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1.
We model policy interactions in a growing economy. Unemployment can persist and matters for the real wage; conflicting claims underpin inflation outcomes; and aggregate demand determines capacity utilization and unemployment. Monetary policy is characterized by a Taylor rule. Fiscal policy is characterized by a marginal tendency to run deficits or surpluses. We address three questions: can monetary policy ensure macroeconomic stability in the absence of coordinated fiscal policy, can fiscal policy ensure macroeconomic stability when the monetary authority pegs the interest rate, and can policy authorities trade‐off some sustained inflation for a long‐run improvement in unemployment rates?  相似文献   

2.
We analyze the behavior of the implied volatility smile for options close to expiry in the exponential Lévy class of asset price models with jumps. We introduce a new renormalization of the strike variable with the property that the implied volatility converges to a nonconstant limiting shape, which is a function of both the diffusion component of the process and the jump activity (Blumenthal–Getoor) index of the jump component. Our limiting implied volatility formula relates the jump activity of the underlying asset price process to the short‐end of the implied volatility surface and sheds new light on the difference between finite and infinite variation jumps from the viewpoint of option prices: in the latter, the wings of the limiting smile are determined by the jump activity indices of the positive and negative jumps, whereas in the former, the wings have a constant model‐independent slope. This result gives a theoretical justification for the preference of the infinite variation Lévy models over the finite variation ones in the calibration based on short‐maturity option prices.  相似文献   

3.
When a set of industries is kept in long‐run equilibrium, it is never possible to change just one price at a time. But when various (or all) prices are changing, the direction of change of any one price can depend on the numéraire adopted. What does it mean, then, to say that a long‐run supply curve is upward (or downward) sloping? Can this qualitative property be independent of the numéraire in terms of which the product price is being measured? In general, it cannot.  相似文献   

4.
A central tenet of the so‐called new consensus view in macroeconomics is that there is no long‐run trade‐off between inflation and unemployment. The main policy implication of this principle is that all monetary policy can aim for is (modest) short‐run output stabilization and long‐run price stability, i.e. monetary policy is neutral with respect to output and employment in the long run. However, research on the different sources of path dependency in the economy suggests that persistent but nevertheless transitory changes in aggregate demand may have a permanent effect on output and employment. If this is the case, then, the way monetary policy is run does have long‐run effects on real variables. This paper provides an overview of this research and explores conceptually how monetary policy should be implemented once these long‐run effects are acknowledged.  相似文献   

5.
We consider the portfolio choice problem for a long‐run investor in a general continuous semimartingale model. We combine the decision criterion of pathwise growth optimality with a flexible specification of attitude toward risk, encoded by a linear drawdown constraint imposed on admissible wealth processes. We define the constrained numéraire property through the notion of expected relative return and prove that drawdown‐constrained numéraire portfolio exists and is unique, but may depend on the investment horizon. However, when sampled at the times of its maximum and asymptotically as the time‐horizon becomes distant, the drawdown‐constrained numéraire portfolio is given explicitly through a model‐independent transformation of the unconstrained numéraire portfolio. The asymptotically growth‐optimal strategy is obtained as limit of numéraire strategies on finite horizons.  相似文献   

6.
We consider a class of asset pricing models, where the risk‐neutral joint process of log‐price and its stochastic variance is an affine process in the sense of Duffie, Filipovic, and Schachermayer. First we obtain conditions for the price process to be conservative and a martingale. Then we present some results on the long‐term behavior of the model, including an expression for the invariant distribution of the stochastic variance process. We study moment explosions of the price process, and provide explicit expressions for the time at which a moment of given order becomes infinite. We discuss applications of these results, in particular to the asymptotics of the implied volatility smile, and conclude with some calculations for the Heston model, a model of Bates and the Barndorff‐Nielsen–Shephard model.  相似文献   

7.
The idea of demand‐led growth is defended by neo‐Kaleckians and neo‐Keynesians using very specific assumptions. In their models the paradox of costs is always valid in the long run. The central message of this paper is that these specific and strong assumptions are not needed to defend the Kaleckian perspective of a demand‐driven long‐run growth. What is needed is simply a less demanding theory of flexible mark‐ups in an open economy. The formal model developed in this paper shows that long‐run growth may be demand driven even when the paradox of costs does not hold in the long run.  相似文献   

8.
When the planning horizon is long, and the safe asset grows indefinitely, isoelastic portfolios are nearly optimal for investors who are close to isoelastic for high wealth, and not too risk averse for low wealth. We prove this result in a general arbitrage‐free, frictionless, semimartingale model. As a consequence, optimal portfolios are robust to the perturbations in preferences induced by common option compensation schemes, and such incentives are weaker when their horizon is longer. Robust option incentives are possible, but require several, arbitrarily large exercise prices, and are not always convex.  相似文献   

9.
The research presents a model that portrays customer‐focused and information‐focused capabilities as interrelated predictors of firm performance. Results show that customer‐focused capabilities are directly related to performance, but that information‐focused capabilities are not. Rather, the latter relationship is indirect: information‐focused capabilities are linked to performance via the interrelationship with customer‐focused capabilities.  相似文献   

10.
To assure price admissibility—that all bond prices, yields, and forward rates remain positive—we show how to control the state variables within the class of arbitrage‐free linear price function models for the evolution of interest rate yield curves over time. Price admissibility is necessary to preclude cash‐and‐carry arbitrage, a market imperfection that can happen even with a risk‐neutral diffusion process and positive bond prices. We assure price admissibility by (i) defining the state variables to be scaled partial sums of weighted coefficients of the exponential terms in the bond pricing function, (ii) identifying a simplex within which these state variables remain price admissible, and (iii) choosing a general functional form for the diffusion that selectively diminishes near the simplex boundary. By assuring that prices, yields, and forward rates remain positive with tractable diffusions for the physical and risk‐neutral measures, an obstacle is removed from the wider acceptance of interest rate methods that are linear in prices.  相似文献   

11.
We discuss the effects of rising shareholder power on distribution and capital accumulation in a Kaleckian model. In the short run, increasing shareholder power may have either positive (‘finance‐led’), negative (‘normal’) or ‘intermediate’ (‘profits without investment’) effects on capacity utilization, profits and capital accumulation. In the medium run, the positive (‘finance‐led’) effects may be maintained in a stable regime under very special conditions, whereas the negative (‘normal’) and the ‘intermediate’ (‘profits without investment’) effects turn into disequilibrium processes with falling rates of capital accumulation and rising outside finance–capital ratios. Therefore, this process gives rise to a ‘paradox of outside finance’.  相似文献   

12.
When the mathematical concept of genericity was arrived at in economics, it was meant more or less as a synonym for generality. Referring to constant return production economies, we will argue that this is not always the case. In particular, the representation of technology that is mathematically generic is not at all general for economists. We will see that in cases that are economically general, but not mathematically generic, activity‐level indeterminacy may occur. In these cases, Kehoe's index theorem, a well‐known result of the application of the differentiable approach to production economies, becomes unusable.  相似文献   

13.
This paper presents a dual economy model of the fix‐price/flex‐price kind that explicitly allows for the existence of a government budget constraint in a fully open economy. Both the external and fiscal closures resemble very much the contemporary experience of several Latin American countries, where fiscal discipline and fix exchange rate systems have been the norm. Thus, within the public sector, it is assumed that public investment is the adjustment variable, while foreign reserves variation adjusts the external balance. Short‐run impacts of policy‐induced variables and changes in exogenous external financing are analysed. Relevant trade‐offs, especially between output and inflation, follow from an analysis in which the time perspective is rather short. However, in the medium term, some balancing forces in the economy can moderate the trade‐offs. We show among a wide range of events and policy options that this is the case of debt relief or a concerted lending strategy.  相似文献   

14.
The purpose of this article is to study the level of “in‐stock” customer service performance being offered in the catalog channel of distribution. The article provides benchmark information for the catalog industry. More importantly, the article serves as one test of the effectiveness of the modern supply chain, where the expectation is for near perfect orders. Customer service levels are studied by using an empirical observation methodology in which catalog retailer's in‐stock performance was measured. Comparisons are made across item type, season, retailer type, and days from catalog receipt. Overall, items were out‐of‐stock during 15.9% of all checkpoints, compared to an 11.8% stock‐out rate in an earlier study of bricks and mortar retailers.  相似文献   

15.
This paper examines the simultaneous impact of demand variability, demand skew, and configuration capacity on customer service in a configure‐to‐order environment. Simulation is done in ARENA and data are analyzed using ANOVA and MANOVA. The findings indicate that the factors studied have differential impact on performance both individually and interactively.  相似文献   

16.
In financial markets, liquidity is not constant over time but exhibits strong seasonal patterns. In this paper, we consider a limit order book model that allows for time‐dependent, deterministic depth and resilience of the book and determine optimal portfolio liquidation strategies. In a first model variant, we propose a trading‐dependent spread that increases when market orders are matched against the order book. In this model, no price manipulation occurs and the optimal strategy is of the wait region/buy region type often encountered in singular control problems. In a second model, we assume that there is no spread in the order book. Under this assumption, we find that price manipulation can occur, depending on the model parameters. Even in the absence of classical price manipulation, there may be transaction triggered price manipulation. In specific cases, we can state the optimal strategy in closed form.  相似文献   

17.
This paper empirically investigates the impact of central government budget deficits upon interest rates in Italy. The period studied runs from 1955 to 1989, and annual data are used. The interest rate measure is the ex ante real rate of interest. It is found, using an instrumental variables technique to control for the endogeneity of the budget deficit, that the budget deficit raises the ex ante real interest rate in Italy.  相似文献   

18.
Firms are faced with challenging decisions when capital equipment reaches the end of its designed service life. This research examines the risks of deciding to extend the retirement date of a capital asset in terms of performance and cost and offers recommended actions to mitigate this risk. Through study of the United States Air Force's A‐10 aircraft, the authors analyze one example of decreased performance and increased costs experienced when supply chain implications are not explicitly considered when making service life extension decisions. In this case, the Air Force's efforts to save money through life extension of existing aircraft actually exceeded the seemingly enormous initial investment of acquiring new aircraft. Arguments are presented suggesting the Air Force, in particular, may reap benefits from forming supply chain relationships and creating continuity plans to manage problems such as parts shortages and cost increases when extending the use of capital assets beyond its intended service life.  相似文献   

19.
20.
The discrete‐time mean‐variance portfolio selection formulation, which is a representative of general dynamic mean‐risk portfolio selection problems, typically does not satisfy time consistency in efficiency (TCIE), i.e., a truncated precommitted efficient policy may become inefficient for the corresponding truncated problem. In this paper, we analytically investigate the effect of portfolio constraints on the TCIE of convex cone‐constrained markets. More specifically, we derive semi‐analytical expressions for the precommitted efficient mean‐variance policy and the minimum‐variance signed supermartingale measure (VSSM) and examine their relationship. Our analysis shows that the precommitted discrete‐time efficient mean‐variance policy satisfies TCIE if and only if the conditional expectation of the density of the VSSM (with respect to the original probability measure) is nonnegative, or once the conditional expectation becomes negative, it remains at the same negative value until the terminal time. Our finding indicates that the TCIE property depends only on the basic market setting, including portfolio constraints. This motivates us to establish a general procedure for constructing TCIE dynamic portfolio selection problems by introducing suitable portfolio constraints.  相似文献   

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