
on Microeconomics 
By:  Harry Pei 
Abstract:  I study a reputation model in which a patient player privately observes a persistent state that affects his myopic opponents' payoffs, and can be one of the several commitment types that plays the same (possibly mixed) action over time. The main result is a characterization of the set of environments under which the patient player obtains at least his commitment payoff in all equilibria regardless of his stagegame payoff function. My result implies that small perturbations to a pure commitment action can lead to a discontinuous change in the patient player's equilibrium payoff. The main technical contribution is to use martingale techniques to construct a nonstationary strategy under which the patient player can avoid signaling negative information about the state while at the same time, matching the longrun frequency of his actions to the mixed commitment action and convincing his opponents that his action is close to the commitment action in almost all periods. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.16206&r=all 
By:  Sakamoto, Norihito 
Abstract:  This paper characterizes new efficient and equitable social welfare orderings when individual wellbeings are fully interpersonal comparable. Previous studies show that social welfare orderings satisfying the axioms of strong Pareto, anonymity, separability, and minimal equity are either weak utilitarian or leximin rules. By dropping the separability axiom, this study shows that there are various classes of distributionsensitive social welfare orderings. In fact, simply imposing rankseparability instead of separability enables a class of social welfare orderings satisfying the axioms of strong Pareto, anonymity, and PigouDalton transfer equity to be a generalized leximin rule (a general distributionsensitive rule including leximin, rankdependent utilitarianism, and their lexicographic compositions). This result is proved by a simple method that is intuitive and easy to understand without the need for advanced mathematical techniques, such as functional analysis and the hyperplane separation theorem, which are often used in typical social choice analyses. Following this new proof, the mechanism by which a class of reasonable social welfare orderings satisfying separability is limited to weak utilitarian and leximin rules can be easily understood and proved. This study also shows the impossibility theorem between the axioms of equity and continuity. Based on the results of previous studies and this paper, theoretical relationships between interpersonal comparability of individual wellbeing and equality axioms are clarified. That is, if the interpersonal comparability of wellbeing is a cardinal unit or ratio one, then Paretian and anonymous social welfare orderings are limited to KolmPollack or Atkinson social welfare functions. If it is the ordinal level comparability, the desirable rule must be leximin. If it is the cardinal full comparability, the generalized leximin should be used. 
Keywords:  Social Welfare Ordering, Joint Characterization, Generalized Leximin 
JEL:  D71 D81 
Date:  2020–04 
URL:  http://d.repec.org/n?u=RePEc:hit:rcnedp:7&r=all 
By:  MoragaGonzález, JoséLuis; Sándor, Zsolt; Wildenbeest, Matthijs 
Abstract:  This paper extends the literature on simultaneous search by allowing for differentiated products and consumer search cost heterogeneity. In a duopolistic market, consumers with sufficiently low search costs choose to inspect the products of the two firms and purchase, if any, the most suitable; consumers with higher search costs choose to examine just one of the products; consumers with prohibitively high search costs do not check any of the products and drop out of the market altogether. For arbitrary search cost distributions, when match values are assumed to be uniformly distributed, a symmetric price equilibrium always exists. We provide a necessary and sufficient condition on the search cost distribution under which an increase in the costs of search of all consumers may result in a lower, equal or higher equilibrium price. The effects of prominence on equilibrium prices are also studied. The prominent firm charges a higher price than the nonprominent firm and both their prices are below the symmetric equilibrium price. Consequently, with simultaneous search, market prominence increases the surplus of consumers. In an extension, we provide conditions under which the equilibrium of the Nfirm model exists. 
Keywords:  differentiated products; nonsequential search; nonuniform sampling; oligopoly; Prominence; Search cost heterogeneity; simultaneous search 
JEL:  C72 D43 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14454&r=all 
By:  Igor Letina; Shuo Liu; Nick Netzer 
Abstract:  We consider the design of contests for n agents when the principal can choose both the prize profile and the contest success function. Our framework includes Tullock contests, LazearRosen tournaments and allpay contests as special cases, among others. We show that the optimal contest has an intermediate degree of competitiveness in the contest success function, and a minimally competitive prize profile with n1 identical prizes. The optimum can be achieved with a nested Tullock contest. We extend the model to allow for imperfect performance measurement and for heterogeneous agents. We relate our results to a recent literature which has asked similar questions but has typically focused on the design of either the prize profile or the contest success function. 
Keywords:  contest design, optimal contests, tournaments 
JEL:  D02 D82 M52 
Date:  2020–05 
URL:  http://d.repec.org/n?u=RePEc:ube:dpvwib:dp2011&r=all 
By:  Anton Kolotilin (School of Economics, UNSW Business School); Hongyi (School of Economics, UNSW Business School) 
Abstract:  We study a communication game between an informed sender and an uninformed receiver with repeated interactions and voluntary transfers. Transfers motivate the receiver’s decisionmaking and signal the sender’s information. Although full separation can always be supported in equilibrium, partial or complete pooling is optimal if the receiver’s decisionmaking is highly responsive to information. In this case, the receiver’s decisionmaking is disciplined by pooling extreme states, where she is most tempted to defect. 
Keywords:  strategic communication, relational contracts 
JEL:  C73 D82 D83 
Date:  2020–07 
URL:  http://d.repec.org/n?u=RePEc:swe:wpaper:201812b&r=all 
By:  Reshef Meir; Fedor Sandomirskiy; Moshe Tennenholtz 
Abstract:  A population of voters must elect representatives among themselves to decide on a sequence of possibly unforeseen binary issues. Voters care only about the final decision, not the elected representatives. The disutility of a voter is proportional to the fraction of issues, where his preferences disagree with the decision. While an issuebyissue vote by all voters would maximize social welfare, we are interested in how well the preferences of the population can be approximated by a small committee. We show that a ksortition (a random committee of k voters with the majority vote within the committee) leads to an outcome within the factor 1+O(1/k) of the optimal social cost for any number of voters n, any number of issues $m$, and any preference profile. For a small number of issues m, the social cost can be made even closer to optimal by delegation procedures that weigh committee members according to their number of followers. However, for large m, we demonstrate that the ksortition is the worstcase optimal rule within a broad family of committeebased rules that take into account metric information about the preference profile of the whole population. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.07837&r=all 
By:  Yuval Heller; Erik Mohlin 
Abstract:  We study environments in which agents are randomly matched to play a Prisoner's Dilemma, and each player observes a few of the partner's past actions against previous opponents. We depart from the existing related literature by allowing a small fraction of the population to be commitment types. The presence of committed agents destabilizes previously proposed mechanisms for sustaining cooperation. We present a novel intuitive combination of strategies that sustains cooperation in various environments. Moreover, we show that under an additional assumption of stationarity, this combination of strategies is essentially the unique mechanism to support full cooperation, and it is robust to various perturbations. Finally, we extend the results to a setup in which agents also observe actions played by past opponents against the current partner, and we characterize which observation structure is optimal for sustaining cooperation. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.15310&r=all 
By:  Amelio, Andrea; Karlinger, Liliane; Valletti, Tommaso 
Abstract:  This paper studies the incentives to engage in exclusionary pricing in the context of twosided markets. Platforms are horizontally differentiated, and seek to attract users of two groups who singlehome and enjoy indirect network externalities from the size of the opposite user group active on the same platform. The entrant incurs a fixed cost of entry, and the incumbent can commit to its prices before the entry decision is taken. The incumbent has thus the option to either accommodate entry, or to exclude entry and enjoy monopolistic profits, albeit under the constraint that its price must be low enough to not leave any room for an entrant to cover its fixed cost of entry. We find that, in the spirit of the literature on limit pricing, under certain circumstances even platforms find it profitable to exclude entrants if the fixed entry cost lies above a certain threshold. By studying the properties of the threshold, we show that the stronger the network externality, the lower the thresholds for which incumbent platforms find it profitable to exclude. We also find that entry deterrence is more likely to harm consumers the weaker are network externalities, and the more differentiated are the two platforms. 
Keywords:  Exclusionary practices; externalities; limit pricing; platforms; twosided markets 
JEL:  D40 L13 L41 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14406&r=all 
By:  Deb, Rahul; Mitchell, Matthew; Pai, Mallesh 
Abstract:  Motivated by markets for "expertise," we study a bandit model where a principal chooses between a safe and risky arm. A strategic agent controls the risky arm and privately knows whether its type is high or low. Irrespective of type, the agent wants to maximize duration of experimentation with the risky arm. However, only the high type arm can generate value for the principal. Our main insight is that reputational incentives can be exceedingly strong unless both players coordinate on maximally inefficient strategies on path. We discuss implications for online content markets, term limits for politicians and experts in organizations. 
Keywords:  bad reputation; experts; relational contracting 
JEL:  C73 D82 D86 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14408&r=all 
By:  IngHaw Cheng (Dartmouth College); Alice Hsiaw (Brandeis University) 
Abstract:  What deters individuals from reporting sexual misconduct, and what are the effects of #MeToo for reporting? We show that individuals underreport sexual misconduct if and only if a manager's misconduct is widespread. The reason is that individuals face a coordination problem and strategic uncertainty over whether others will also report misconduct. The coordination problem occurs because reports from multiple individuals corroborate a pattern of behavior and mitigate the chances of retaliation. We then study three unintended and intended consequences of #MeToo. First, managers may avoid mentoring individuals due to possible reporting. This selection effect spills over into individuals' willingness to report and can reduce the effectiveness of policies intended to encourage reporting. Second, heightened public awareness of misconduct encourages individuals to report otherwisehidden misconduct by coordinating beliefs. Finally, whistleblower rewards mitigate this coordination problem when appropriately calibrated. 
Keywords:  Misconduct, Reporting, Retaliation, Coordination 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:brd:wpaper:129&r=all 
By:  Daniel Cardona (Universitat de les Illes Balears); Jenny De Freitas (Universitat de les Illes Balears); Antoni RubíBarceló (Universitat de les Illes Balears) 
Abstract:  Lottery and share contests are equivalent for risk neutral contestants. We compare these two contests designs to show that this equivalence does no longer hold for risk averse contestants, in a policy contest setting. As expected, they prefer the share contest as it eliminates the uncertainty of the lottery. Under institutional settings in which contestants can precommit to policies different from their ideal one, the previous result is switched: Riskaverse contestants prefer lottery contests because, only under this design, they strategically moderate their claims, calming down the conflict and reducing the uncertainty of the lottery. Moreover, we show that contestants exert more effort in share contests. These results provide arguments justifying each of these two types of contests depending on the institutional framework and the comparative criteria. 
Keywords:  lobbying; lottery contest; share contest; risk aversion; commitment; strategic restraint. 
JEL:  C72 D72 D81 H40 
Date:  2020 
URL:  http://d.repec.org/n?u=RePEc:ubi:deawps:93&r=all 
By:  Ernesto Savaglio; Stefano Vannucci 
Abstract:  Three characterizations of the whole class of strategyproof aggregation rules on rich domains of locally unimodal total preorders in Önite median joinsemilattices are provided. In particular, it is shown that such class consists precisely of generalized weak consensussponsorship rules induced by certain families of order Ölters of the coalition poset. It follows that the comajority rule and many other inclusive aggregation rules belong to that class. The comajority rule for an odd number of agents is also characterized. The existence of strategyproof anonymous neutral and unanimityrespecting social welfare functions which satisfy a suitably relaxed independence condition is shown to follow from our characterizations. 
JEL:  D71 
Date:  2020–07 
URL:  http://d.repec.org/n?u=RePEc:usi:wpaper:834&r=all 
By:  Jiangtao Li (National University of Singapore); Piotr Dworczak (Group for Research in Applied Economics (GRAPE); Northwestern University) 
Abstract:  We study the design of mechanisms involving agents that have limited strategic sophistication. The literature has identified several notions of simple mechanisms in which agents can determine their optimal strategy even if they lack cognitive skills such as predicting other agents' strategies (strategyproof mechanisms), contingent reasoning (obviously strategyproof mechanisms), or foresight (strongly obviously strategyproof mechanisms). We examine whether it is optimal for the mechanism designer who faces strategically unsophisticated agents to offer a mechanism from the corresponding class of simple mechanisms. We show that when the designer uses a mechanism that is not simple, while she loses the ability to predict play, she may nevertheless be better off no matter how agents resolve their strategic confusion. 
Keywords:  Simple mechanisms, complex mechanisms, robust mechanism design, dominantstrategy mechanisms, obviously strategyproof mechanisms, strongly obviously strategyproof mechanisms 
JEL:  D71 D82 D86 
Date:  2020 
URL:  http://d.repec.org/n?u=RePEc:fme:wpaper:42&r=all 
By:  Sela, Aner 
Abstract:  We study bestofthree allpay auctions with two players who compete in three stages with a single match per stage. The first player to win two matches wins the contest. We assume that a prize sum is given, and show that if players are symmetric, the allocation of prizes does not have any effect on the players' expected total effort. On the other hand, if players are asymmetric, in order to maximize the players' expected total effort, independent of the players' types, it is not optimal to allocate a single final prize to the winner. Instead, it is optimal to allocate intermediate prizes in the first stage or/and in the second stage in addition to the final prize. When the asymmetry of the players' types is sufficiently high, it is optimal to allocate intermediate prizes in both two first stages and a final prize to the winner. 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14410&r=all 
By:  Chichilnisky, Graciela (Columbia University); Hammond, Peter J. (University of Warwick); Stern, Nicholas (LSE) 
Abstract:  Ramsey famously condemned discounting “future enjoyments” as “ethically indefensible”. Suppes enunciated an equity criterion which, when social choice is utilitarian, implies giving equal weight to all individuals’ utilities. By contrast, Arrow (1999a, b) accepted, perhaps reluctantly, what he called Koopmans’ (1960) “strong argument” implying that no equitable preference ordering exists for a suﬃciently unrestricted domain of inﬁnite utility streams. Here we derive an equitable utilitarian objective for a ﬁnite population based on a version of the Vickrey–Harsanyi original position, where there is an equal probability of becoming each person. For a potentially inﬁnite population facing an exogenous stochastic process of extinction, an equitable extinction biased original position requires equal conditional probabilities, given that the individual’s generation survives the extinction process. Such a position is welldeﬁned if and only if survival probabilities decline fast enough for the expected total number of individuals who can ever live to be ﬁnite. Then, provided that each individual’s utility is bounded both above and below, maximizing expected “extinction discounted” total utility — as advocated, inter alia, by the Stern Review on climate change — provides a coherent and dynamically consistent equitable objective, even when the population size of each generation can be chosen 
Keywords:  Discounting ; time perspective ; fundamental preferences ; fundamental utilitarianism ; consequentialization ; Vickrey–Harsanyi original position ; Suppes equity ; intergenerational equity ; sustainable preferences ; extinction discounting. Jel Classification: D63 ; D70 ; D90 ; Q54 ; Q56 
Date:  2019 
URL:  http://d.repec.org/n?u=RePEc:wrk:wcreta:55&r=all 
By:  Sela, Aner 
Abstract:  We study two reverse contests, A and B, with two agents, each of whom has both a linear reward function that increases in the agent's effort and an effort constraint. However, since the effort (output) of the agents has a negative effect on society, if the agents' effort constraints are relatively high, the designer in reverse contest A imposes a punishment such that the agent with the highest effort who caused the greatest damage is punished. Conversely, if the agents' effort constraints are relatively low, in reverse contest B, the designer awards a prize to the agent with the lowest effort who caused the smallest damage. We analyze the behavior of both symmetric and asymmetric agents in both contests A and B. In equilibrium, independent of the levels of the agents' effort constraints, both agents are active and they have positive expected payoffs. Furthermore, the agents might have the same expected payoff regardless of their asymmetric values of the prize/punishment or their asymmetric effort constraints. 
Date:  2020–02 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14411&r=all 
By:  Yuval Heller; Erik Mohlin 
Abstract:  We develop a framework in which individuals' preferences coevolve with their abilities to deceive others about their preferences and intentions. Specifically, individuals are characterised by (i) a level of cognitive sophistication and (ii) a subjective utility function. Increased cognition is costly, but higherlevel individuals have the advantage of being able to deceive lowerlevel opponents about their preferences and intentions in some of the matches. In the remaining matches, the individuals observe each other's preferences. Our main result shows that, essentially, only efficient outcomes can be stable. Moreover, under additional mild assumptions, we show that an efficient outcome is stable if and only if the gain from unilateral deviation is smaller than the effective cost of deception in the environment. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.15308&r=all 
By:  Felipe R. Durazzo; David Turchick 
Abstract:  An oftenheard criticism about electoral pollsters is that they might misreport preelection poll results. We show that this can happen even in the absence of partisan motives, but purely for reputational ones. By underreporting the expected number of supporters of the most preferred candidate, the pollster is able to induce an election result more in line with its report. By doing so, not only victory chances of the most preferred candidate in society rise above 50%, but also total election costs are reduced, thus yielding welfare gains. Our model also allows for the accommodation of both the underdog effect (a feature of pivotal voting models) and the apparently inconsistent bandwagon effect, in the sense that the latter may be an illusion on the part of an observer who disregards the possibility of nontruthful polls. All of these results hold even as the electorate size grows without bound. 
Keywords:  costly voting; pivotal voting model; preelection polls; misreporting; bandwagon effect 
JEL:  C70 C72 D72 C46 
Date:  2020–07–09 
URL:  http://d.repec.org/n?u=RePEc:spa:wpaper:2020wpecon10&r=all 
By:  Asriyan, Vladimir; Foarta, Dana; Vanasco, Victoria 
Abstract:  This paper explores the incentives of product designers to complexify products, and the resulting implications for overall product quality. In our model, a consumer can accept or reject a product proposed by a designer, who can affect the quality and the complexity of the product. While the product's quality determines the direct benefits of the product to the consumer, the product's complexity affects how costly it is for this Bayesian consumer to extract information about the product's quality. Examples include banks that design financial products that they later offer to retail investors, or policymakers who propose policies for approval by voters. We find that complexity is not necessarily a feature of low quality products. While an increase in alignment between the consumer and the designer leads to more complex but better quality products, higher product demand or lower competition among designers leads to more complex and lower quality products. Our findings produce novel empirical implications on the relationship between quality and complexity of financial products and regulatory policies, which are consistent with recent evidence. 
Keywords:  Complexity; financial products; Information Acquisition; Information Frictions; Product design; regulation; signaling 
JEL:  D78 D82 D83 G13 
Date:  2020–01 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14307&r=all 
By:  Ajay K. Agrawal; Joshua S. Gans; Scott Stern 
Abstract:  Entrepreneurs must choose between alternative strategies for bringing their idea to market. They face uncertainty regarding both the quality of their idea as well as the efficacy of each strategy. While entrepreneurs can reduce this uncertainty by conducting tests, any single test conflates the signal of the efficacy of the particular strategy and the quality of the idea. Resolving this conflation requires exploring multiple strategies. Consequently, entrepreneurial choice is enhanced by finding ways to lower the cost of testing multiple strategies, receiving guidance as to the types of tests likely to reduce signal conflation, and optimally sequencing tests based on prior beliefs. This creates a role for judgment that may be provided by third parties such as mentors and investors. We hypothesize that institutions that lower the cost of transmitting and aggregating judgment spur entrepreneurial success. 
JEL:  D83 O3 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:nbr:nberwo:27379&r=all 
By:  Steve Alpern; Bo Chen 
Abstract:  We consider an oddsized "jury", which votes sequentially between two states of Nature (say A and B, or Innocent and Guilty) with the majority opinion determining the verdict. Jurors have private information in the form of a signal in [1,+1], with higher signals indicating A more likely. Each juror has an ability in [0,1], which is proportional to the probability of A given a positive signal, an analog of Condorcet's p for binary signals. We assume that jurors vote honestly for the alternative they view more likely, given their signal and prior voting, because they are experts who want to enhance their reputation (after their vote and actual state of Nature is revealed). For a fixed set of jury abilities, the reliability of the verdict depends on the voting order. For a jury of size three, the optimal ordering is always as follows: middle ability first, then highest ability, then lowest. For sufficiently heterogeneous juries, sequential voting is more reliable than simultaneous voting and is in fact optimal (allowing for nonhonest voting). When average ability is fixed, verdict reliability is increasing in heterogeneity. For mediumsized juries, we find through simulation that the median ability juror should still vote first and the remaining ones should have increasing and then decreasing abilities. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.14045&r=all 
By:  Benjamin Heymann (CERMICS); Michel de Lara (CERMICS); JeanPhilippe Chancelier (CERMICS) 
Abstract:  We state and prove Kuhn's equivalence theorem for a new representation of games, the intrinsic form. First, we introduce games in intrinsic form where information is represented by $\sigma$fields over a product set. For this purpose, we adapt to games the intrinsic representation that Witsenhausen introduced in control theory. Those intrinsic games do not require an explicit description of the play temporality, as opposed to extensive form games on trees. Second, we prove, for this new and more general representation of games, that behavioral and mixed strategies are equivalent under perfect recall (Kuhn's theorem). As the intrinsic form replaces the tree structure with a product structure, the handling of information is easier. This makes the intrinsic form a new valuable tool for the analysis of games with information. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.14838&r=all 
By:  Pierpaolo Battigalli; Martin Dufwenberg 
Abstract:  The mathematical framework of psychological game theory is useful for describing many forms of motivation where preferences depend directly on own or others’ beliefs. It allows for incorporating, e.g., emotions, reciprocity, image concerns, and selfesteem in economic analysis. We explain how and why, discussing basic theory, experiments, applied work, and methodology. 
Keywords:  psychological game theory, beliefdependent motivation, reciprocity, emotions, image concerns, selfesteem 
JEL:  C72 D91 
Date:  2020 
URL:  http://d.repec.org/n?u=RePEc:ces:ceswps:_8285&r=all 
By:  Morelli, Massimo; Sasso, Greg 
Abstract:  We explore the consequences of populism for bureaucrats' incentives by analyzing a model of delegated policymaking between politicians and bureaucrats. Populist leaders prefer loyalist bureaucrats over competent ones, and this leads competent bureaucrats to engage in strategic policymaking: they sometimes feign loyalty to the current incumbent; and they sometimes implement the correct policy even at the cost of being fired. We show that feigning loyalty becomes more likely as the probability of a populistloyalist combination increases. We also show that bureaucratic turnover is higher under populists when the bureaucracy is strong and higher under nonpopulists when the bureaucracy is weak. 
Date:  2020–03 
URL:  http://d.repec.org/n?u=RePEc:cpr:ceprdp:14499&r=all 
By:  David McAdams 
Abstract:  This paper develops a Nashequilibrium extension of the classic SIR model of infectiousdisease epidemiology ("Nash SIR"), endogenizing people's decisions whether to engage in economic activity during a viral epidemic and allowing for complementarity in socialeconomic activity. An equilibrium epidemic is one in which Nash equilibrium behavior during the epidemic generates the epidemic. There may be multiple equilibrium epidemics, in which case the epidemic trajectory can be shaped through the coordination of expectations, in addition to other sorts of interventions such as stayathome orders and accelerated vaccine development. An algorithm is provided to compute all equilibrium epidemics. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.10109&r=all 
By:  Kiho Yoon 
Abstract:  This paper examines necessary and sufficient conditions for the uniqueness of dynamic Groves mechanisms when the domain of valuations is restricted. Our approach is to appropriately define the total valuation function, which is the expected discounted sum of each period's valuation function from the allocation and thus a dynamic counterpart of the static valuation function, and then to port the results for static Groves mechanisms to the dynamic setting. 
Date:  2020–06 
URL:  http://d.repec.org/n?u=RePEc:arx:papers:2006.14190&r=all 