Certyfikat jakości 
kształcenia dla WNE

EBCL
WNE Centrum
Egzaminacyjnym EBC*L 

WP(13)23. High-Frequency and Model-Free Volatility Estimators

Abstrakt

This paper focuses on volatility of financial markets, which is one of the most important issues in finance, especially with regard to modeling high-frequency data. Risk management, asset pricing and option valuation techniques are the areas where the concept of volatility estimators (consistent, unbiased and the most efficient) is of crucial concern. Our intention was to find the best estimator of true volatility taking into account the latest investigations in finance literature. Basing on the methodology presented in Parkinson (1980), Garman and Klass (1980), Rogers and Satchell (1991), Yang and Zhang (2000), Andersen et al. (1997, 1998, 1999a, 199b), Hansen and Lunde (2005, 2006b) and Martens (2007), we computed the various model-free volatility estimators and compared them with classical volatility estimator, most often used in financial models. In order to reveal the information set hidden in high-frequency data, we utilized the concept of realized volatility and realized range. Calculating our estimator, we carefully focused on - (the interval used in calculation), n (the memory of the process) and q (scaling factor for scaled estimators). Our results revealed that the appropriate selection of - and n plays a crucial role when we try to answer the question concerning the estimator efficiency, as well as its accuracy. Having nine estimators of volatility, we found that for optimal n (measured in days) and - (in minutes) we obtain the most efficient estimator. Our findings confirmed that the best estimator should include information contained not only in closing prices but in the price range as well (range estimators). What is more important, we focused on the properties of the formula itself, independently of the interval used, comparing the estimator with the same, n and q parameter. We observed that the formula of volatility estimator is not as important as the process of selection of the optimal parameter n or. Finally, we focused on the asymmetry between market turmoil and adjustments of volatility. Next, we put stress on the implications of our results for well-known financial models which utilize classical volatility estimator as the main input variable.
Robert Ślepaczuk Grzegorz Zakrzewski

WP(12)22. Access to Credit, Factor Allocation and Farm Productivity: Evidence From the CEE Transition Economies

Abstrakt

This paper analyses how farm access to credit affects farm input allocation and farm efficiency in the CEE transition countries. Drawing on a unique farm level panel data with 37,409 observations and employing a matching estimator we are able to control for the key source of endogeneity - unoberserved heterogeneity. We find that farms are credit constrained both in the short-run as well as in the long-run, but that credit constraint is asymmetric between inputs. Our estimates suggest that farm access to credit increases TFP up to 1.9% per 1000 EUR of additional credit. The use of variable inputs and capital investment increases up to 2.3% and 29%, respectively, per 1000 EUR of additional credit. Due to credit-financed investment in labour-saving farm equipment, labour use reduces for low level of credit. Farms are found not to be credit constrained with respect to land.
Jan Fałkowski Pavel Ciaian, d'Artis Kancs

WP(11)21. Emerging versus developed volatility indices. The comparison of VIW20 and VIX indices.

Abstrakt

Modeling of financial markets volatility is one of the most significant issues of contemporary finance, especially with regard to analyzing high-frequency data. Accurate quantification and forecast of volatility are of immense importance in risk management (VaR models, stress testing and worst-case scenario), models of capital market and options valuation techniques. What we show in this paper is the methodology for calculating volatility index for Polish capital market (VIW20 - index anticipating expected volatility of WIG20 index). The methods presented are based on VIX index (VIX White Paper, 2003) and enriched with necessary modifications corresponding to the character of Polish options market. Quoted on CBOE, VIX index is currently known as the best measure of capital investment risk perfectly illustrating the level of fear and emotions of market participants. The conception of volatility index is based on the combination of realized volatility and implied volatility which, using methodology of Derman et al. (1999) and reconstructing volatility surface, reflects both volatility smile as well as its term structure. The research is carried out using high-frequency data (i.e. tick data) for index options on WIG20 index for the period November 2003 - May 2007, in other words, starting with the introduction of options by Warsaw Stock Exchange. All additional simulations are carried out using data gathered in years 1998-2008. Having analyzed VIW20 index in detail, we observed its characteristic behavior during the periods of strong market turmoils. What we also present is the analysis of the influence of VIW20 and VIX index-based instruments both on construction of minimum risk portfolio and on the quality of derivatives portfolio management in which volatility risk and liquidity risk play a key role. The main objective of this paper is to provide foundations for introducing appropriate volatility indices and volatility-based derivatives. This is done with paying attention to crucial methodology changes, necessary if one considers strong markets inefficiencies in emerging countries. As the introduction of appropriate instruments will enable active management of risks that are unhedgable nowadays it will significantly contribute to the development of the given markets in the course of time. In the summary we additionally point to the benefits Warsaw Stock Exchange might obtain from, being one of the few emerging markets possessing appropriately quantified investment risk as well as derivatives to manage it.
Robert Ślepaczuk Grzegorz Zakrzewski

WP(10)20. (In)Efficiency of Matching - the Case of a Post-transition Economy

Abstrakt

This paper approaches the question of efficiency in job placement using regional data for Polish regions (policy-relevant NUTS 4 level) over the time span of 2000-2008. Using a unique data set we estimate the matching function using stochastic frontier as well as difference-in-difference estimators. We have also combined this unique data set with another unique source of data on the ALMPs coverage, unemployment structure across time and regions as well as the individual capacity of local labour offices. We use these data to explain the exceptional variation in estimated efficiency scores.
Our findings suggest that matching abilities are highly driven by demand fluctuations, while unemployment structure, ALMPs and individual labour office capacities have little explanatory power. Although without individual data it is fairly impossible to provide a reliable counterfactual, we raise some arguments to support the claim of job placement inefficiency by public employment services in Poland.
Tomasz Jeruzalski Joanna Tyrowicz

WP(9)19. Analysis of poverty in Poland in 1997 - 2000 using hazard models

Abstrakt

In this work, the size and character of poverty in Poland was studied based on a panel data from CHER (Consortium of Household Panels for European Socio-Economic Research) database for the years 1997 - 2000. The analyses have shown a low households' dynamic of income in this period. The sum of years spent in poverty as well as different sequences of entry to and exit from poverty suggest a permanence of this phenomenon in the population. During the period studied, the basis for the calculation of the number of years spent in poverty was the rate of exit from and entry to poverty. The calculations were made using a method of analyzing poverty based on hazard models, considering observed and unobserved heterogeneity of individuals in order to 'explain' a chance of exit and return to the sphere of poverty.
Agata Kocia Natalia Nehrebecka

WP(8)18. Labour Market Racial Discrimination in South Africa Revisited

Abstrakt

Discrimination is a significant issue in labour market economics across developed as well as developing countries. In this paper we inquire the actual size of wage discrimination in the Republic of Soutn Africa, accounting for large differences in individual endowments. We apply the Oaxaca-Blinder decomposition as well as propensity score matching to adequately determine the role of discrimination in the wage gaps observed. Although the size of the absolute racial wage gap is enormous, amounting for more than 500%, the actual estimated effect non-attributable to other factors ranges between 45%-55%. This estimator, however, assumes homogenous discrimination across the wage distribution, while data suggest that there are significant educational, sectoral and occupational differentials. To account for these effects, we implement propensity score matching by finding 'statistical twins' of the White population among the Black population, thus we demonstrate how wages differ between these groups in comparable labour market situations. Here too we find that wages for the White are on average approximately 30%, while the effects vary at quartiles of the wage distribution.
Joanna Tyrowicz Maciej Szelewicki

WP(7)17. Shadow Employment In Transition - A Matter of Choice or No Choice?

Abstrakt

Shadow employment may follow from two main labour market failures. In the first, official market labour taxation distortions make it ineffective for some agents to engage in registered employment due to a tax wedge, which makes the revenues from unofficial employment higher than the corresponding official ones (tax evasion hypothesis). The alternative explanation draws to labour market tightness - for workers regular employment may be unattainable, which results in seeking earning opportunities beyond the boundaries of the official labour market (market segmentation hypothesis).
We use a unique data set from a survey on undeclared employment. Using propensity score matching and decomposition techniques we demonstrate that workers of the shadow economy are characterized by slightly higher endowments, while their revenues are considerably lower than among the matched official economy counterparts. Although unobservable heterogeneity is considerable, results are robust and point to social exclusion and the market segmentation hypothesis.
Stanisław Cichocki Joanna Tyrowicz

WP(6)16. Blame No One? Investment Decisions Of The Polish Stock-listed Companies

Abstrakt

 It is often raised that enterprises in transition countries are cursed with credit constraints and insufficient capital. Regardless of whether this belief holds for the whole of the economy, the Agency Theory provides a useful theoretical as well as empirical framework helping to verify the efficiency of investment decisions in the case of companies for which 'objective' future cash-flow valuation is available. The assertion of managerial discretion has been verified empirically for many different countries with the analytical background provided by user cost of capital and Tobin's Q theories. This paper's contribution is the analysis of the Polish stock-listed companies behavior with the particular attention devoted to the corporate governance issues. We find that on average these companies overinvest relative to their opportunities, while this phenomenon is more severe in the case of even partial state ownership.
Joanna Tyrowicz

WP(5)15. Teaching quality and decentralization

Abstrakt

This paper attempts to assess outcomes of school system decentralization in Poland. National examination results are analyzed using the value-added model of teaching quality. Variation in decentralized spending is related to estimates of achievement growth. Exploring exam results for three consecutive student cohorts, we are able to control for hidden characteristics of local governments when estimating their impact on student progress. Preceding the main analysis, the paper provides detailed description of trends in local government school spending and service provision over the last 15 years. The main conclusion is that while there is some evidence that decentralization changed patterns of school expenditure, there is no evidence that expenditures have any systematic impact on teaching quality. There is also no evidence that higher spending translates to more equally distributed outcomes. It seems that the only non-negligible impact local governments could have on student achievement is through provision of preschool facilities. However, evidence presented in the paper suggests that many local governments decided to limit preschool services, especially in poor rural areas. That could importantly increase educational inequalities.
Maciej Jakubowski

WP(4)14. Nonlinear Stochastic Convergence Analysis of Regional Unemployment Rates in Poland

Abstrakt

This paper analyses convergence of unemployment rates in Poland at NUTS4 level by testing nonlinear convergence, applying the modified KSS-CHLL for each pair of territorial units. The results suggest that actually the convergence is a rare phenomenon and occurs only in 1916 cases out of potential over 70 000 combinations. This paper inquires what systematic reasons contribute to this phenomenon.
There are some circumstances under which unemployment convergence should be more expected than in others. These include sharing a higher level territorial authority, experiencing similar labour market hardship or sharing the same structural characteristics. For each of these three criteria we analyse the frequency of the differential nonstationarity within groups (as evidence of convergence) and across groups (as evidence of "catching up").
Joanna Tyrowicz Piotr Wójcik

WP(3)13. When Eastern Labour Markets Enter Western Europe CEECs. Labour Market Institutions upon Euro Zone Accession

Abstrakt

This paper reviews the literature on the labour market institutions in European Union Member States in the context of monetary integration. Traditionally, labour markets are a key concept in the optimal currency area theory, playing the role of the only accommodation mechanism of asymmetric shocks after the monetary unification. There are several theoretical frameworks linking the institutional design of the labour market to the potential effectiveness of monetary policy in the context of currency areas. Many empirical studies addressed these issues too, yielding important policy implications for labour market reforms in the process of monetary unification. However, there seem to be "white spots" in this patchwork, which may actually be particularly useful from the perspective of CEECs upon the accession to the euro zone. We suggest these research directions encompassing labour supply and theoretical frameworks of labour market flexibility benchmarking in the context of monetary integration.
Joanna Tyrowicz

WP(2)12. Is the Impact Really That High? The Effect of FDI in Transition

Abstrakt

Literature is not clear on the effect of FDI on the economic performance in hosting countries. The analysed effects include productivity, propensity to export, access to financial markets, etc. Although foreign subsidiaries usually perform better than the average of the hosting economies, sometimes the selection effect is found to be considerable. The analysed effects In this paper we use a unique dataset based on accounting annual reports to the statistical authorities by all medium and large Polish enterprises over a period 1997-2006. We apply a propensity score matching technique to disentangle the effect of self-selection and FDI entry (treatment). We also distinguish explicitly between foreign ownership and privatisation through a foreign investor.
We find strong support of the view that foreign ownership increases access to financing. Evidence suggests also that although FDI enters more frequently companies who already participate in the international trading networks, 20% of the export intensity may be consistently attributed to the treatment effect. On the other hand, we were not able to confirm large effects on efficiency, nor in the case of rentability, while the size of the effects are different for greenfield and private acquisitions as opposed to privatisation.
Joanna Tyrowicz Jan Hagemejer

WP(1)11. Breeding Ones' Own Subprime Crisis

Abstrakt

In this paper we take a simulation approach towards household budgets survey, analysing the impact of changes in labour market status of household members on the ability of this household to service the mortgage payments. Using the current status as benchmark, we performed simulations using stylised facts about labour market evolutions. Households with mortgage are characterised by higher activity rates and lower unemployment rates than demographically comparable households without a credit. While these are typical preconditions for the credit approval decision, this state of matters may not necessarily persist throughout the entire mortgage service period. Firstly, labour market conditions may worsen in general, comprising the credit takers together with the rest of the population. Alternatively, credit takers may undergo employment experience in the same way as other labour market participants.
Consequently, we performed analyses along two scenarios: (i) households with mortgages will gradually become alike the demographically comparable group in terms of employment performance; and (ii) recognising the fact that debtor households members may exert potentially higher effort in maintaining labour market status we model the effects of general employment outlooks deterioration. We use labour force survey data to obtain the probabilities of changing the individual labour market status, while we resort to propensity score matching techniques to provide adequate benchmark for the changes among creditors with relation to general population.
In the simulations we find the share of creditors losing liquidity with the change in the labour market status and the implied burden to the financial sector stability.
Joanna Tyrowicz Tomasz Daras

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