolist and the forward-looking consumers, under the assumption that consumers benefit from the subsequent expansion of the network. The paper contributes to the theoretical discussion on the validity of the Coase conjecture, analyzing whether Coase's prediction that the monopolist serves the market in a “twinkling of an eye” remains valid in our setup. We conclude that the equilibrium network development may actually be gradual, contradicting Coase's conjecture. We find that a necessary condition for such a result is the existence of aftermarket network effects that accrue (at least partly) to the monopolist firm.
Keywords Network externalities, Durable good, Coase conjecture, Aftermarkets
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Abstract In this paper we characterize the equilibrium of a duopoly market which exhibits advertising spillovers. Interestingly, we prove that the relevant distinction is not between pure positive and pure negative advertising spillovers but between strong positive spillovers and weakly positive or negative spillovers. Moreover, we prove that, depending on the extent of advertising spillovers and the agency advertising cost, we may obtain at equilibrium either two active advertisers or only one advertiser that may even push its rival out of the product market. Thus advertising and the spillovers induced from it may be a source of a monopoly situation, hence an asymmetric outcome may result from an initially symmetric situation.
Keywords Quantity competition, Agency cost, Advertising spillovers
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Abstract This paper studies the dynamic price competition between two firms that sell horizontally differentiated durable goods and, subsequently, provide exclusive complementary goods and services to their customers. The paper analyzes how optimal pricing strategies are affected by the existence of network effects associated with the size of firms' consumer base. The interaction is thoroughly analyzed as a continuous time linear-quadratic differential game. We provide a necessary and sufficient condition for the existence of a unique duopoly equilibrium in affine strategies. When this condition holds, we show that optimal pricing strategies crucially depend on the nature of the network effects.
Keywords Network effects, Linear Markov Perfect Equilibrium, Differential games, Aftermarkets
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Abstract We obtain the optimal contract for the government (principal) to regulate a manager (agent) who has a taste for empire-building that is his/her private information. This taste for empire-building is modeled as a utility premium that is proportional to the difference between the contracted output and a reference output. We find that output is distorted upward when the manager's taste for running large firms is weak, downward when it is strong, and equals a reference output when it is intermediate (in this case, the participation constraint is binding). We also obtain an endogenous reference output (equal to the expected output, which depends on the reference output), and find that the response of output to cost is null in the short-run (in which the reference output is fixed), whenever the manager's type is in the intermediate range, and negative in the long-run (after the adjustment of the reference output to equal expected output). Copyright Springer-Verlag Wien 2014
Keywords Reservation utility, Régulation, Procurement, I11, H51, H42, Empire-building, D82, Adverse selection
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Abstract We analyze a two country-two good model of international trade in which citizens in each country differ by their specific factor endowments. The trade policy in each country is set by the politician who has been elected by the citizens in a previous stage. Due to a delegation effect citizens generally favor candidates who are more protectionist than they are. The one-candidate-per-country equilibria exhibit a "protectionist drift" owing to this delegation effect. In addition, we find an additional source of protectionist drift that we call the "abstention effect". Not only do candidates wish to delegate to more protectionist colleagues, but these more protectionist colleagues who can win election, prefer still more protectionist candidates than themselves. Therefore, they have an incentive to abstain, that is, not run for election. We show that because of this abstention effect there exists a range of electable citizens all of whom are more protectionist than the median voter's most preferred candidate. We extend the analysis allowing two-candidate equilibria and the possibility that there are costs and benefits of holding office.
Keywords Theory of International Free Trade Agreements, Political economy, International trade, Customs Union
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Abstract We study ownership dynamics when the manager and the large shareholder, both risk neutral, simultaneously choose effort and monitoring level respectively to serve their non-congruent interests.We show that there is a wedge between the valuation of shares by atomistic shareholders and the large shareholder's valuation. At the Markov-perfect equilibrium, the large shareholder divests her shares. If the incongruence of their interests is mild, divestment is drastic: all her shares are sold immediately. If their interests diverge sharply, the divestment is gradual in order to prevent a sharp fall in share price. In the limit the firm becomes purely managerial.
Keywords Ownership dynamics, Managerial firms
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Abstract In this paper we first introduce an approach relying on market games to examine how successive oligopolies operate between downstream and upstream markets. This approach is then compared with the traditional analysis of oligopolistic interaction in successive markets. The market outcomes resulting from the two approaches are analysed under di¤erent technological regimes, decreasing vs constant returns.
Keywords Economie quantitative
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Abstract We study the optimal regulation of a monopolist when intrinsic efficiency (intrinsic cost) and empire building tendency (marginal utility of output) are private information, but actual cost (the difference between intrinsic cost and effort level) is observable. This is a problem of multidimensional screening with complementary activities. Results are not only driven by the prior probabilities of the four possible types, but also by the relative magnitude of the uncertainty along the two dimensions of private information. If the marginal utility of output varies much more (less) across managers than the intrinsic marginal cost, there is empire building (efficiency) dominance. In that case, an inefficient empire builder produces more (less) and at lower (higher) marginal cost than an efficient money-seeker. It is only when variabilities are similar that there may be the natural ranking of activities (empire builders produce more, while efficient managers produce at a lower cost).
Keywords Régulation, Procurement, Multidimensional screening, Empire building, Adverse selection
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Abstract This paper was originally presented at the CEFI Conference on ‘Imperfect Competition and International Trade', Aix-en-Provence (France), June 18–19, 1987. We wish to thank Avinash Dixit, who gave the initial impetus to this research. We are also grateful to Alexis Jacquemin and Paul Krugman for valuable discussion and comments. We thank also the French ‘Commissariat au Plan' for financial support and the ‘Chambre Syndicale des Constructeurs Automobiles' (CSCA) for gracious assistance.
Keywords Optimal trade policy
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Abstract We investigate how asymmetric information on final demand affects strategic interaction between a downstream monopolist and a set of up-stream monopolists, who independently produce complementary inputs. We study an intrinsic private common agency game in which each supplier i independently proposes a pricing schedule contract to the assembler, specifying the supplier's payment as a function of the assembler's purchase of input i. We provide a necessary and sufficient equilibrium condition. A lot of equilibria satisfy this condition but there is a unique Pareto-undominated Nash equilibrium from the suppliers' point of view. In this equilibrium there are unavoidable efficiency losses due to excessively low sales of the good. However, suppliers may be able to limit these distortions by implicitly coordinating on an equilibrium with a rigid (positive) output in bad demand circumstances.
Keywords Complementary inputs, Asymmetric information, Private common agency games
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Abstract We study the optimal delegation problem which arises between the median voter (writer of the constitution) and the (future) incumbent politician when not only the state of the world and but also the politician’s type (preferred policy) are the policy-maker’s private information. We show that it is optimal to tie the hands of the politician by imposing him/her both a policy floor and a policy cap and delegating him/her the policy choice only in between. The delegation interval is shown to be the smaller the greater is the uncertainty about the politician’s type. These results apply outside the specific problem to which our model is applied here.
Keywords Representative democracy, Political uncertainty, Optimal delegation
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