Working Papers

The WNE Working Papers series has been published by the Faculty of Economic Sciences at the University of Warsaw since 2008.

The WNE Working Papers series provides a fast, open channel for disseminating research conducted at the Faculty of Economic Sciences, University of Warsaw. The papers hosted here are working versions (pre-prints) and may evolve as authors refine their analyses, incorporate feedback, or progress through formal peer-review. What you read is the current version released by the authors, timestamped and assigned DOI/ISSN identifiers to ensure precise citation and version tracking. Copyright remains with the authors, who may, at any time, upload a revised file or add a note directing readers to a later, peer-reviewed publication.

The Working Papers series accepts articles by research employees of the Faculty and publications from conferences organised at the Faculty of Economic Sciences at the University of Warsaw. Articles should be original research papers which have not been previously published, on the subject of economics.

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(2) the title page including: the title of the paper, the authors and their affiliation (DOC/DOCX file).

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Number of Results 8

WP(13/2012)79. Small sample properties of matching with caliper

Authors: Strawiński Paweł
A caliper mechanism is a common tool used to prevent from inexact matches. The existing literature discusses asymptotic properties of matching with caliper. In this simulation study we investigate properties in small and medium sized samples. We show…

WP79. Small sample properties of matching with caliper

A caliper mechanism is a common tool used to prevent from inexact matches. The existing literature discusses asymptotic properties of matching with caliper. In this simulation study we investigate properties in small and medium sized samples. We show that caliper causes a significant bias of the ATT estimator and raises its variance in comparison to one-to-one matching.


Strawiński Paweł
propensity score matching caliper Monte Carlo experiment finite sample properties

WP(25/2011)65. Dynamic caliper matching

Authors: Strawiński Paweł
Matched sampling is a methodology used to estimate treatment effects. A caliper mechanism is used to achieve better similarity among matched pairs. We investigate finite sample properties of matching with calipers and propose a slight modification to…

WP65. Dynamic caliper matching

Matched sampling is a methodology used to estimate treatment effects. A caliper mechanism is used to achieve better similarity among matched pairs. We investigate finite sample properties of matching with calipers and propose a slight modification to the existing mechanism. The simulation study compares the performance of both methods and shows that a standard caliper performs well only in case of constant treatment or uniform propensity score distribution. Secondly, in a case of non-uniform distribution or non-uniform treatment the dynamic caliper method outperforms standard caliper matching.


Strawiński Paweł
propensity score matching caliper efficiency Monte Carlo study finite sample properties

WP(5/2011)45. Returns from income strategies in rural Poland

Authors: Fałkowski Jan, Jakubowski Maciej, Strawiński Paweł
 In Poland, rural households are encouraged to diversify their activities both in and outside the agricultural sector in order to stabilize and improve their income. However, relatively few households appear to do this. This paper addresses this…

WP45. Returns from income strategies in rural Poland

 In Poland, rural households are encouraged to diversify their activities both in and outside the agricultural sector in order to stabilize and improve their income. However, relatively few households appear to do this. This paper addresses this issue, investigating the returns from the income strategies of rural households using propensity score matching methods and extensive data sets for 1998-2008. The results suggest that returns from combining farm and off-farm activities are lower than returns from specialization, namely, concentrating on either farming or off-farm activities. The income difference between farmers and those who combine farming and off-farm activities increased after Poland joined the European Union.


Fałkowski Jan, Jakubowski Maciej, Strawiński Paweł
Income diversification rural areas propensity score matching Poland

WP(12/2010)35. Not all that glitters. The direct effects of privatization through foreign investment

Authors: Hagemejer Jan, Tyrowicz Joanna
 Although foreign subsidiaries usually perform better than the average of the hosting economies, empirical literature has also established that the selection effect is statistically significant. In this paper we attempt to evaluate its economic …

WP35. Not all that glitters. The direct effects of privatization through foreign investment

 Although foreign subsidiaries usually perform better than the average of the hosting economies, empirical literature has also established that the selection effect is statistically significant. In this paper we attempt to evaluate its economic relevance, using a unique dataset of annual financial reports by all medium and large Polish enterprises over a period 1996-2007. We match firms privatized with the use of FDI to a control group of non-privatized state owned companies in order to disentangle the effect of self-selection and FDI entry.
Evidence suggests that although FDI enters more frequently into companies who already participate in the international trading networks, roughly half of the export intensity differential may be attributed to the entry of FDI. On the other hand, selection effects seem to dominate as far as efficiency is concerned, while only towards the end of the sample the positive effect of FDI on profitability may be confirmed. 


Hagemejer Jan, Tyrowicz Joanna
privatization transition propensity score matching firm-level analysis Poland

WP(6/2010)29. Latent Variables and Propensity Score Matching

Authors: Jakubowski Maciej
This paper examines how including latent variables can benefit propensity score matching. A researcher can estimate, based on theoretical presumptions, the latent variable from the observed manifest variables and can use this estimate in propensity s…

WP29. Latent Variables and Propensity Score Matching

This paper examines how including latent variables can benefit propensity score matching. A researcher can estimate, based on theoretical presumptions, the latent variable from the observed manifest variables and can use this estimate in propensity score matching. This paper demonstrates the benefits of such an approach and compares it with a method more common in econometrics, where the manifest variables are directly used in matching. We intuit that estimating the propensity score on the manifest variables introduces a measurement error that can be limited when estimating the propensity score on the estimated latent variable. We use Monte Carlo simulations to test how various matching methods behave under distinct circumstances found in practice. Also, we apply this approach to real data. Using the estimated latent variable in the propensity score matching increases the efficiency of treatment effect estimators. The benefits are larger for small samples, for non-linear processes, and for a large number of the manifest variables available, especially if they are highly correlated with the latent variable.


Jakubowski Maciej
factor analysis latent variables propensity score matching

WP(8/2009)18. Labour Market Racial Discrimination in South Africa Revisited

Authors: Szelewicki Maciej, Tyrowicz Joanna
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 in…

WP18. Labour Market Racial Discrimination in South Africa Revisited

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.


Szelewicki Maciej, Tyrowicz Joanna
discrimination Oaxaca-Blinder decomposition propensity score matching Republic of South Africa racial wage gap

WP(7/2009)17. Shadow Employment In Transition - A Matter of Choice or No Choice?

Authors: Cichocki Stanisław, Tyrowicz Joanna
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 unof…

WP17. Shadow Employment In Transition - A Matter of Choice or No Choice?

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.


Cichocki Stanisław, Tyrowicz Joanna
shadow employment propensity score matching Oaxaca-Blinder decomposition transition Poland

WP(2/2009)12. Is the Impact Really That High? The Effect of FDI in Transition

Authors: Hagemejer Jan, Tyrowicz Joanna
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 tha…

WP12. Is the Impact Really That High? The Effect of FDI in Transition

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.


Hagemejer Jan, Tyrowicz Joanna
FDI transition propensity score matching
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