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Abstract

Bayesian VAR (BVAR) models offer a practical solution to the parameter proliferation concerns as they allow to introduce a priori information on seasonality and persistence of inflation in a multivariate framework. We investigate alternative prior specifications in the case of time series with a clear seasonal pattern. In the empirical part we forecast the monthly headline inflation in the Polish economy over the period 2011‒2014 employing two popular BVAR frameworks: a steady-state reduced-form BVAR and just-identified structural BVAR model. To evaluate the forecast performance we use the pseudo real-time vintages of timely information from consumer and financial markets. We compare different models in terms of both point and density forecasts. Using formal testing procedure for density-based scores we provide the empirical evidence of superiority of the steady-state BVAR specifications with tight seasonal priors.

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Authors and Affiliations

Damian Stelmasiak
Grzegorz Szafrański
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Abstract

This article, as far as possible based on the available literature, empirical measurements, and data from mesoscale models describes and compares expected wind conditions within the Baltic Sea area. This article refers to aspects related to the design and assessment of wind farm wind resources, based on the author’s previous experience related to onshore wind energy. The consecutive chapters of this publication are going to describe the present state and the presumptions relating to the development of wind energy within the Baltic Sea area. Subsequently, the potential of the sea was assessed using mesoscale models and empirical data from the Fino 2 mast that is located approximately 200 kilometers away from the majority of areas indicated in the Polish marine spatial development plan draft of Poland for offshore wind farm development (Maritime Office in Gdynia 2018). In the chapter describing mesoscale models, the author focused his attention on the GEOS5.12.4 model as the source of Modern-Era Retrospective Analysis for Research and Application 2 data, also known as MERRA2 (Administration National Aeronautics and Space Agency, 28), which, starting from February 2016, replaced MERRA data (Thogersen et al. 2016) and have gained a wide scope of applications in the assessment of pre-investment and operational productivity due to a remarkable level of correlation with in-situ data. Model-specific data has been obtained for eight locations, which largely overlap with the locations of the currently existing offshore wind farms within the Baltic Sea area. A significant part of this publication is going to be devoted to the description of the previously mentioned Fino 2 mast and to the analysis of data recorded until the end of 2014 by using the said mast (Federal Maritime and Hydrographic Agency 2018). The analysis has been carried out by means using scripts made in the VBA programming language, making it easier to work with large chunks of data. Measurements from the Fino 2 mast, together with long-term mesoscale model-specific measurements can be used, to some extent, for the preliminary assessment of wind farm energy yield in the areas designated for the development of renewable energy in the Polish exclusive maritime economic zone (Maritime Office in Gdynia 2018). In the final part of this article, pieces of information on the forecasted Baltic Sea wind conditions, especially within the exclusive economic zone of Poland, are going to be summarized. A major focus is going to be put on the differences between offshore and onshore wind energy sources, as well as on further aspects, which should be examined in order to optimize the offshore wind power development.

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Authors and Affiliations

Marcin Kostrzewa
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Abstract

The research on default cases of the issuers of Catalyst-listed bonds, encompassing observation period between the years 2011 and 2017, showed that the credit quality of issuers was highly diversified and positively correlated with the size of the issue (the bigger the issue the lower the risk). Catalyst has been an important part of the Polish bond market for several years now, gathering more than 1/3 of the value of all outstanding bond issues. The advantage of trading on organized market such as Catalyst’s includes the presence of specific legal requirements, including market discipline (information obligations), concentration of turnover in one place and the universal availability of quotations (prices, turnover, submitted offers, etc.). The organised market reduces information asymmetries by giving everyone concerned the opportunity to follow price developments, trading and information on the issues and issuers present on the market. Furthermore, regular sessions should provide a higher level of liquidity. In the case of Catalyst, the liquidity level for most listed bonds is still quite low, but some features of organised markets determine the advantages of its existence. From the perspective of funds seekers, especially small ones, the organised market provides better access to the investor base and is often the only chance for them to obtain financing. On the other hand, this segment - i.e. small issuers - is unfortunately the source of the greatest number of problems (defaults and bankruptcies). This picture is not altered by the common practice of offering secured bonds. As we have shown in this article, collaterals of bonds listed on Catalyst can be ineffective for various reasons, especially in the case of issuers who do not cooperate with investors or even deliberately avoid paying off the bonds after defaults. The persistently high share of default rates and the high level of expected loss (EL) in the Gr1 group despite the very favourable economic situation, should lead to an analysis of the admission to trading criteria, exploring the possibility of strengthening the legal protection of bonds as well as the possibility of tightening the subsequent control over the performance of information duties by issuers.

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Authors and Affiliations

Marek Kempny
Przemysław Cichulski
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Abstract

Significant increasing trends in the air temperature were found both in the surface station of Svalbard Lufthavn and in the low-tropospheric temperature field over the Atlantic Arctic. The variability in temperature, as well as the multiannual trend, is at least three times bigger in the winter months than in summer. An attempt was made to explain the high day-to-day variability in the winter air temperature by the daily variability in the regional pressure field and circulation conditions. Six regional-scale circulation patterns were found by applying the principal component analysis to the mean daily sea level pressure (SLP) reanalysis data and their impact on the low-tropospheric air temperature variability was determined. A bipolar pattern, with a positive center over Greenland and a negative center over the White Sea, dominates in the region and strongly influences the air temperature field at 850 hPa geopotential height (correlation coefficients up to –0.65). The second pattern that impacts the temperature field in the Atlantic Arctic is the one with a center of action over Svalbard (mostly a low-pressure center in winter), strongly influencing the air temperature over the Barents Sea. The remaining circulation types, explaining only 5–8% of the total variance of the SLP field each, do not modify significantly the air temperature at 850 hPa geopotential level over the Atlantic Arctic, and none of the circulation types seems to influence the multiannual temperature trends.
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Authors and Affiliations

Ewa Bednorz
1
ORCID: ORCID
Arkadiusz M. Tomczyk
1
ORCID: ORCID
Bartosz Czernecki
1
ORCID: ORCID
Miłosz Piękny
1

  1. Department of Meteorology and Climatology, Institute of Physical Geography and Environmental Planning, Adam Mickiewicz University, B. Krygowskiego 10, 61–680 Poznań, Poland

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