Has the accuracy of german macroeconomic forecasts improved?

The major focus of this paper is to determine whether the accuracy of German macroeconomic forecasts has improved over time. We examine 1-year-ahead forecasts of real GDP and inflation for 1967 to 2001 made by three major German forecasting groups and the OECD. We examine the accuracy of the forecasts over the entire period and in three sub-periods. We conclude that, with some exceptions, the errors of the German forecasters were similar to those of their US and UK counterparts. While the absolute size of the forecast errors has declined, this is not the case for relative accuracy. A benchmark comparison of these predictions with the ex post forecasts of a macroeconometric model indicates that the quality of the growth forecasts can be improved but that the expected increase in accuracy may not be substantial

Rail-oriented development on urban and regional levels - potentials and impacts, policy measures and processes

The actual trend of spatial diffused and functional segregated settlement structures causes long term growth in traffic volumes. One step to more sustainability is land use development along existing passenger rail infrastructure. It is a clear strategy of the federal state of North Rhine-Westphalia e.g., with specific grants to cities, to develop housing close to rail stations. The focus of the presentation could lead to different surveys, each one including the results, their transferablity and the implication for further policy development. According to additional research and development projects at the Land as well as at the European level, further results could be included. 1. Which potentials and which impacts? Both the potentials and the impacts of a rail-oriented development have been analysed by ILS for the NRW Ministry of Urban Development. For the potentials, there has been a survey among over hundred cities in three regions. The results show a considerable amount of available land for new housing around rail stations, but also a substantial variation between regions and among cities. For the impacts, an other survey was accomplished among 2100 persons from six comparable suburban areas with high motorisation rates. It shows, that there is a significant difference in their modal choice, depending on the rail accessibility, although the difference is lower than it might be expected. 2. Policies measures (What?) and processes (how?) The analysis of some best practices both on the urban and regional levels leads to an identification of key factors for success of policy implementation. This was the goal for an ILS survey for the french Ministry for transport and planning, regarding experiences in North Rhine-Westphalia. Not only the "what?" question, about applicated measures and tools, but the "how?" question too, about processes and governance, were investigated. The case analysis is based on the Land level (NRW integrated policies for housing, planning, transport), on the regional level (housing development close to rail stations in the Region Bonn), and on the agglomeration level (integrated local policy in Münster). For this last case for example, several factors are keys of success for a rail oriented development: the continual elaboration of a global strategical concept (giving priority to a polycentric, balanced urban system, promoting resource-efficient settlements patterns, focusing on public transport infrastructure), a clear cooperation among the city departements, (for example based on working groups about the housing program), and a prospective real estate policy (half of the building land belongs to the city, and is mainly close to rail stations). 3. Further experiences and projects Successful experiences exist in NRW from the revitalisation of a railway line and land use development for housing near the stations ("Haller Willem"). Here also activities of NGO`s are of high relevance. Providing housing near railway stations is only a necessary condition for the usage of public transport; accompanied services could increase the effect. So supplying houses with PT tickets inclusive ("mobile home") or the supply of mobility services offered by housing companies could be helpful. The presentation could present ideas and first experiences.

The Clinton era and the U.S. business cycle : what did change?

The 1990s were the most prosperous decade in U.S. economic history. The paper analyses to which extent this period fits into preceding cyclical experience. This is done by classifying the period 1991-12 to 2000-12 with the help of a 4-phase classification scheme based on multivariate discriminance analysis. It is shown that in relation to the post 1970 experience, the ?fabulous decade? saw considerable shifts of influence between the 19 classifying variables. Most noteworthy are the much reduced influence of M2, Net Exports, and Unemployment on the one side and the increase of Real GNP, inflation, Government Expenditure and of Unit Labor Cost on the other side. This confirms interpretations of the fabulous decade as the result of a forbearing monetary policy made possible by a deficit targeting fiscal policy, low inflation and a productivity jump. However, the era looses some of its uniqueness when it is seen in the entire post WW II cycle history. --U.S. business cycle,4-phase scheme,discriminance analysis,Clinton era

Real-Time analysis and visualization for single-molecule based super-resolution microscopy

Accurate multidimensional localization of isolated fluorescent emitters is a time consuming process in single-molecule based super-resolution microscopy. We demonstrate a functional method for real-time reconstruction with automatic feedback control, without compromising the localization accuracy. Compatible with high frame rates of EM-CCD cameras, it relies on a wavelet segmentation algorithm, together with a mix of CPU/GPU implementation. A combination with Gaussian fitting allows direct access to 3D localization. Automatic feedback control ensures optimal molecule density throughout the acquisition process. With this method, we significantly improve the efficiency and feasibility of localization-based super-resolution microscopy

Deutschland im internationalen Vergleich - einige Fragezeichen

Die Debatte um den „Standort Deutschland“ wird durch immer neue Ergebnisse angeheizt. Was ist von den vorgestellten Befunden zu halten? Professor Ullrich Heilemann weist auf die oft willkürlichen inhaltlichen Verengungen, methodischen Mängel und die defizitäre empirische Basis hin. --

Super-resolution microscopy reveals specific recruitment of HIV-1 envelope proteins to viral assembly sites dependent on the envelope C-terminal tail

The inner structural Gag proteins and the envelope (Env) glycoproteins of human immunodeficiency virus (HIV-1) traffic independently to the plasma membrane, where they assemble the nascent virion. HIV-1 carries a relatively low number of glycoproteins in its membrane, and the mechanism of Env recruitment and virus incorporation is incompletely understood. We employed dual-color super-resolution microscopy visualizing Gag assembly sites and HIV-1 Env proteins in virus-producing and in Env expressing cells. Distinctive HIV-1 Gag assembly sites were readily detected and were associated with Env clusters that always extended beyond the actual Gag assembly site and often showed enrichment at the periphery and surrounding the assembly site. Formation of these Env clusters depended on the presence of other HIV-1 proteins and on the long cytoplasmic tail (CT) of Env. CT deletion, a matrix mutation affecting Env incorporation or Env expression in the absence of other HIV-1 proteins led to much smaller Env clusters, which were not enriched at viral assembly sites. These results show that Env is recruited to HIV-1 assembly sites in a CT-dependent manner, while Env(ΔCT) appears to be randomly incorporated. The observed Env accumulation surrounding Gag assemblies, with a lower density on the actual bud, could facilitate viral spread . Keeping Env molecules on the nascent virus low may be important for escape from the humoral immune response, while cell-cell contacts mediated by surrounding Env molecules could promote HIV-1 transmission through the virological synapse

Forecasting with macroeconometric models: A report from the trenches

Econometric models are a widely used and powerful tool in macroeconomic analysis and forecasting. Admittedly, their acceptance by the scientific community has had some hard times during the seventies and eighties: a general decline in the reputation of macroeconomics, the Lucas critique, and failures of the model community to make their often opaque practice transparent had left their marks. Closer looks at the criticism, however, revealed its limited relevance, and the „new/old macroeconomic consensus“ (Blinder, Zarnowitz) of the early 1990s seems to have restored much of the lost credibility. A lack of transparency, however, still diminishes acceptance and credibility of the results, at least within the academic community3. The apparent deficit in model transparency has a number of causes, a major one being the fact that the literature on the practice of macroeconometric forecasting is still sparse (cf. e.g., Klein, Young 1980, pp. 75ff., Adams 1986, pp. 106ff.) and, given the new technical opportunities for model and forecast analysis, it is also somewhat outdated. One explanation for this is that economic deliberations in the model industry back such disregard (Daub 1987, pp. 73ff.) and it may still take some time until the industry realises that transparency is the models' biggest asset. This paper describes in detail the production of a macroeconometric forecast, complementing and enlarging on two earlier papers on the subject (Heilemann 1985, 1990). The model used is the business cycle model of the Rheinisch-Westfälisches Institut für Wirtschaftsforschung (RWI) which has been applied for forecasting since 1978

Has the accuracy of German macroeconomic forecasts improved?

The major focus of this paper is to determine whether the accuracy of German macroeconomic forecasts has improved over time. We examine 1-year-ahead forecasts of real GDP and inflation for 1967 to 2001 made by three major German forecasting groups and the OECD. We examine the accuracy of the forecasts over the entire period and in three sub-periods. We conclude that, with some exceptions, the errors of the German forecasters were similar to those of their US and UK counterparts. While the absolute size of the forecast errors has declined, this is not the case for relative accuracy. A benchmark comparison of these predictions with the ex post forecasts of a macroeconometric model indicates that the quality of the growth forecasts can be improved but that the expected increase in accuracy may not be substantial. --Forecast evaluations,macroeconomic forecasting,accuracy limits