On the usefulness of government spending in the EU area

We investigate the effects of fiscal policy on private consumption and investment in the European Union. A certain consensus has aroused that fiscal impulses have expansionary Keynesian effects on the economic activity. However, the existing empirical literature has concentrated on few countries, mostly outside the EU. We check the validity of this result for the EU area, by using annual data and a panel vector auto-regression approach (PVAR). Our results show that increases in public spending lead to positive and significant effects on private consumption and private investment. According to our baseline estimate, a 1% increase in public spending produces a 0.36% on impact rise in private consumption, and a 0.79% impact rise in private investment. The effects are substantial, and die out slowly (faster in the case of private consumption). A further disaggregation between wage and non-wage components reveals different effects. As for the impact on private consumption, our results show that public salaries have a relatively stronger stimulating role, a result which is probably due to the importance of the public sector especially in continental Europe. On the other hand, the positive impact on private investment is mainly due to the non-wage component of government consumption.

Consumption Multipliers of Different Types of Public Spending: a Structural Vector Error Correction Analysis for the UK

The aim of this paper is to investigate the relationship between government spending and private consumption in the UK, for which there is scarce previous empirical evidence. We disaggregate public expenditure into three categories and search for the corresponding private consumption multipliers. Our analysis includes the estimation of a structural vector error correction (SVEC) model, using quarterly non-interpolated data for the period 1981:1 – 2007:4. Initially, we estimate negative effects on consumption of shocks to total public spending. Then, using the spending decomposition, we find that while shocks to public wages crowd-out private consumption as predicted by neoclassical models, shocks to the non-systematic component of social spending and government purchases of goods and services generate a positive reaction, so to crowd-in private consumption. Thus, the qualitative and quantitative dimensions of fiscal multipliers on private consumption change across different public spending categories. Our findings suggest that any empirical support of competing theoretical models on the issue would benefit from a disaggregation of government expenditure, rather than focusing on the aggregate measure

Fiscal shocks, public debt, and long-term interest rate dynamics

Public finances worldwide have been severely hit by the 2008-2009 Great Recession, stimulating the debate on the consequences of growing fiscal imbalances. Building on Paesani et al. (2006), this paper focuses on the USA, Germany and Italy over the 1983-2009 period and studies the effects of fiscal shocks and government debt accumulation on long-term interest rates, both nationally and across borders. Based on a a theoretical framework, the empirical analysis disentangles permanent and transitory components of interest rates dynamics .nding that sustained debt accumulation leads, at least temporarily, to higher long-term interest rates. The is particularly true for the Italian case. There is also evidence of signi.cant cross-country linkages, mainly between Italy and the USA.

Detection and period measurements of GX1+4 at hard x ray energies with the SIGMA telescope

The galactic Low Mass X ray Binary GX1+4 was detected by the coded aperture hard X ray gamma ray SIGMA telescope during the Feb. to April 1991 observations of the galactic center regions. The source, whose emission varied during the survey of a factor greater than 40 pct., reached a maximum luminosity in the 40 to 140 energy range of 1.03 x 10(exp 37) erg/s (D = 8.5 kpc), thus approaching the emission level of the 1970 to 1980 high state. Two minute flux pulsations were detected on Mar. 22 and on Mar. 31 and Apr. 1. Comparison with the last period measurements shows that the current spin-down phase of GX1+4 is ending. Concerning the proposed association of this source with the galactic center 511 keV annihilation emission, upper limits were derived

Speeding up Simplification of Polygonal Curves using Nested Approximations

We develop a multiresolution approach to the problem of polygonal curve approximation. We show theoretically and experimentally that, if the simplification algorithm A used between any two successive levels of resolution satisfies some conditions, the multiresolution algorithm MR will have a complexity lower than the complexity of A. In particular, we show that if A has a O(N2/K) complexity (the complexity of a reduced search dynamic solution approach), where N and K are respectively the initial and the final number of segments, the complexity of MR is in O(N).We experimentally compare the outcomes of MR with those of the optimal "full search" dynamic programming solution and of classical merge and split approaches. The experimental evaluations confirm the theoretical derivations and show that the proposed approach evaluated on 2D coastal maps either shows a lower complexity or provides polygonal approximations closer to the initial curves.Comment: 12 pages + figure

Radar observation and recontruction of Cosmos 1408 fragmentation

The population of objects in space has increased dramatically over recent decades. Space debris now represents the majority of objects in space resulting from inactive satellites, breakups, collisions and fragmentations. It has become a concern for institutions all over the world and, as such, it has led to the fostering of several programmes to counter the issues. Among these, the use of ground-based sensors for Space Surveillance Tracking (SST) activities and services and tools for analysing fragmentations play a crucial role. This work presents the activities carried out by Politecnico di Milano, Italian Space Agency and Italian National Institute of Astrophysics in this framework, using data from SST networks and the observation measurements from Bistatic Radar for LEo Survey (BIRALES), an Italian bistatic radar belonging to the EUropean Space Surveillance and Tracking (EUSST), which contributed most to the monitoring of the cloud of fragments. Exploiting Two-Line Elements (TLEs) of observed fragments, a reverse engineering approach is used to reconstruct a fragmentation in orbit through the use of the software suite PUZZLE developed at Politecnico di Milano. The analyses focus on studying the fragmentation of the Cosmos 1408 satellite, which occurred on November 15th 2021 following an Anti-SATellite (ASAT) missile test. More than 1000 trackable pieces and millions of smaller debris (estimated from numerical analysis) were produced by this event, increasing the population of inactive objects around the Earth, and threatening nearby orbiting objects. First, the processing method adopted from BIRALES in observing Cosmos debris is presented and discussed and a critical analysis about the derivable information is conducted. Then, these data and those from SST network observations are used to identify the epoch and the location of the fragmentation. In this procedure, the software toolkit PUZZLE, developed by Politecnico di Milano within a project funded by the Italian Space Agency and extended through the European Research Council, is used

The Agile Alert System For Gamma-Ray Transients

In recent years, a new generation of space missions offered great opportunities of discovery in high-energy astrophysics. In this article we focus on the scientific operations of the Gamma-Ray Imaging Detector (GRID) onboard the AGILE space mission. The AGILE-GRID, sensitive in the energy range of 30 MeV-30 GeV, has detected many gamma-ray transients of galactic and extragalactic origins. This work presents the AGILE innovative approach to fast gamma-ray transient detection, which is a challenging task and a crucial part of the AGILE scientific program. The goals are to describe: (1) the AGILE Gamma-Ray Alert System, (2) a new algorithm for blind search identification of transients within a short processing time, (3) the AGILE procedure for gamma-ray transient alert management, and (4) the likelihood of ratio tests that are necessary to evaluate the post-trial statistical significance of the results. Special algorithms and an optimized sequence of tasks are necessary to reach our goal. Data are automatically analyzed at every orbital downlink by an alert pipeline operating on different timescales. As proper flux thresholds are exceeded, alerts are automatically generated and sent as SMS messages to cellular telephones, e-mails, and push notifications of an application for smartphones and tablets. These alerts are crosschecked with the results of two pipelines, and a manual analysis is performed. Being a small scientific-class mission, AGILE is characterized by optimization of both scientific analysis and ground-segment resources. The system is capable of generating alerts within two to three hours of a data downlink, an unprecedented reaction time in gamma-ray astrophysics.Comment: 34 pages, 9 figures, 5 table