Consumption habits in an overlapping-generations model

This paper introduces consumption habits in the Blanchard (1985) overlapping-generations model. It shows that steady-state capital and consumption are higher if individuals have habits than otherwise. Moreover, “inward habits” lead to higher steady-state capital and consumption compared to “outward habits.”     

Public goods, merit goods, and the relation between private and government consumption

In this paper, we investigate the relation between public and private consumption, by constructing a general government spending data set, by function, for 12 European countries. In particular, we split government consumption into two categories. The first category—“public goods”—includes defence, public order, and justice. The second category—“merit goods”—includes health, education, and other services that could have been provided privately. Equations from a relatively general permanent income model are estimated by GMM. The estimates are fairly robust in showing that public goods substitute while merit goods complement private consumption. However, the relation between merit goods and private goods turns out to be stronger than that between public goods and private goods. Thus, in the aggregate government and private consumption are complements.     

Crime and punishment in the “American Dream”

We observe that countries where belief in the “American dream”(i.e., effort pays) prevails also set harsher punishment for criminals. We know that beliefs are also correlated with several features of the economic system (taxation, social insurance, etc). Our objective is to study the joint determination of these three features (beliefs, punitiveness and economic system) in a way that replicates the observed empirical patterns. We present a model where beliefs determine the types of contracts that firms offer and whether workers exert effort. Some workers become criminals, depending on their luck in the labor market, the expected punishment, and an individual shock that we call “meanness”. It is this meanness level that a penal system based on “retribution” tries to detect when deciding the severity of the punishment. We find that when initial beliefs differ, two equilibria can emerge out of identical fundamentals. In the “American” (as opposed to the “French”) equilibrium, belief in the “American dream” is commonplace, workers exert effort, there are high powered contracts (and income is unequally distributed) and punishments are harsh. Economists who believe that deterrence (rather than retribution) shapes punishment can interpret the meanness parameter as pessimism about future economic opportunities and verify that two similar equilibria emerge.     

Convergence of consumption patterns during macroeconomic transition: A model of demand in Ireland and the OECD

This study uses country-level panel data on consumption in Ireland and seven other OECD countries to examine the evolution of Irish consumption patterns as Ireland underwent rapid macroeconomic growth. Consumption levels obviously increased due to substantially higher incomes, but it is less clear how the shares of different types of goods purchased have changed or whether Ireland's consumption mix has converged with that of other high-income countries. Rankings based on a simple distance measure of consumption similarity suggest that Ireland moved from a “low-income” pattern similar to Portugal or Greece to a “high-income” pattern like that of Canada between 1995 and 2003. Using static and dynamic Almost Ideal Demand System models, we first estimate long- and short-run Irish price and income elasticities for nine categories of commodities between 1976 and 2003. These results provide evidence of substantial habit formation in aggregate consumption. We then estimate a long-run cross-country model covering six aggregate commodity groups between 1975 and 2003. The analysis shows that Ireland's demand parameters remain more similar to those of Greece than to higher-income OECD countries in the sample. Although Ireland has overtaken most other OECD countries in per capita income, it is still converging to a higher-income consumption pattern. We foresee further convergence of Irish expenditure patterns towards a pattern typical of high-income countries.     

Is there a “reform fatigue” in the euro area?

The absence of monetary policy within a currency union increases the need for structural reforms that make the participating economies more flexible. However, the absence of exchange rate risk with respect to the other members of the union may reduce the urgency for such reforms. A number of other considerations also suggest that theory is ambiguous about the impact of participating in a currency union on progress in structural reforms. This paper addresses this issue empirically for the euro area. The results suggest that reforms in the euro area seem to have decelerated following the introduction of the euro, but from a fast pace. The paper discusses a number of possible explanations, including “reform fatigue,” the absence of “market punishment,” and “good-times” complacency. Estimates from an empirical growth model suggest that the slowing of reforms may slow down annual output growth by up to 0.2%. However, the results are preliminary and depend on the area of reform considered. Furthermore, the reform dynamics may change with the euro area starting slowing at the end of 2007.     

A portfolio choice model with utility from anticipation of future consumption and stock market mean reversion

This paper studies a consumption and portfolio choice problem of a long-lived investor who derives pleasure not only from current consumption, but also from the contemplation of future consumption. The model assumes that all effects of future consumption on current well being are assumed to enter through a single variable—namely, the “stock of future consumption”—analogously to habit-formation models. The main implications of the model concern the incentives for savings, and the fundamental sources of risk in financial markets. It is shown that, when the stock market exhibits mean reversion, deriving utility from anticipation of future consumption has a tremendous effect on portfolio choice. In particular, mean allocation to stocks is much lower under the proposed preferences relative to the standard preferences, especially for high risk averse investors.     

Pollution and life expectancy: How environmental policy can promote growth

This article investigates the influence of environmental policy (EP) on growth in an AK-type growth model, when finite lifetime is introduced and the link between pollution and life expectancy (through the detrimental impact of pollution on health) is taken into account.Using an overlapping generations model à la Blanchard [Blanchard, O. (1985). Debt, deficits and finite horizon. Journal of Political Economy, 93:223-247], we demonstrate that finite lifetime introduces a “generational turnover effect” which modifies the influence of the EP on growth. Thus, when lifetime is finite and independent from pollution, we show that the “generational turnover effect” limits the detrimental impact of the EP on growth, if agents smooth their consumption over time. When pollution negatively influences life expectancy through health, we demonstrate that the “generational turnover effect” is magnified and that the EP and growth have an inverted U-shaped relationship in the steady-state. In this case, we show that the environmental policy is more likely to promote growth (i.e. it stimulates growth for a wider range of environmental taxes) when the impact of pollution on health is important and/or public expenditures in health are low. Finally, using numerical simulations, we find that for the value of parameters that we have chosen, the EP will be more likely to promote growth when agents smooth consumption over time.     

On S-curves and tipping points

In his discussion in this journal of Kurzweil's The Singularity is Near, Modis criticizes Kurzweil's loose characterization of the “knee” of a growth curve. Likewise, the “tipping points” described by Gladwell (The Tipping Point) are clearly relevant to forecasting systems, but Gladwell did not mathematically identify such points. Both concepts refer to a point on the curve where growth accelerates dramatically and sustains itself. What can be said in a rigorous way about knees and tipping points in growth systems?The answer has to do with the number of parameters of the growth curve, and the (probabilistic) model underlying the growth curve. Using probability theory and computational experiments, this paper clarifies these points for the logistic and Bass curves (identifying an unambiguous tipping point for the latter), and explores the merits of a 3-parameter model of innovation adoption. It concludes that if forecasters are to deal scientifically with the now-established management notion of “tipping points,” a 3-parameter model is needed. The paper also resolves four minor but annoying paradoxes in the growth curve literature.     

Bargaining power and enforcement in credit markets

In a credit market with enforcement constraints, we study the effects of a change in the outside options of a potential defaulter on the terms of the credit contract, as well as on borrower payoffs. The results crucially depend on the allocation of “bargaining power” between the borrower and the lender. We prove that there is a crucial threshold of relative weights such that if the borrower has power that exceeds this threshold, her expected utility must go up whenever her outside options come down. But if the borrower has less power than this threshold, her expected payoff must come down with her outside options. In the former case a deterioration in outside options brought about, say, by better enforcement, must create a Lorenz improvement in state-contingent consumption. In particular, borrower consumption rises in all “bad” states in which loans are taken. In the latter case, in contrast, the borrower's consumption must decline, at least for all the bad states. These disparate findings within a single model permit us to interpret existing literature on credit markets in a unified way.     

Financial development,institutional quality and maximizing-growth trade-off in government finance

This paper studies monetary and fiscal policies in an endogenous growth model with transaction costs. We show that the relation between long-run economic growth and both monetary and fiscal policies is subject to threshold effects, a result that gives account of a number of recent empirical findings. Furthermore, the model shows that, to finance public expenditures, growth-maximizing governments must choose relatively high seigniorage (respectively income taxation), if “institutional quality” and “financial development” indicators are low (respectively high). Thus, our model may explain why some governments resort to seigniorage and inflationary finance, and others rather resort to high tax rates, as a result of growth-maximizing strategies in different structural environments (notably concerning institutional and financial development contexts). In addition, the model allows examining how the optimal mix of government finance changes in response to different public debt contexts. A short empirical section confirms our theoretical results.     

Can micro-credit bring development?

We examine the long-run effects of micro-credit on development in an occupational choice model similar to Banerjee and Newman (JPE, 1993). Micro-credit is modeled as a pure improvement in the credit market that opens up self-employment options to some agents who otherwise could only work for wages or subsist. Micro-credit can either raise or lower long-run GDP, since it can lower use of both subsistence and full-scale industrial technologies. It typically lowers long-run inequality and poverty, by making subsistence payoffs less widespread. Thus, an equity-efficiency tradeoff may be involved in the promotion of micro-credit. However, in a worst case scenario, micro-credit has purely negative long-run effects. The key to micro-credit's long-run effects is found to be the “graduation rate”, defined as the rate at which the self-employed build up enough wealth to start full-scale firms. We distinguish between two avenues for graduation: “winner” graduation (of those who earn above-average returns in self-employment) and “saver” graduation (due to gradual accumulation of average returns in self-employment). Long-run development is not attainable via micro-credit if “winner” graduation is the sole avenue for graduation. In contrast, if the saving rate and self-employment returns of the average micro-borrower are jointly high enough, then micro-credit can bring an economy from stagnation to full development through “saver” graduation. Thus the lasting effects of micro-credit may partially depend on simultaneous facilitation of micro-saving. Eventual graduation of the average borrower, rather than indefinite retention, should be the goal of micro-banks if micro-credit is to be a stepping stone to broad-based development rather than at best an anti-poverty tool.     

Are professional forecasts of growth in US business investment rational?

Utilizing comparable time-series forecasts as benchmarks, we document the “weak” and “stronger” rationality of professional forecasts of growth in business investment for 1982-2009. Consistent with these findings, the forecasts are directionally accurate and imply symmetric loss.     

Non-addictive habits: optimal consumption-portfolio policies

We formulate a model of preferences with non-addictive habits, where consumption is required to be non-negative at all times, but can fall below a “standard of living” index that aggregates past consumption. We study the consumption-portfolio problem taking account of the non-negativity constraint on consumption, and provide a constructive proof for the existence of an optimal policy on a finite time-horizon [0,T]. We show that the consumption constraint binds up to an endogenous stopping time τ∗∈[0,T], after which it remains slack until T. A decomposition of constrained consumption involving an Asian average-strike capped call-option is demonstrated.     

The effect of GNP announcements on fluctuations of GNP growth

This paper is an empirical study of the degree in which perceptions affect the evolution of the economy. We study the effects of the announcements that the government makes on GNP growth. These announcements are subject to a substantial degree of noise and its accuracy improves with time. A revised number is published several years after the first announcement was made public. We consider that the final revision is the “true” value of GNP growth. We show that once announcements are taken into account, the true value of GNP growth at time t has no predictive power in determining growth at any future time. All the predictive power lies in the announcements, and not in the true level of growth. Actually, we show that the variable that determines future growth is the unexpected part of the announcements. We also show that announcements affect growth via aggregate investment.     

Animal spirits and the composition of innovation

This paper shows that the Schumpeterian model with both vertical and horizontal innovative research admits many more equilibria than the unique symmetric balanced growth path (BGP) usually highlighted in the literature. Each of a continuum of BGPs is characterized by a different composition of aggregate R&D (vertical versus horizontal).This appears if firms expect self-fulfilling “waves of enthusiasm” in the newly introduced sectors, as is very common in the real world. Pioneers are challenged by more outsiders and the first monopoly of every new good is likely to last less than in more mature industries: By expecting this horizontal innovation is depressed while vertical innovation is more intense. Such “waves of enthusiasm” have a positive effect on growth rates and a negative effect on consumption levels.     

Measuring fossil resource inequality—A case study for the UK between 1968 and 2000

This paper quantifies fossil resource inequalities amongst income quintiles in the UK between 1968 and 2000. It calculates a resource-based Gini coefficient using an input-output based resource allocation model.The results show that the Gini coefficient for total fossil resource consumption grew by 24% over the time period. By comparison the Gini coefficient for overall household expenditure rose by only 13%. The increase in resource inequality was prompted by the rising demand by high income quintiles for goods and services such as: “fuel and light” (heating and lighting the home), “car use” (private transportation), “recreation”, “travel” and “other services”. The analysis shows further that the Gini coefficient for “direct” fossil resources (“fuel and light” and “car use”) was lower and rose less steeply than the Gini coefficient for fossil resources embodied in other goods and services (indirect fossil resource requirements).Investigation into the drivers behind direct and indirect resource inequalities suggests a number of policy conclusions. Firstly, it is clear that policy initiatives to reduce fossil resource requirements (and the associated climate change impacts) must pay careful attention to distributional differences. Additionally, increased attention needs to be paid to the inequalities associated with indirect fossil resources consumption as well as the more visible direct resource inequalities.     

Relative importance of sticky prices and sticky information in price setting

The relative importance of price and information stickiness in price setting to model and explain inflation dynamics is investigated in this study. A structural model of inflation is developed and used which combines two different models of price setting behavior: the sticky price model of the New Keynesian literature and the sticky information model of Mankiw and Reis. In a framework similar to the Calvo model, I assume that there are two types of firms. One type of firm chooses its prices optimally through forward-looking behavior—as assumed in the sticky price model. It uses all available information when deciding on prices. The other type of firm sets its prices under the constraint that the information it uses is “sticky”—as assumed in the sticky information model. It collects and processes the information necessary to choose its optimal prices with a delay. This leads to the sticky price–sticky information (SP/SI) Phillips curve that nests the standard sticky price and sticky information models. Estimations of this structural model show that both sticky price and sticky information models are statistically and quantitatively important for price setting. However, the sticky price firms make up the majority of the firms in the economy. The results are robust to alternative sub-samples and estimation methods.     

Arbitrage-free valuation of interest rate securities under forward curves with stochastic speed and acceleration

Arbitrage-free models for valuing interest rate securities posit that stochastic changes in spot or forward interest rates (forward rate “speed”) follow a diffusion process. This paper extends the Heath, Jarrow and Morton [Bond pricing and the term structure of interest rates: a new methodology for contingent claims valuations, Econometrica 60 (1992) 77-105], HJM framework by allowing diffusive shocks to both the “speed” and “acceleration” of forward rates. The arbitrage-free restriction on forward rates is identified and involves volatilities of the speed and acceleration dynamics and their correlation. Although the extended forward rates remain in the diffusive framework and evolve continuously, they may exhibit large changes over short intervals (as with jumps) due to stochastic acceleration. Comparisons of bond prices show that the proposed model generates more complex and intricate shapes for the restricted forward curve with the same number of stochastic factors and volatility.     

Differentiating ambiguity and ambiguity attitude

The objective of this paper is to show how ambiguity, and a decision maker (DM)'s response to it, can be modelled formally in the context of a general decision model. We introduce a relation derived from the DM's preferences, called “unambiguous preference”, and show that it can be represented by a set of probabilities. We provide such set with a simple differential characterization, and argue that it is a behavioral representation of the “ambiguity” that the DM may perceive. Given such revealed ambiguity, we provide a representation of ambiguity attitudes. We also characterize axiomatically a special case of our decision model, the “α-maxmin” expected utility model.