首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Assuming that private forecasters learn inflation dynamics to form their inflation expectations and that they believe a hybrid New Keynesian Phillips curve (NKPC) to capture the true data‐generating process of inflation, we aim at establishing the role of backward‐ and forward‐looking information in the inflation expectation formation process. We find that longer term expectations are crucial in shaping shorter horizon expectations. While the influence of backward‐looking information seems to diminish over time, we do not find evidence of a structural break in the expectation formation process of professional forecasters. Our results further suggest that the weight put on longer term expectations does not solely reflect a mean‐reverting process to trend inflation. Rather, it might also capture beliefs about the central bank's long‐run inflation target and its credibility to achieve inflation stabilization.  相似文献   

2.
Prior studies use a linear adaptive expectations model to describe how analysts revise their forecasts of future earnings in response to current forecast errors. However, research shows that extreme forecast errors are less likely than small forecast errors to persist in future years. If analysts recognize this property, their marginal forecast revisions should decrease with the forecast error's magnitude. Therefore, a linear model is likely to be unsatisfactory at describing analysts' forecast revisions. We find that a non‐linear model better describes the relation between analysts' forecast revisions and their forecast errors, and provides a richer theoretical framework for explaining analysts' forecasting behaviour. Our results are consistent with analysts' recognizing the permanent and temporary nature of forecast errors of differing magnitudes. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

3.
In this article we model the log of the US inflation rate by means of fractionally integrated processes. We use the tests of Robinson (1994) for testing this type of hypothesis, which include, as particular cases, the I(0) and I(1) specifications, and which also, unusually, have standard null and local limit distributions. A model selection criterion is established to determine which may be the best model specification of the series, and the forecasting properties of the selected models are also examined. The results vary substantially depending on how we specify the disturbances. Thus, if they are white noise, the series is I(d) with d fluctuating around 0.25; however, imposing autoregressive disturbances, the log of the US inflation rate seems to be anti‐persistent, with an order of integration smaller than zero. Looking at the forecasting properties, those models based on autocorrelated disturbances (with d < 0) predict better over a short horizon, while those based on white noise disturbances (with d > 0) seem to predict better over longer periods of time. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

4.
This paper shows how to extract the density of information shocks from revisions of the Bank of England's inflation density forecasts. An information shock is defined in this paper as a random variable that contains the set of information made available between two consecutive forecasting exercises and that has been incorporated into a revised forecast for a fixed point event. Studying the moments of these information shocks can be useful in understanding how the Bank has changed its assessment of risks surrounding inflation in the light of new information, and how it has modified its forecasts accordingly. The variance of the information shock is interpreted in this paper as a new measure of ex ante inflation uncertainty that measures the uncertainty that the Bank anticipates information perceived in a particular quarter will pose on inflation. A measure of information absorption that indicates the approximate proportion of the information content in a revised forecast that is attributable to information made available since the last forecast release is also proposed.  相似文献   

5.
This paper examines the problem of forecasting macro‐variables which are observed monthly (or quarterly) and result from geographical and sectorial aggregation. The aim is to formulate a methodology whereby all relevant information gathered in this context could provide more accurate forecasts, be frequently updated, and include a disaggregated explanation as useful information for decision‐making. The appropriate treatment of the resulting disaggregated data set requires vector modelling, which captures the long‐run restrictions between the different time series and the short‐term correlations existing between their stationary transformations. Frequently, due to a lack of degrees of freedom, the vector model must be restricted to a block‐diagonal vector model. This methodology is applied in this paper to inflation in the euro area, and shows that disaggregated models with cointegration restrictions improve accuracy in forecasting aggregate macro‐variables. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

6.
The paper considers the use of information by a panel of expert industry forecasters, focusing on their information-processing biases. The panel forecasts construction output by sector up to three years ahead. It is found that the biases observed in laboratory experiments, particularly ‘anchoring’, are observable. The expectations are formed by adjusting the previous forecast to take new information into account. By analysing forecast errors it is concluded that the panel overweight recently released information and do not understand the dynamics of the industry. However, their forecasts, both short and long term, are better than an alternative econometric model, and combining the two sources of forecasts leads to a deterioration in forecast accuracy. The expert forecasts can be ‘de-biased’, and this leads to the conclusion that it is better to optimally process information sources than to combine (optimally) alternative forecasts.  相似文献   

7.
In order to provide short‐run forecasts of headline and core HICP inflation for France, we assess the forecasting performance of a large set of economic indicators, individually and jointly, as well as using dynamic factor models. We run out‐of‐sample forecasts implementing the Stock and Watson (1999) methodology. We find that, according to usual statistical criteria, the combination of several indicators—in particular those derived from surveys—provides better results than factor models, even after pre‐selection of the variables included in the panel. However, factors included in VAR models exhibit more stable forecasting performance over time. Results for the HICP excluding unprocessed food and energy are very encouraging. Moreover, we show that the aggregation of forecasts on subcomponents exhibits the best performance for projecting total inflation and that it is robust to data snooping. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

8.
Combinations of several forecasts are now quite commonly used as inputs into business planning models. For example, capital budgeting generally involves a synthesis of several sources of economic forecasts. In such cases, where uncertainty and risk are also being explicitly considered, the statistical specification of the combined forecasts becomes particularly important. An investigation of the monthly forecasts of annual inflation from nine leading U.K. economic models was undertaken to examine the circumstances under which well-specified and efficient combined forecasts could be produced. This has helped to refine the general guidelines for the practical use of combinations in planning models.  相似文献   

9.
In the light of the still topical nature of ‘bananas and petrol’ being blamed for driving much of the inflationary pressures in Australia in recent times, the ‘headline’ and ‘underlying’ rates of inflation are scrutinised in terms of forecasting accuracy. A general structural time‐series modelling strategy is applied to estimate models for alternative types of Consumer Price Index (CPI) measures. From this, out‐of‐sample forecasts are generated from the various models. The underlying forecasts are subsequently adjusted to facilitate comparison. The Ashley, Granger and Schmalensee (1980) test is then performed to determine whether there is a statistically significant difference between the root mean square errors of the models. The results lend weight to the recent findings of Song (2005) that forecasting models using underlying rates are not systematically inferior to those based on the headline rate. In fact, strong evidence is found that underlying measures produce superior forecasts. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
This paper presents a comparative analysis of the sources of error in forecasts for the UK economy published over a recent four-year period by four independent groups. This analysis rests on the archiving at the ESRC Macroeconomic Modelling Bureau of the original forecasts together with all their accompanying assumptions and adjustments. A method of decomposing observed forecast errors so as to distinguish the contributions of forecaster and model is set out; the impact of future expectations treated in a ‘model-consistent’ or ‘rational’ manner is specifically considered. The results show that the forecaster's adjustments make a substantial contribution to forecast performance, a good part of which comes from adjustments that bring the model on track at the start of the forecast period. The published ex-ante forecasts are usually superior to pure model-based ex-post forecasts, whose performance indicates some misspecification of the underlying models.  相似文献   

11.
星形胶质细胞是神经胶质细胞的主要组成部分,遍布整个神经系统.以往认为星形胶质细胞的功能主要为支持营养神经元,参与物质代谢,血脑屏障形成等等,但最近研究发现它们还可促进突触形成,影响信号传导及突触可塑性,从而在学习记忆的形成中发挥重要作用.  相似文献   

12.
This article addresses the problem of forecasting time series that are subject to level shifts. Processes with level shifts possess a nonlinear dependence structure. Using the stochastic permanent breaks (STOPBREAK) model, I model this nonlinearity in a direct and flexible way that avoids imposing a discrete regime structure. I apply this model to the rate of price inflation in the United States, which I show is subject to level shifts. These shifts significantly affect the accuracy of out‐of‐sample forecasts, causing models that assume covariance stationarity to be substantially biased. Models that do not assume covariance stationarity, such as the random walk, are unbiased but lack precision in periods without shifts. I show that the STOPBREAK model outperforms several alternative models in an out‐of‐sample inflation forecasting experiment. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

13.
Telomeres carry out conserved and possibly ancient functions in meiosis. During the specialized prophase of meiosis I, meiotic prophase, telomeres cluster on the nuclear envelope and move the diploid genetic material around within the nucleus so that homologous chromosomes can align two by two and efficiently recombine with precision. This recombination is in turn required for proper segregation of the homologs into viable haploid daughter cells. The meiosis-specific telomere clustering on the nuclear envelope defines the bouquet stage, so named for its resemblance to the stems from a bouquet of cut flowers. Here, a comparative analysis of the literature on meiotic telomeres from a variety of different species illustrates that the bouquet is nearly universal among life cycles with sexual reproduction. The bouquet has been well documented for over 100 years, but our understanding of how it forms and how it functions has only recently begun to increase. Early and recent observations document the timing and provide clues about the functional significance of these striking telomere movements.  相似文献   

14.
Comparative genome analyses reveal that most functional domains of human genes have homologs in widely divergent species. These shared functional domains, however, are differentially shuffled among evolutionary lineages to produce an increasing number of domain architectures. Combined with duplication and adaptive evolution, domain shuffling is responsible for the great phenotypic complexity of higher eukaryotes. Although the domain-shuffling hypothesis is generally accepted, determining the molecular mechanisms that lead to domain shuffling and novel gene creation has been challenging, as sequence features accompanying the formation of known genes have been obscured by accumulated mutations. The growing availability of genome sequences and EST databases allows us to study the characteristics of newly emerged genes. Here we review recent genome-wide DNA and EST analyses, and discuss the three major molecular mechanisms of gene formation: (1) atypical spicing, both within and between genes, followed by adaptation, (2) tandem and interspersed segmental duplications, and (3) retrotransposition events. Received 18 October 2006; received after revision 18 November 2006; accepted 28 November 2006  相似文献   

15.
Summary Immotile apyrene spermatozoa of the silkworm have a thick electron-dense flagellar membrane. On activation of apyrene spermatozoa by initiatorin, a prostatic endopeptidase of the silkworm, or by trypsin, the flagellar membrane becomes thinner, with the formation of many micropores. It then resembles that of motile apyrene spermatozoa in vivo.  相似文献   

16.
The difficulty in modelling inflation and the significance in discovering the underlying data‐generating process of inflation is expressed in an extensive literature regarding inflation forecasting. In this paper we evaluate nonlinear machine learning and econometric methodologies in forecasting US inflation based on autoregressive and structural models of the term structure. We employ two nonlinear methodologies: the econometric least absolute shrinkage and selection operator (LASSO) and the machine‐learning support vector regression (SVR) method. The SVR has never been used before in inflation forecasting considering the term spread as a regressor. In doing so, we use a long monthly dataset spanning the period 1871:1–2015:3 that covers the entire history of inflation in the US economy. For comparison purposes we also use ordinary least squares regression models as a benchmark. In order to evaluate the contribution of the term spread in inflation forecasting in different time periods, we measure the out‐of‐sample forecasting performance of all models using rolling window regressions. Considering various forecasting horizons, the empirical evidence suggests that the structural models do not outperform the autoregressive ones, regardless of the model's method. Thus we conclude that the term spread models are not more accurate than autoregressive models in inflation forecasting. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

17.
Assembly of functional major histocompatibility complex (MHC) class I peptide complexes within the endoplasmic reticulum is critically important for the development of an adaptive immune response. The highly regulated loading of peptides onto MHC class I molecules is controlled by a multi-component chaperone system called the MHC class I peptide loading complex. The recent identification of the thioredoxin family member ERp57 as a component of the loading complex led to an interesting question: Why is there a thiol-disulfide oxidoreductase inside a complex dedicated to inserting peptides into a receptor binding site? Most recently, specific ERp57-mediated disulfide bond rearrangements have been identified inside the loading complex. What these biochemical events mean for the peptide loading process remains a matter of conjecture. While several important questions wait to be answered, this review intends to summarize our current view of the oxidative folding of MHC class I molecules and addresses the question of how the receptor ligand interaction might be regulated by thiol-based redox reactions.  相似文献   

18.
The main focus of this paper is to model the daily series of banknotes in circulation. The series of banknotes in circulation displays very marked seasonal patterns. To the best of our knowledge the empirical performance of two competing approaches to model seasonality in daily time series, namely the ARIMA‐based approach and the Structural Time Series approach, has never been put to the test. The application presented in this paper provides valid intuition on the merits of each approach. The forecasting performance of the models is also assessed in the context of their impact on the liquidity management of the Eurosystem. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

19.
Summary Applying a new silver staining technique it could be shown that in very early spermatids strong argyrophilia in nucleoli is confined to their granular and fibrillar components; fibrillar centers are devoid of silver. During subsequent developmental stages remnants of these nucleolar components are present in the form of intensively silver stained clusters of coiled fibers. As chromatin condensation proceeds, these fibrous structures decrease in size and density and are finally completely absent. The nucleus of the mature sperm contains only the space in which they formerly existed, now silver negative, as the so-called nuclear vacuole.Acknowledgment. This investigation was supported partly by grant from the Universitätspreis der Wiener Wirtschaft.  相似文献   

20.
Summary In the European corn borer, subtle changes in imaginal wing discs during diapause constitute observable indications of diapause development, in experimental as well as in field-grown larvae. Wing disc diapause development is dependent mainly on temperature, and its total achievement is a necessary condition for good diapause termination. By applying these observations, we have improved a method that provides homogeneous populations of larvae that can resume their development rapidly in any season.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号