An equilibrium model of wealth distribution

I present an explicitly solved equilibrium model for the distribution of wealth and income in an incomplete-markets economy. I first propose a self-insurance model with an inter-temporally dependent preference [Uzawa, H. 1968. Time preference, the consumption function, and optimal asset holdings. In: Wolfe, J.N. (Ed.), Value, Capital, and Growth: Papers in Honour of Sir John Hicks. Edinburgh University Press, Edinburgh, pp. 485-504]. I then derive an analytical consumption rule which captures stochastic precautionary saving motive and generates stationary wealth accumulation. Finally, I provide a complete characterization for the equilibrium cross-sectional distribution of wealth and income in closed form by developing a recursive formulation for the moments of the distribution of wealth and income. Using this recursive formulation, I show that income persistence and the degree of wealth mean reversion are the main determinants of wealth-income correlation and relative dispersions of wealth to income, such as skewness and kurtosis ratios between wealth and income.     

A leisurely reading of the life-cycle consumption data

A puzzle in consumption theory is the observation of a hump in age-consumption profiles. This paper studies a general equilibrium life-cycle economy with capital in which households include both consumption and leisure in their period utility function. A calibrated version of the model shows that a significant hump in life-cycle consumption is a feature of the equilibrium. Thus inclusion of leisure in household preferences may provide part of the explanation of observed life-cycle consumption humps.     

Current consumption and future income growth: Synthetic panel evidence

Using group means computed from 20 years of high quality survey data, I show a strong and robust relation between households’ consumption growth and subsequent realizations of their income growth, including realizations as distant as six years later. The relation appears in multiple types of variation in income growth: in variation across cohort-education groups, in variation over the life cycle, and in variation over the business cycle. While other explanations are explored, the results are likely due to forward-looking households altering their current consumption in response to information they receive about their income years into the future, information that turns out to be accurate.     

Heterogeneous life-cycle profiles, income risk and consumption inequality

Was the increase in income inequality in the US due to permanent shocks or merely to an increase in the variance of transitory shocks? The implications for consumption and welfare depend crucially on the answer to this question. We use Consumer Expenditure Survey (CEX) repeated cross-section data on consumption and income to decompose idiosyncratic changes in income into predictable life-cycle changes, transitory and permanent shocks and estimate the contribution of each to total inequality. Our model fits the joint evolution of consumption and income inequality well and delivers two main results. First, we find that permanent changes in income explain all of the increase in inequality in the 1980s and 1990s. Second, we reconcile this finding with the fact that consumption inequality did not increase much over this period. Our results support the view that many permanent changes in income are predictable for consumers, even if they look unpredictable to the econometrician, consistent with models of heterogeneous income profiles.     

Financing constraints, irreversibility, and investment dynamics

We develop a model of an industry with many heterogeneous firms that face both financing constraints and irreversibility constraints. We use this model to examine the cyclical behavior of aggregate fixed investment, variable capital investment, and output in the presence of persistent idiosyncratic and aggregate shocks. Our model yields three main results. First, the effect of the irreversibility constraint on fixed capital investment is reinforced by the financing constraint. Second, the effect of the financing constraint on variable capital investment is reinforced by the irreversibility constraint. Finally, the interaction between the two constraints is key for explaining why input inventories and material deliveries of US manufacturing firms are so volatile and procyclical, and also why they are highly asymmetrical over the business cycle.     

Risk preferences in multi-period consumption models, the equity premium puzzle, and habit formation utility

The relationship between the relative risk aversion measure for the utility function for consumption and that for the value function for wealth is a derived relationship whose properties depend on how consumption and wealth are defined and measured. This fact together with information concerning estimates for these two relative risk aversion measures is used to give another perspective on the equity premium puzzle, and to explain why it is that the habit formation utility function is effective in eliminating that puzzle. A time separable utility function that can serve as an alternative to the assumption of habit formation is also presented.     

On the consequences of demographic change for rates of returns to capital, and the distribution of wealth and welfare

This paper employs a multi-country large-scale Overlapping Generations model with uninsurable labor productivity and mortality risk to quantify the impact of the demographic transition towards an older population in industrialized countries on world-wide rates of return, international capital flows and the distribution of wealth and welfare in the OECD. We find that for the U.S. as an open economy, rates of return are predicted to decline by 86 basis points between 2005 and 2080 and wages increase by about 4.1%. If the U.S. were a closed economy, rates of return would decline and wages increase by less. This is due to the fact that other regions in the OECD will age even more rapidly; therefore the U.S. is “importing” the more severe demographic transition from the rest of the OECD in the form of larger factor price changes. In terms of welfare, our model suggests that young agents with little assets and currently low labor productivity gain, up to 1% in consumption, from higher wages associated with population aging. Older, asset-rich households tend to lose, because of the predicted decline in real returns to capital.     

On the optimal timing of capital taxes

For many kinds of capital, depreciation rates change systematically with the age of the capital. Consider an example that captures essential aspects of human capital, both regarding its accumulation and its depreciation: a worker obtains knowledge in period 0, then uses this knowledge in production in periods 1 and 2, and thereafter retires. Here, depreciation accelerates: it occurs at a 100% rate after period 2, and at a lower (perhaps zero) rate before that. The present paper analyzes the implications of non-constant depreciation rates for the optimal timing of taxes on capital income. The main finding is that under natural assumptions, the path of tax rates over time must be oscillatory. Oscillatory tax rates are optimal when depreciation rates accelerate with the age of the capital (as in the above example), and provided that the government can commit to the path of future tax rates but cannot apply different tax rates in a given year to different vintages of capital.     

Consumption and risk sharing over the life cycle

A striking feature of U.S. data on income and consumption is that inequality increases with age. This paper asks if individual-specific earnings risk can provide a coherent explanation. We find that it can. We construct an overlapping generations general equilibrium model in which households face uninsurable earnings shocks over the course of their lifetimes. Earnings inequality is exogenous and is calibrated to match data from the U.S. Panel Study on Income Dynamics. Consumption inequality is endogenous and matches well data from the U.S. Consumer Expenditure Survey. The total risk households face is decomposed into that realized before entering the labor market and that realized throughout the working years. In welfare terms, the latter is found to be more important than the former.     

Buffer stock saving in retirement accounts

We use a dynamic programming model to explore the possibility and extent of precautionary saving in tax-sheltered accounts such as the 401(k). The main policy experiment examines the behavior of saving for different levels of unemployment insurance (UI), which is a perfect substitute for precautionary saving against job loss. Our results indicate that increasing the generosity of UI crowds out 401(k) contributions made by younger workers, who save primarily for precautionary reasons. At the aggregate level, we find that 401(k)s increase national saving and that the magnitude of the effect depends on the generosity of UI.     

Durables, nondurables, down payments and consumption excesses

We examine a model that generalizes the standard buffer-stock model of saving to accommodate durables, nondurables, down payment requirements, and adjustment costs in the durables market. We find that nondurable consumption becomes more volatile relative to income as down payments decrease at the individual and at the aggregate level. Moreover, for plausible parameter values, the model can explain the excess smoothness and excess sensitivity observed in U.S. aggregate data. The result follows from a gradual adjustment of consumption to permanent income shocks when agents attempt to spread out the burden of down payments over time, compounded by slow adjustment due to transaction costs.     

Precautionary Saving and Consumption Smoothing across Time and Possibilities

This paper examines how aversion to risk and aversion to intertemporal substitution determine the strength of the precautionary saving motive in a two-period model with Selden/Kreps–Porteus preferences. For small risks, we derive a measure of the strength of the precautionary saving motive that generalizes the concept of "prudence" introduced by Kimball (1990b) . For large risks, we show that decreasing absolute risk aversion guarantees that the precautionary saving motive is stronger than risk aversion, regardless of the elasticity of intertemporal substitution. Holding risk preferences fixed, the extent to which the precautionary saving motive is stronger than risk aversion increases with the elasticity of intertemporal substitution. We derive sufficient conditions for a change in risk preferences alone to increase the strength of the precautionary saving motive and for the strength of the precautionary saving motive to decline with wealth. Within the class of constant elasticity of intertemporal substitution, constant-relative risk aversion utility functions, these conditions are also necessary.     

Precautionary saving and partially observed income

I propose an intertemporal precautionary saving model in which the agent's labor income is subject to (possibly correlated) shocks with different degrees of persistence and volatility. However, he only observes his total income, not individual components. I show that partial observability of individual components of income gives rise to additional precautionary saving due to estimation risk, the error associated with estimating individual components of income. This additional precautionary saving is higher, when estimation risk is greater. Compared with a precautionary agent who is otherwise identical, but ignores estimation risk, the rational agent consumes less at the beginning of his life, but consumes more later, because of larger wealth accumulated from savings for estimation risk. The utility cost of ignoring estimation risk is also quantified in closed form.     

Financial literacy and consumer credit portfolios

We use survey data from a sample of UK households to analyse the relationship between financial literacy and consumer credit portfolios. We show that individuals who borrow on consumer credit exhibit worse financial literacy than those who do not. Borrowers with poor financial literacy hold higher shares of high cost credit (such as home collected credit, mail order catalogue debt and payday loans) than those with higher literacy. We also show that individuals with poor financial literacy are more likely to lack confidence when interpreting credit terms, and to exhibit confusion over financial concepts. They are also less likely to engage in behaviour which might help them to improve their awareness of the credit market.     

TARP funds distribution and bank loan supply

This paper investigates the determinants of the Troubled Asset Relief Program (TARP) funds distribution to banks and the stimulus effect of TARP investments on credit supply in the economy. Using banks’ political and regulatory connections as instruments, this paper finds that TARP investments increased bank loan supply by an annualized rate of 6.36% for banks with below median Tier 1 capital ratios. This increase is found in all major types of loans and can be translated into $404 billion of additional loans for all TARP banks. On average, TARP banks employed about one-third of their TARP capital to support new loans and kept the rest to strengthen their balance sheets. Furthermore, there is little evidence that loans made by TARP banks had lower quality than those by non-TARP banks. In sum, this paper shows a positive stimulus effect of TARP on credit supply during the 2008–2009 financial crisis.     

Financial literacy and its consequences: Evidence from Russia during the financial crisis

The ability of consumers to make informed financial decisions improves their ability to develop sound personal finance. This paper uses a panel data set from Russia, an economy in which household debt has grown at an astounding rate, to examine the importance of financial literacy and its effects on behavior. The paper studies both the financial and real consequences of financial illiteracy. Even though consumer borrowing increased very rapidly in Russia, only 41% of respondents demonstrate an understanding of interest compounding and only 46% can answer a simple question about inflation. Financial literacy is positively related to participation in financial markets and negatively related to the use of informal sources of borrowing. Moreover, individuals with higher financial literacy are significantly less likely to report experiencing a negative income shock during 2009 and have greater availability of unspent income and higher spending capacity. The relationship between financial literacy and availability of unspent income is higher in 2009, suggesting that financial literacy may better equip individuals to deal with macroeconomic shocks.     

Risk and concentration in payment and securities settlement systems

What drives the intraday patterns of settlement in payment and securities settlement systems? Using a model of the strategic interaction of participants in these systems to capture some stylized facts about the Federal Reserve's Fedwire funds and securities systems, this paper identifies three factors that influence a participant's decision on when to send transactions intraday: cost of intraday liquidity, extent of settlement risk, and system design. With these factors, the model can make predictions regarding the impact of policy on the concentration of transactions, amount of intraday overdrafts, central bank credit exposure, costs to system participants, and other risks.     

Habit formation,surplus consumption and return predictability: International evidence

On an international post World War II dataset, we use an iterated GMM procedure to estimate and test the Campbell and Cochrane (1999, By force of habit: a consumption-based explanation of aggregate stock market behavior. Journal of Political Economy 107, 205–251.) habit formation model with a time-varying risk-free rate. In addition, we analyze the predictive power of the surplus consumption ratio for future stock and bond returns. We find that, although there are important cross-country differences and economically significant pricing errors, for the majority of countries in our sample the model gets empirical support in a variety of different dimensions, including reasonable estimates of risk-free rates. Further, for the majority of countries the surplus consumption ratio captures time-variation in expected returns. Together with the price-dividend ratio, the surplus consumption ratio contains significant information about future stock returns, also during the 1990s. In addition, in most countries the surplus consumption ratio is also a powerful predictor of future bond returns. Thus, the surplus consumption ratio captures time-varying expected returns in both stock and bond markets.