Markups and the Welfare Cost of Business Cycles: A Reappraisal

Gali, Gertler, and Lopez‐Salido (2007) recently show quantitatively that fluctuations in the efficiency of resource allocation do not generate sizable welfare costs. In their economy, which is distorted by monopolistic competition in the steady state, we show that they underestimate the welfare cost of these fluctuations by ignoring the negative effect of aggregate volatility on average consumption and leisure. As monopolistic suppliers, both firms and workers aim to preserve their expected markups; the interaction between aggregate fluctuations and price‐setting behavior results in average consumption and employment levels that are lower than their counterparts in the flexible‐price economy. This level effect increases the efficiency cost of business cycles. It is all the more sizable with the degree of inefficiency in the steady state, lower labor–supply elasticities, and when prices instead of wages are rigid.     

Monetary Policy and Asset Prices: A Mechanism Design Approach

We investigate the effects of monetary policy on asset prices in economies where assets are traded periodically in bilateral meetings. The trading mechanism is designed to maximize social welfare taking as given the frictions in the environment and monetary policy. We show that asset price “bubbles” emerge in a constrained‐efficient monetary equilibrium only if liquidity is abundant and the first‐best allocation is implementable. In contrast, if liquidity is scarce, assets are priced at their fundamental value in any constrained‐efficient monetary equilibrium, in which case an increase in inflation has no effect on asset prices, but it reduces output and welfare.     

The Size and Incidence of the Losses from Noise Trading

Recent empirical research has identified a significant amount of volatility in stock prices that cannot easily be explained by changes in fundamentals; one interpretation is that asset prices respond not only to news but also to irrational “noise trading.” We assess the welfare effects and incidence of such noice trading using an overlapping-generations model that gives investors short horizons. We find that the additional risk generated by noise trading can reduce the capital stock and consumption of the economy, and we show that part of that cost may be borne by rational investors. We conclude that the welfare costs of noise trading may be large if the magnitude of noise in aggregate stock prices is as large as suggested by some of the recent empirical litrature on the excess volatility of the market.     

Inflation and Welfare: A Search Approach

This paper uses a search model of monetary exchange to provide new insights for evaluating the welfare costs of inflation. We first show that the search model of money can rationalize the estimates of the welfare cost of inflation based on the "welfare triangle" methodology of Bailey (1956) and Lucas (2000) provided that buyers appropriate the social marginal benefit of their real balances. For other mechanisms, the measure given by the welfare triangle has to be scaled up by a factor that increases with sellers' market power. We introduce capital and endogenous participation decisions and study how the cost of inflation is affected. We provide calibrated examples in which a deviation from the Friedman rule is optimal.     

基金业绩排名与泡沫资产配置

基金在业绩排名压力下的泡沫资产配置行为会加剧市场波动、推升市场泡沫。本文基于事件研究法与固定效应模型研究了2013―2020年基金的重仓持股,发现:(1)基金在泡沫膨胀阶段显著超配了泡沫资产,而在泡沫破裂前后显著减配,展现了“泡沫骑乘者”的特征;(2)2015年前后,泡沫资产主要为小市值股票,2019―2020年,泡沫资产逐渐转为大市值“白马股”,且基金超配的程度显著提高,呈现抱团大盘白马股的特征;(3)排名前5%的赢家基金,以及1/3和1/10关键排名处的基金更激进地超配泡沫资产;(4)相邻排名基金的业绩差异越大,基金的泡沫资产配置行为越明显。综上表明,基金公司并不一定是天然的市场稳定器,监管层应密切关注业绩压力下基金超配泡沫资产的行为,投资者则应理性选择长期声誉较高的基金。     

Price volatility,welfare, and trading hours in asset markets

This paper studies the consequences of opening asset markets more often for the properties of asset prices and social welfare. For all reasonable parameter values, increasing trading hours lowers average asset prices, increases unconditional asset price volatility at a given point in time, and decreases unconditional asset price volatility when averaged over the period of time that includes the additional hours that markets are open. Unconditional social welfare is increased by opening markets more often, although the welfare gains are small – well below 1% of lifetime consumption. In contrast, because expanding hours of trading affects agents' information sets, the welfare effect of more trading hours conditional on information available to agents can be large and the effect can be negative.     

Static and dynamic connectedness between NFTs,Defi and other assets: Portfolio implication

The paper examines the return and volatility transmission between NFTs, Defi assets, and other assets (oil, gold, Bitcoin, and S&P 500) using the TVP-VAR framework. The results report weak static return and volatility spillovers between NFTs and Defi assets and selected markets, showing that these new digital assets are still relatively decoupled from traditional asset classes. Bitcoin, oil, and half of the NFTs and Defi assets are net transmitters of return and volatility spillovers, whereas rest of the markets are net recipients of spillovers. Our findings show that the dynamic return and volatility connectedness become higher during the initial phase of the COVID-19 pandemic and the cryptocurrency bubble of 2021. We also compute the static and dynamic optimal weights, hedge ratios, and hedging effectiveness for the portfolios of NFTs/other asset and Defi asset/other asset and show that investors and portfolio managers should consider adding NFTs and Defi assets in their portfolios of gold, oil, and stock markets to achieve diversification benefits.     

The Cost of Nominal Rigidity in NNS Models

We present a model with Calvo wage and price setting, capital formation, and estimated rules for government spending and monetary policy. Our model captures many aspects of U.S. data, including the volatility that has been observed in various efficiency gaps. We estimate the cost of nominal rigidity—welfare under flexible wages and prices minus welfare with nominal rigidities—to be as much as 3% of consumption each period. Since there are interest rate rules that virtually eliminate this cost, our model suggests that—contrary to Lucas's (2003) assertion—there is considerable room for improvement in demand management policy.     

Price Stability with Imperfect Financial Integration

This paper studies whether the international monetary system can be affected by asymmetries in the cross-country positions in the international financial markets, i.e., the fact that some countries are large debtors while others are creditors. An important channel that is explored is the interaction between international risk sharing and the stabilization role of monetary policy in each country. The main finding is that the welfare costs of incomplete markets and the gains of deviating from a policy of price stability are increasing with the cross-country asymmetries in the initial net international positions and in particular they become nonnegligible when the persistence of the shocks increases (1% of a permanent shift in steady-state consumption, for the welfare costs of incomplete markets, and 0.2%, for the gains of deviating from a policy of price stability). When global imbalances become larger, optimal monetary policy requires an increase in the volatilities of the real returns on assets and in particular of the nominal interest rates, which should happen to be more correlated across countries.     

Home bias,exchange rate disconnect,and optimal exchange rate policy

This paper examines how much the central bank should adjust the interest rate in response to real exchange rate fluctuations. The paper first demonstrates, in a two-country Dynamic Stochastic General Equilibrium (DSGE) model, that home bias in consumption is important to replicate the exchange rate volatility and exchange rate disconnect documented in the data. When home bias is high, the shock to Uncovered Interest rate Parity (UIP) can substantially drive up exchange rate volatility while leaving the volatility of real macroeconomic variables, such as GDP, almost untouched. The model predicts that the volatility of the real exchange rate relative to that of GDP increases with the extent of home bias. This relation is supported by the data. A second-order accurate solution method is employed to find the optimal operational monetary policy rule. Our model suggests that the monetary authority should not seek to vigorously stabilize exchange rate fluctuations. In particular, when the central bank does not take a strong stance against the inflation rate, exchange rate stabilization may induce substantial welfare loss. The model does not detect welfare gain from international monetary cooperation, which extends Obstfeld and Rogoff's [Obstfeld, M., Rogoff, K.,2002. Global implications of self-oriented national monetary rules, Quarterly Journal of Economics May, 503–535] findings to a DSGE model.     

The Life-Cycle Effects of House Price Changes

We develop a life-cycle model that explicitly incorporates the dual feature of housing as both a consumption good and an investment asset. Our analysis indicates that the consumption and welfare consequences of house price changes on individual households vary significantly. In particular, the non-housing consumption of young and old homeowners is much more sensitive to house price changes than that of middle-aged homeowners. More importantly, while house price appreciation increases the net worth and consumption of all homeowners, it only improves the welfare of old homeowners. Renters and young homeowners are worse off due to higher lifetime housing consumption costs.     

Monetary Policy,Asset Prices,and Liquidity in Over‐the‐Counter Markets

We develop a model where agents can allocate their wealth between a liquid asset, which can be used to purchase consumption goods, and an illiquid asset, which represents a better store of value. Should a consumption opportunity arise, agents may visit a frictional “over‐the‐counter” secondary asset market where they can exchange illiquid for liquid assets. We characterize how monetary policy affects both the issue price and the secondary market price of the asset. We also show that, in contrast to conventional wisdom, search and bargaining frictions in the secondary asset market can improve welfare if inflation is low.     

Aggregate implications of micro asset market segmentation

An extensive empirical literature finds that micro asset markets are segmented from one another. We develop a consumption-based asset pricing model to quantify the aggregate implications of a financial system comprised of many such segmented micro asset markets. We specify exogenously the level of segmentation that determines how much idiosyncratic risk traders bear in their micro market and calibrate the segmentation to match facts about systematic and idiosyncratic return volatility. In our benchmark model traders bear 30% of their idiosyncratic risk, the unconditional aggregate equity premium is 2.4% annual, and the welfare costs of segmentation are substantial, 1.8% of lifetime consumption.     

Advisors and asset prices: A model of the origins of bubbles

We develop a model of asset price bubbles based on the communication process between advisors and investors. Advisors are well-intentioned and want to maximize the welfare of their advisees (like a parent treats a child). But only some advisors understand the new technology (the tech-savvies); others do not and can only make a downward-biased recommendation (the old-fogies). While smart investors recognize the heterogeneity in advisors, naive ones mistakenly take whatever is said at face value. Tech-savvies inflate their forecasts to signal that they are not old-fogies, since more accurate information about their type improves the welfare of investors in the future. A bubble arises for a wide range of parameters, and its size is maximized when there is a mix of smart and naive investors in the economy. Our model suggests an alternative source for stock over-valuation in addition to investor overreaction to news and sell-side bias.     

On the aggregate welfare cost of Great Depression unemployment

The potential benefit of policies that eliminate a small likelihood of economic crises is calculated. An economic crisis is defined as an increase in unemployment of the magnitude observed during the Great Depression. For the U.S., the maximum likelihood estimate of entering a depression is found to be about once every 83 years. The welfare gain from setting this small probability to zero can range between 1% and 7% of annual consumption in perpetuity. For most estimates, more than half of these large gains results from a reduction in individual consumption volatility.     

On the Instability of Long‐Run Money Demand and the Welfare Cost of Inflation in the United States

We evaluate the policy implications of measuring the welfare cost of inflation accounting for instabilities in the long‐run money demand for the United States over the period 1900–2013. We extend the analysis and reassess the results reported in Lucas (2000) and Ireland (2009), also considering the recent theoretical contributions of Lucas and Nicolini (2015) and Berentsen, Huber, and Marchesiani (2015). Breaks in the long‐run money demand give rise to regime‐dependent welfare cost estimates. We find that the welfare cost is about 0.1% of annual income over 1976–2013, as compared to 0.8% over 1945–75. Overall, these values are substantially lower than those reported in the literature.     

Asset price bubbles from heterogeneous beliefs about mean reversion rates

Harrison and Kreps showed in 1978 how the heterogeneity of investor beliefs can drive speculation, leading the price of an asset to exceed its intrinsic value. By focusing on an extremely simple market model—a finite-state Markov chain—the analysis of Harrison and Kreps achieved great clarity but limited realism. Here we achieve similar clarity with greater realism, by considering an asset whose dividend rate is a mean-reverting stochastic process. Our investors agree on the volatility, but have different beliefs about the mean reversion rate. We determine the minimum equilibrium price explicitly; in addition, we characterize it as the unique classical solution of a certain linear differential equation. Our example shows, in a simple and transparent manner, how heterogeneous beliefs about the mean reversion rate can lead to everlasting speculation and a permanent “price bubble.”     

Temptation and Self‐Control: Some Evidence and Applications

This paper studies the empirical relevance of temptation and self‐control using household‐level data from the Consumer Expenditure Survey. We construct an infinite‐horizon consumption‐savings model that allows, but does not require, temptation and self‐control in preferences. In the presence of temptation, a wealth–consumption ratio, in addition to consumption growth, becomes a determinant of the asset‐pricing kernel, and the importance of this additional pricing factor depends on the strength of temptation. To identify the presence of temptation, we exploit an implication of the theory that a more tempted individual should be more likely to hold commitment assets such as individual retirement account (IRA) or 401(k) accounts. Our estimation provides empirical support for temptation preferences. Based on our estimates, we explore some quantitative implications of this class of preferences for capital accumulation in a neoclassical growth model and the welfare cost of the business cycle.     

Consumption, the persistence of shocks, and asset price volatility

In a general equilibrium setting, a temporary component in consumption introduces a wedge between the volatility of equity returns and the volatility of consumption growth. This paper explores the asset pricing consequences of this property in a model in which consumption is the sum of a permanent and a transitory component. Permanent shocks are assumed to be rare events, while transitory shocks follow a diffusion process. When calibrated to US annual data, the model matches first and second moments of equity and bond returns for preference parameters within acceptable bounds. Permanent and transitory shocks together explain the equity premium, while transitory shocks alone explain the excess volatility of returns.     

Volatility,the Macroeconomy,and Asset Prices

How important are volatility fluctuations for asset prices and the macroeconomy? We find that an increase in macroeconomic volatility is associated with an increase in discount rates and a decline in consumption. We develop a framework in which cash flow, discount rate, and volatility risks determine risk premia and show that volatility plays a significant role in explaining the joint dynamics of returns to human capital and equity. Volatility risk carries a sizable positive risk premium and helps account for the cross section of expected returns. Our evidence demonstrates that volatility is important for understanding expected returns and macroeconomic fluctuations.