Dynamic spillovers of oil price shocks and economic policy uncertainty

This study examines the dynamic relationship between changes in oil prices and the economic policy uncertainty index for a sample of both net oil-exporting and net oil-importing countries over the period 1997:01–2013:06. To achieve that, an extension of the Diebold and Yilmaz (2009, 2012) dynamic spillover index based on structural decomposition is employed. The results reveal that economic policy uncertainty (oil price shocks) responds negatively to aggregate demand oil price shocks (economic policy uncertainty shocks). Furthermore, during the Great Recession of 2007–2009, total spillovers increase considerably, reaching unprecedented heights. Moreover, in net terms, economic policy uncertainty becomes the dominant transmitter of shocks between 1997 and 2009, while in the post-2009 period there is a significant role for supply-side and oil specific demand shocks, as net transmitters of spillover effects. These results are important for policy makers, as well as, investors interested in the oil market

Dynamic co-movements of stock market returns, implied volatility and policy uncertainty

We examine time-varying correlations among stock market returns, implied volatility and policy uncertainty. Our findings suggest that correlations are indeed time-varying and sensitive to oil demand shocks and US recessions. Highlights: We examine dynamic correlations of stock market returns, implied volatility and policy uncertainty. Dynamic correlations reveal heterogeneous patterns during US recessions. Aggregate demand oil price shocks and US recessions affect dynamic correlations. A rise in the volatility of policy uncertainty dampens stock market returns and increases uncertainty. Increases in stock market volatility reduce stock market returns and increase uncertainty

Coplanar waveguide discontinuities for P-I-N diode switches and filter applications

A full wave space domain integral equation (SDIE) analysis of coplanar waveguide (CPW) two port discontinuities is presented. An experimental setup to measure the S-parameters of such discontinuities is described. Experimental and theoretical results for CPW realizations of pass-band and stop-band filters are presented. The S-parameters of such structures are plotted in the frequency range 5 to 25 GHz

Neuronal Distortions of Reward Probability without Choice

Reward probability crucially determines the value of outcomes. A basic phenomenon, defying explanation by traditional decision theories, is that people often overweigh small and underweigh large probabilities in choices under uncertainty. However, the neuronal basis of such reward probability distortions and their position in the decision process are largely unknown. We assessed individual probability distortions with behavioral pleasantness ratings and brain imaging in the absence of choice. Dorsolateral frontal cortex regions showed experience dependent overweighting of small, and underweighting of large, probabilities whereas ventral frontal regions showed the opposite pattern. These results demonstrate distorted neuronal coding of reward probabilities in the absence of choice, stress the importance of experience with probabilistic outcomes and contrast with linear probability coding in the striatum. Input of the distorted probability estimations to decision-making mechanisms are likely to contribute to well known inconsistencies in preferences formalized in theories of behavioral economics

Large spin behavior of anomalous dimensions and short-long strings duality

We are considering the semi-classical string soliton solution of Gubser, Klebanov and Polyakov which represents highly excited states on the leading Regge trajectory, with large spin in $AdS_5$. A prescription relates this soliton solution with the corresponding field theory operators with many covariant derivatives, whose anomalous scaling dimension grows logarithmically with the space-time spin. We explicitly derive the dependence of anomalous dimension on spin for all leading and next-to-leading orders at strong coupling. We develop an iteration procedure which, in principle, allows to derive all terms in the large spin expansion of the anomalous scaling dimension of twist two operators. Our string theory results are consistent with the conjectured "reciprocity" relation, which has been verified to hold in perturbation theory up to five loops in N=4 SYM. We also derive a duality relation between long and short strings.Comment: 15 pages, 1 figure, comments and references adde

Oil shocks and stock markets: Dynamic connectedness under the prism of recent geopolitical and economic unrest.

In this study we examine the dynamic structural relationship between oil price shocks and stock market returns or volatility for a sample of both net oil–exporting and net oil–importing countries between 1995:09 and 2013:07. We accomplish that, by extending the Diebold and Yilmaz (2014) dynamic connectedness measure using structural forecast error variance de- composition. The results for both stock market returns and volatility suggest that connect- edness varies across different time periods, and that this time–varying character is aligned with certain developments that take place in the global economy. In particular, aggregate demand shocks appear to act as the main transmitters of shocks to stock markets during periods characterised by economic–driven events, while supply–side and oil–specific demand shocks during periods of geopolitical unrest. Furthermore, differences regarding the direc- tions and the strength of connectedness can be reported both between and within the net oil–importing and net oil–exporting countries. These results are of particular importance to investors and portfolio managers, given the recent financialisation of the oil market

The XMM-Newton Iron Line Profile of NGC 3783

We report on observations of the iron K line in the nearby Seyfert 1 galaxy, NGC 3783, obtained in a long, 2 orbit (240 ks) XMM-Newton observation. The line profile obtained exhibits two strong narrow peaks at 6.4 keV and at 7.0 keV, with measured line equivalent widths of 120 and 35 eV respectively. The 6.4 keV emission is the K-alpha line from near neutral Fe, whilst the 7.0 keV feature probably originates from a blend of the neutral Fe K-beta line and the H-like line of Fe at 6.97 keV. The relatively narrow velocity width of the K-alpha line (<5000 km/s), its lack of response to the continuum emission on short timescales and the detection of a neutral Compton reflection component are all consistent with a distant origin in Compton-thick matter such as the putative molecular torus. A strong absorption line from highly ionized iron (at 6.67 keV) is detected in the time-averaged iron line profile, whilst the depth of the feature appears to vary with time, being strongest when the continuum flux is higher. The iron absorption line probably arises from the highest ionization component of the known warm absorber in NGC 3783, with an ionization of logxi=3 and column density of 5x10^{22}cm{-2} and may originate from within 0.1pc of the nucleus. A weak red-wing to the iron K line profile is also detected below 6.4 keV. However when the effect of the highly ionized warm absorber on the underlying continuum is taken into account, the requirement for a relativistic iron line component from the inner disk is reduced.Comment: 34 pages, including 11 figures. Accepted for publication in Ap

X-ray Signatures of an Ionized Reprocessor in the Seyfert galaxy Ton S 180

We discuss the hard X-ray properties of the Seyfert galaxy Ton S 180, based upon the analysis of ASCA data. We find the X-ray flux varied by a factor ~2 on a time scale of a few thousand seconds. The source showed significantly higher amplitude of variability in the 0.5-2 keV band than in the 2-10 keV band. The continuum is adequately parameterized as a Gamma ~ 2.5 power-law across the 0.6--10 keV band . We confirm the recent discovery of an emission line of high equivalent width, due to Fe K-shell emission from highly-ionized material. These ASCA data show the Fe line profile to be broad and asymmetric and tentatively suggest it is stronger during the X-ray flares, consistent with an origin from the inner parts of an accretion disk. The X-ray spectrum is complex below 2 keV, possibly due to emission from a blend of soft X-ray lines, which would support the existence of an ionized reprocessor, most likely due to a relatively high accretion rate in this source.Comment: 24 pages, 8 figures. LaTeX with encapsulated postscript. To appear in the Astrophysical Journa