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1.
The well‐known lack of power of unit‐root tests has often been attributed to the short length of macroeconomic variables and also to data‐generating processes (DGPs) departing from the I(1)–I(0) models. This paper shows that by using long spans of annual real gross national product (GNP) and GNP per capita (133 years), high power can be achieved, leading to the rejection of both the unit‐root and the trend‐stationary hypothesis. More flexible representations are then considered, namely, processes containing structural breaks (SB) and fractional orders of integration (FI). Economic justification for the presence of these features in GNP is provided. It is shown that both FI and SB formulations are in general preferred to the autoregressive integrated moving average (ARIMA) [I(1) or I(0)] formulations. As a novelty in this literature, new techniques are applied to discriminate between FI and SB. It turns out that the FI specification is preferred, implying that GNP and GNP per capita are non‐stationary, highly persistent but mean‐reverting series. Finally, it is shown that the results are robust when breaks in the deterministic component are allowed for in the FI model. Some macroeconomic implications of these findings are also discussed.  相似文献   

2.
We consider an economy where firms operate in an imperfectly competitive industry and mutually affect each others’ investment opportunities. Each firm is assumed to face a mutually exclusive choice of investing in either a short‐ or a long‐term project. For example, firm i's commitment to a short‐term project cuts into firm j's market in the short‐term but frees‐up firm j's long‐term market, and vice versa. Our results show that, even in the absence of an owner–manager conflict, the owner anticipates the product market rivalry and optimally compensates their managers with short‐ as well as long‐term compensation. Although the optimal compensation design induces myopic investment decisions, it is shown to be in the owners’ best interest. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

3.
In this paper we examine how the Lee–Carter model fares with Swedish data for the period 1901–2001 and for segments of this period. We have choosen to censor ages less than age 40 as those ages only are of marginal interest to the forecast. At age 40 some 98 to 99 percent of the birth cohorts are survivors. In the study we only consider the unweighted K1 estimates. The Lee–Carter model provides very good fits to the data. When splitting up the base period there seems to be an interaction beween the age and time components of the model. In order to deal with the different phases of falling mortality for males and females possibly one should choose the past 25 years as a base in the model. Selecting the base period is however a judgmental issue depending on the main focus of the forecast. Is it long‐term, short‐term or, as in Sweden, a combination of both.?  相似文献   

4.
We model the dynamic volatility and correlation structure of electricity futures of the European Energy Exchange index. We use a new multiplicative dynamic conditional correlation (mDCC) model to separate long‐run from short‐run components. We allow for smooth changes in the unconditional volatilities and correlations through a multiplicative component that we estimate nonparametrically. For the short‐run dynamics, we use a GJR‐GARCH model for the conditional variances and augmented DCC models for the conditional correlations. We also introduce exogenous variables to account for congestion and delivery date effects in short‐term conditional variances. We find different correlation dynamics for long‐ and short‐term contracts and the new model achieves higher forecasting performance compared \to a standard DCC model. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

5.
This paper emphasizes differences among short‐term contracts in terms of career prospects. Using French data over the 2002–2010 period, we rely on a dynamic model with fixed effects to disentangle state dependence from unobserved heterogeneity. Although fixed‐term contracts may provide a ‘stepping‐stone’ to permanent positions, temporary agency work is hardly better than unemployment in this regard. The Great Recession of 2008 has changed the dynamics on the labor market and amplified the difference between fixed‐term contracts and temporary agency work. For both types of temporary workers, providing overtime work does not significantly increase the transition to permanent employment. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

6.
Abstract In the financial literature, the problem of maximizing the expected utility of the terminal wealth has been investigated extensively (for a survey, see, e.g., Karatzas and Shreve (1998), p. 153, and references therein) by using different approaches. In this paper, we extend the existing literature in two directions. First, we let the utility function U(.) of the financial agent (who is a price taker) be implicitly defined through I(.)=(U (.))–1, which is assumed to be additively separable, i.e., I(.)=∑ k=1 N I k (.). Second, we solve the investment problem in the general affine term structure model proposed by Duffie and Kan (1996) in which the functions I k (.), k=1,...,N are associated to HARA utility functions (with possibly different risk aversion parameters), and we show that the utility maximization problem leads to a Riccati ODE. Moreover, we extend to the multi-factor framework the stability result proved in Grasselli (2003), namely, the almost-sure convergence of the solution with respect to the parameters of the utility function. Mathematics Subject Classification (2000): 91B28 Journal of Economic Literature Classification: G11  相似文献   

7.
In this paper we model Value‐at‐Risk (VaR) for daily asset returns using a collection of parametric univariate and multivariate models of the ARCH class based on the skewed Student distribution. We show that models that rely on a symmetric density distribution for the error term underperform with respect to skewed density models when the left and right tails of the distribution of returns must be modelled. Thus, VaR for traders having both long and short positions is not adequately modelled using usual normal or Student distributions. We suggest using an APARCH model based on the skewed Student distribution (combined with a time‐varying correlation in the multivariate case) to fully take into account the fat left and right tails of the returns distribution. This allows for an adequate modelling of large returns defined on long and short trading positions. The performances of the univariate models are assessed on daily data for three international stock indexes and three US stocks of the Dow Jones index. In a second application, we consider a portfolio of three US stocks and model its long and short VaR using a multivariate skewed Student density. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

8.
This paper provides a model that can account for the almost uniform staggering of wage contracts in some countries as well as for the markedly nonuniform staggering in others. In the model, short and long contracts as well as long contracts concluded in different periods are strategic substitutes, which provide a powerful rationale for staggering. We show that for realistic parameter values, there is a continuum of possible equilibria with various degrees of staggering of long contracts. If the contracting cost is not too large, then the lowest possible degree of staggering decreases with the contracting cost and increases with monetary uncertainty.  相似文献   

9.
Informal learning is an important source of employee adaptability and expertise, yet it is unclear how it may be encouraged through human resource management (HRM) practices. In this study, we investigate how opportunities for formal learning may be used to stimulate short‐ and long‐term participation in informal learning. In addition, we examine whether HRM system strength intensifies the relationship between opportunities for formal learning and informal learning. Using a sample of 430 respondents in 52 teams within six Dutch vocational and educational training schools, we adopt a longitudinal design to examine two types of autonomous informal learning activities (reflection and keeping up to date), and three collaborative activities (asking for feedback, knowledge sharing and innovative behavior) over two years. Opportunity for formal learning was positively related to short‐ and long‐term participation in informal learning activities, with the exception of long‐term innovation. Moreover, HRM system strength intensified these relationships. Managerial implications of these findings for encouraging informal learning activities at work are discussed. © 2016 Wiley Periodicals, Inc.  相似文献   

10.
This article assesses whether short‐lived jobs (lasting one quarter or less and involuntarily ending in unemployment) are stepping stones to long‐lasting jobs (enduring 1 year or more) for Belgian long‐term unemployed school‐leavers. We proceed in two steps. First, we estimate labour market trajectories in a multi‐spell duration model that incorporates lagged duration and lagged occurrence dependence. Second, in a simulation we find that (fe)male school‐leavers accepting a short‐lived job are, within 2 years, 13.4 (9.5) percentage points more likely to find a long‐lasting job than in the counterfactual in which they reject short‐lived jobs.  相似文献   

11.
This paper shows that the properties of nonlinear transformations of a fractionally integrated process strongly depend on whether the initial series is stationary or not. Transforming a stationary Gaussian I(d) process with d>0 leads to a long-memory process with the same or a smaller long-memory parameter depending on the Hermite rank of the transformation. Any nonlinear transformation of an antipersistent Gaussian I(d) process is I(0)). For non-stationary I(d) processes, every polynomial transformation is non-stationary and exhibits a stochastic trend in mean and in variance. In particular, the square of a non-stationary Gaussian I(d) process still has long memory with parameter d, whereas the square of a stationary Gaussian I(d) process shows less dependence than the initial process. Simulation results for other transformations are also discussed.  相似文献   

12.
The innovations representation for a local linear trend can adapt to long run secular and short term transitory effects in the data. This is illustrated by the theoretical power spectrum for the model which may possess considerable power at frequencies that might be associated with cycles of several years' duration. Whilst advantageous for short term forecasting, the model may be of less use when interest is in the underlying long run trend in the data. In this paper we propose a generalisation of the innovations representation for a local linear trend that is appropriate for representing short, medium and long run trends in the data.  相似文献   

13.
This paper suggests a term structure model which parsimoniously exploits a broad macroeconomic information set. The model uses the short rate and the common components of a large number of macroeconomic variables as factors. Precisely, the dynamics of the short rate are modeled with a Factor-Augmented Vector Autoregression and the term structure is derived using parameter restrictions implied by no-arbitrage. The model has economic appeal and provides better out-of-sample yield forecasts at intermediate and long horizons than a number of previously suggested approaches. The forecast improvement is highly significant and particularly pronounced for short and medium-term maturities.  相似文献   

14.
This paper considers structural models with both I(1) and I(0) variables. The structural shocks associated with either set of variables could be permanent or transitory. We classify the shocks as (P1,P0) and (T1,T0), where P/T distinguishes permanent/transitory, while 1/0 means they are attached to structural equations with either I(1) or I(0) variables as their ‘dependent’ variable. We show that P0 shocks can affect cointegration analysis and provide a formula to compute the permanent component if they are present. Finally, we reformulate a well‐known empirical structural vector autoregression showing the impact of P0 shocks when there are just long‐run parametric and sign restrictions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
With cointegration tests often being oversized under time‐varying error variance, it is possible, if not likely, to confuse error variance non‐stationarity with cointegration. This paper takes an instrumental variable (IV) approach to establish individual‐unit test statistics for no cointegration that are robust to variance non‐stationarity. The sign of a fitted departure from long‐run equilibrium is used as an instrument when estimating an error‐correction model. The resulting IV‐based test is shown to follow a chi‐square limiting null distribution irrespective of the variance pattern of the data‐generating process. In spite of this, the test proposed here has, unlike previous work relying on instrumental variables, competitive local power against sequences of local alternatives in 1/T‐neighbourhoods of the null. The standard limiting null distribution motivates, using the single‐unit tests in a multiple testing approach for cointegration in multi‐country data sets by combining P‐values from individual units. Simulations suggest good performance of the single‐unit and multiple testing procedures under various plausible designs of cross‐sectional correlation and cross‐unit cointegration in the data. An application to the equilibrium relationship between short‐ and long‐term interest rates illustrates the dramatic differences between results of robust and non‐robust tests.  相似文献   

16.
In this paper, an empirically stable money demand model for M3 in the euro area is constructed. Starting with a multivariate system, three cointegrating relationships with economic content are found: (i) the spread between the long‐term and the short‐term nominal interest rates, (ii) the long‐term real interest rate, and (iii) a long‐run demand for broad money M3. There is evidence that the determinants of M3 money demand are weakly exogenous with respect to the long‐run parameters. Hence, following a general‐to‐specific modelling approach, a parsimonious conditional error‐correction model for M3 money demand is derived which can be interpreted economically. For the conditional model, long‐run and short‐run parameter stability is extensively tested and not rejected. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

17.
This study provides recent empirical evidence on the impact of the federal budget deficit on the ex ante real interest rate yield on Moody’s Baa-rated corporate bonds. The study is couched within an open loanable funds model that includes the ex ante real short term real interest rate, the M1 money supply, net international capital inflows, and the unemployment rate. Using quarterly data for the period 1973.1–2007.4, two-stage least squares estimation reveals that the federal budget deficit, expressed as a percent of GDP, exercised a positive and statistically significant impact on the ex ante real interest rate yield on these corporate issues.  相似文献   

18.
This paper studies the predictive ability of a variety of models in forecasting the yield curve for the Brazilian fixed income market. We compare affine term structure models with a variation of the Nelson–Siegel exponential framework developed by Diebold and Li [Diebold, F., & Li, C. (2006). Forecasting the Term Structure of Government Yields. Journal of Econometrics, 130, 337–364]. Empirical results suggest that forecasts made with the latter methodology are superior, and appear to be more accurate at long horizons than other different benchmark forecasts. These results are important for policy-makers, as well as for portfolio and risk managers. Further research could study the predictive ability of such models in other emerging markets.  相似文献   

19.
This is an experimental study of communication and information transparency in one‐shot labor market relations with incomplete contracts. We find that communication in the form of non‐binding broadcast chat messages increases wages, effort levels, and overall efficiency regardless of the information regime. It serves as a negotiation platform and helps workers and firms learn how to cooperate. Communication outperforms information transparency in motivating trust and cooperative behavior in one‐shot interactions. Although transparency might be important in the long term, it does not improve any of the market outcomes in short‐term relations unless it is combined with communication. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

20.
Milan Stehlík 《Metrika》2003,57(2):145-164
The aim of this paper is to give some results on the exact density of the I-divergence in the exponential family with gamma distributed observations. It is shown in particular that the I-divergence can be decomposed as a sum of two independent variables with known distributions. Since the considered I-divergence is related to the likelihood ratio statistics, we apply the method to compute the exact distribution of the likelihood ratio tests and discuss the optimality of such exact tests. One of these tests is the exact LR test of the model which is asymptotically optimal in the Bahadur sense. Numerical examples are provided to illustrate the methods discussed. Received: January 2002 Acknowledgements. I am grateful to Prof. Andrej Pázman for helpful discussions during the setup and the preparation of the paper and to the referees for constructive comments on earlier versions of the paper. Research is supported by the VEGA grant (Slovak Grant Agency) No 1/7295/20  相似文献   

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