Vicious and virtuous circles — The political economy of unemployment in interwar UK and USA

This paper develops a political economy model of multiple unemployment equilibria to provide a theory of an endogenous natural rate of unemployment for the UK and the US interwar period. The theory here sees the natural rate and the associated path of unemployment as a reaction to mainly demand shocks and the institutional structure of the economy. The channel through which these two forces feed on each other is a political economy process whereby voters with limited information on the natural rate react to shocks by demanding more or less social protection. The reduced form results confirm a pattern of unemployment behaviour in which unemployment moves between high and low equilibria in response to shocks.     

Local Sunspot Equilibria Reconsidered

We generalize the usual notion of local sunspot equilibria. We say such equilibria exist around a steady state of an OLG economy whenever stationary sunspot equilibria of arbitrarily close economies exist within any neighborhood of the steady state. Unlike the usual notion, this generalization allows to address the following identification problem: Can an analyst distinguish empirically small fluctuations due to small shocks to the fundamentals from pure expectations-driven fluctuations? We study conditions under which these generalized local sunspot equilibria exist in OLG economies, and show that they may exist around not only indeterminate but also determinate steady states.     

Political Equilibria with Social Security

We model pay-as-you-go social security systems as the outcome of majority voting within a overlapping generations model with production. When voting, individuals make two choices, pay the elderly their pensions or default, which amount to promise themselves next period. Under general circumstances, there exist equilibria where pensions are voted into existence and maintained. Our analysis uncovers two reasons for this. The traditional one relies on intergenerational trade and occurs at inefficient equilibria. A second reason relies on the monopoly power of the median voter. It occurs when a reduction in current saving induces a large enough increase in future return on capital to compensate for the negative effect of the tax. We characterize the steady state and dynamic properties of these equilibria and study their welfare properties. Journal of Economic Literature Classification Numbers: C72, C78,     

Public debt and social security: Level of formality matters

This paper presents a contribution to the empirical literature concerning the relationship between social security and public debt in emerging economies. In particular, several economic and social shocks, as income inequality, were considered in the analysis. Based on the Brazilian data from 2004 to 2010, and taking into account the effects of shocks on variables which are essential to the public debt and the social security deficit, two sets of GMM models were considered. Furthermore, with the objective of testing the results, a GMM system model was built. The findings confirmed that the social security deficit significantly contributes to an increase in the public debt. Regarding the effects on social security, it was observed that an increase in the level of formality in the economy reduces the deficit. In contrast, a reduction in income inequality, real increase in the minimum wage, and increase in health benefits imply an increase in the social security deficit. Therefore, these variables play a crucial role in the search for an efficient social security management system and cannot be overlooked in ensuring fiscal sustainability.     

Social security and risk sharing

In this paper we identify conditions under which the introduction of a pay-as-you-go social security system is ex ante Pareto-improving in a stochastic OLG economy with capital accumulation and land. We argue that these conditions are consistent with realistic specifications of the parameters of the economy. In our model financial markets are complete and competitive equilibria interim Pareto efficient. Therefore, a welfare improvement can only be obtained if agents? welfare is evaluated ex ante, and arises from an improvement in intergenerational risk sharing. We also examine the optimal size of a given social security system as well as its optimal reform.     

Career length: Effects of curvature of earnings profiles,earnings shocks,taxes, and social security

The same high labor supply elasticity that characterizes a representative family model with indivisible labor and employment lotteries also emerges without lotteries when self-insuring individuals choose interior solutions for their career lengths. Off corners, the more elastic is an earnings profile to accumulated working time, the longer is a workerʼs career. Negative (positive) unanticipated earnings shocks reduce (increase) the career length of a worker holding positive assets, while the effects are the opposite for a worker with negative assets. By inducing a worker to retire at an official retirement age, government provided social security can attenuate responses of career lengths to earnings profile slopes, earnings shocks, and taxes.     

A welfare analysis of social security in a dynastic framework*

In this article, we study the welfare effects of unfunded social security in a general equilibrium model populated with overlapping generations of altruistic individuals that differ in lifetime expectancy and earnings ability. Contrary to previous research, our results indicate that steady‐state welfare increases with social security for most households, although by very different amounts. This result is mainly due to two factors. First, the presence of two‐sided altruism significantly mitigates the crowding out effect of unfunded social security. Second, ability shocks and uncertain lifetimes generate significant heterogeneity among households to yield different induced preferences for social security.     

Multiple equilibria, coordination, and transitional growth

We study a small open economy with two sectors and two factors of production. In one of the sectors, external economies of scale are generated through the industry-level capital input. This leads to a divergence between private and social production possibility frontiers as well as to multiple equilibria. The equilibrium selection problem that arises is solved by agents who follow a simple trial-and-error learning rule. The growth path of the economy as agents learn lies below the production possibility frontier and may display cyclical transitional dynamics. We also show that coordination problems which may prevent the economy from attaining the “good” equilibrium may be alleviated by the temporary use of policy instruments that shape the allocation of resources.     

Microeconomic uncertainty and macroeconomic indeterminacy

We propose a stylized intertemporal macroeconomic model wherein the combination of decentralized trading and microeconomic uncertainty (taking the form of privately observed and uninsured idiosyncratic shocks) creates an information problem between agents and generates indeterminacy of the macroeconomic equilibrium. For a given value of the economic fundamentals, the economy admits a continuum of equilibria that can be indexed by the sales expectations of firms at the time of investment. The Walrasian equilibrium is one of these possible equilibria but it is reached only if firms are optimistic enough. With a weaker degree of optimism, equilibrium output, employment and real wages will be lower than in the Walrasian equilibrium. Moreover, the range of possible equilibria will depend positively on the wage elasticity of the labour supply and on the magnitude of the information problem between buyers and sellers (in our case, the variance of the idiosyncratic shocks).Stochastic simulations performed on a calibrated version of the model show that pure demand expectation shocks may generate business cycle statistics that are not inconsistent with the observed ones.     

金融危机下煤炭产业转型发展思考

煤炭工业是我国重要的能源产业,煤炭工业的健康发展事关国民经济发展和能源安全大局,在长期发展过程中,我国煤炭工业对国民经济和社会发展发挥了重要作用。2008年受金融危机影响,煤炭行业出现产量下滑、价格震荡、企业效益下滑等问题,对煤炭产业的健康发展造成极大影响。对金融危机影响下煤炭产业发展现状及面临问题进行了分析研究,并提出了应对金融危机实现煤炭产业转型发展的对策措施。     

Competitive equilibria of economies with a continuum of consumers and aggregate shocks

This paper studies competitive equilibria of a production economy with aggregate productivity shocks. There is a continuum of consumers who face borrowing constraints and individual labor endowment shocks. The dynamic economy is described in terms of sequences of aggregate distributions. The existence of competitive equilibrium is proven and a recursive characterization is established. In particular, it is shown that for any competitive equilibrium, there is a payoff equivalent competitive equilibrium that is generated by a suitably defined recursive equilibrium.     

The farm, the city, and the emergence of social security

We study the social, demographic and economic origins of social security. The data for the U.S. and for a cross section of countries suggest that urbanization and industrialization are associated with the rise of social insurance. We describe an OLG model in which demographics, technology, and social security are linked together in a political economy equilibrium. In the model economy, there are two locations (sectors), the farm (agricultural) and the city (industrial) and the decision to migrate from rural to urban locations is endogenous and linked to productivity differences between the two locations and survival probabilities. Farmers rely on land inheritance for their old age and do not support a pay-as-you-go social security system. With structural change, people migrate to the city, the land loses its importance and support for social security arises. We show that a calibrated version of this economy, where social security taxes are determined by majority voting, is consistent with the historical transformation in the United States.     

RECURSIVE EQUILIBRIA IN AN AIYAGARI‐STYLE ECONOMY WITH PERMANENT INCOME SHOCKS

We prove existence of a recursive competitive equilibrium (RCE) for an Aiyagari‐style economy with permanent income shocks and derive important economic implications. We show that there exist equilibria where borrowing constraints are never binding and establish a nontrivial lower bound on the equilibrium interest rate. These results imply distinct consumption dynamics compared to existing studies. We present a new approach to solve the agent's problem that uses lattices of consumption functions to deal with permanent income shocks and an unbounded utility function. The approach provides a theoretical foundation for convergence of the time iteration algorithm widely used in applied work.     

Capital Accumulation in a Stochastic Overlapping Generations Model with Social Security

This paper analyzes the impact of pay-as-you-go financed social security on the stochastic process for the capital stock in a stochastic overlapping generations model. It is shown that the probability distribution of the capital stock in absence of social security dominates that in a pay-as-you-go system in the sense of stochastic dominance. Furthermore, the study demonstrates that the sufficient conditions ensuring the existence and uniqueness of stationary equilibria in a pay-as-you-go system are more restrictive than in the model without social security. Journal of Economic Literature Classification Numbers: C62, H55.     

A Theory of Liquidity and Regulation of Financial Intermediation

This paper studies a Diamond–Dybvig model of providing insurance against unobservable liquidity shocks in the presence of unobservable trades. We show that competitive equilibria are inefficient. A social planner finds it beneficial to introduce a wedge between the interest rate implicit in optimal allocations and the economy's marginal rate of transformation. This improves risk sharing by reducing the attractiveness of joint deviations where agents simultaneously misrepresent their type and engage in trades on private markets. We propose a simple implementation of the optimum that imposes a constraint on the portfolio share that financial intermediaries invest in short-term assets.     

Trade,poverty, and social protection in developing countries

How do shifts in trade affect social protections for the poor? Although the fraction of the world's population considered the “extreme” poor has fallen by over one-half over the past quarter century, many of those lifted above the global poverty line remain vulnerable to shocks that could place them back into poverty. These are the groups that require social protection to stabilize their incomes. Among the shocks to which the absolute poor have been exposed are those created by trade liberalization, particularly of the agricultural sector. The resulting risks, uncertainties, and threats to social stability from this type of trade require that the poor be provided with some forms of adjustment assistance. We examine the effects of trade components on several dimensions of social protection in developing countries, including spending, coverage, and adequacy over the past two decades. We find that, contrary to previous studies, disaggregating trade may be a key to determining which international market variables drive expansion of social protection. Disaggregating trade balances in agricultural vs. manufactured goods reveals that net food and agricultural exporters provide better social protection than countries that report agricultural trade deficits. Meanwhile, countries with manufacturing trade surpluses tend to experience reduced social protection coverage. We reason that governments of net agricultural exporters face incentives to invest in social programs that extend eligibility to the rural poor. Manufacturing export-driven economies, on the other hand, are likely participants in global production chains that limit the capacity of the public sector to extend social protection.     

Bones for Sale: 'Development', environment and food security in East Africa

Maasai pastoralism has been characterized historically by highly developed herd and rangeland management techniques and social and cultural institutions at the intra- and inter-community levels that have provided security against shocks such as drought, crop failure and epidemic disease. Key to pastoral production was that herd management and milk production were the domain of the individual domestic units--the household or the homestead--while rights to pasture and water resources were communal so as to guarantee access to both dry and wet season grazing. It is this combination of individual and communal resources and inter- and intra-community relations that enabled pastoralism to thrive for millennia. It will be argued that the failure of colonial and neocolonial 'development' policies to recognize these key features of Maasai pastoralism has been at the root of both the crisis of land degradation and the undermining of Maasai and East African food security.     

Macroeconomic tail risk,currency crises and the inter-war gold standard

We introduce macroeconomic tail risk into the canonical global game model of currency crises. The exchange rate peg is attacked if fundamentals reach a critical threshold, or if there is a sufficiently large public shock. Large shocks generate doubt amongst investors about both the state of the world and about what others know, giving rise to multiple equilibria. We find a non-monotonic relationship between tail risk and the probability of (a fundamentals-based) crisis and show how this effect depends on the magnitude and direction of public shocks. We consider the implications of policy intervention and identify conditions under which active intervention produces doubt about the level of fundamentals and, hence, how others will respond. Our analysis clarifies how financial contagion in Europe precipitated the sterling crisis of 1931.     

Learning and Equilibrium Selection in a Monetary Overlapping Generations Model with Sticky Prices

We study adaptive learning in a monetary overlapping generations model with sticky prices and monopolistic competition for the case where learning agents observe current endogenous variables. Observability of current variables is essential for informational consistency of the learning setup with the model setup but generates multiple temporary equilibria when prices are flexible and prevents a straightforward construction of the learning dynamics. Sticky prices overcome this problem by avoiding simultaneity between prices and price expectations. Adaptive learning then robustly selects the determinate (monetary) steady state independent from the degree of imperfect competition. The indeterminate (non-monetary) steady state and non-stationary equilibria are never stable. Stability in a deterministic version of the model may differ because perfect foresight equilibria can be the limit of restricted perceptions equilibria of the stochastic economy with vanishing noise and thereby inherit different stability properties. This discontinuity at the zero variance of shocks suggests one should analyse learning in stochastic models.     

Work values,endogenous sentiments redistribution

We examine the interactions between individual behavior, sentiments and the social contract in a model of rational voting over redistribution. Agents have moral “work values”. Individuals' self-esteem and social consideration of others are endogenously determined comparing behaviors to moral standards. Attitudes toward redistribution depend on self-interest and social preferences. We characterize the politico-economic equilibria in which sentiments, labor supply and redistribution are determined simultaneously. The equilibria feature different degrees of “social cohesion” and redistribution depending on pre-tax income inequality. In clustered equilibria the poor are held partly responsible for their low income since they work less than the moral standard and hence redistribution is low. The paper proposes a novel explanation for the emergence of different sentiments and social contracts across countries. The predictions appear broadly in line with well-documented differences between the United States and Europe.