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Handling heteroskedasticity in labour demand functions of athletes

Abstract

Based on previous research it can be stated that modelling sport economics related demand curves (e.g. demand for sport events and athletes) is different from other types of modelling. The difference lies in the fact that some parts of the demand curves are nearly horizontal in case of sport goods and nearly vertical in case of athletes, because the price of sport events is inflexible and at the same time, salaries of top athletes are extremely flexible. This study investigates parameter estimation methods appropriate for the relevant demand functions of sport economics. In this cases the generally used ordinary least squares estimator is less robust, so the weighted least squares estimators are able to handle heteroskedasticity. If the distribution of the variables is known, the Newey-West heteroscedasticity corrected estimates give even stronger results. The empirical study analyses footballer transfer fees in top European leagues and identifies a threshold at which the traditional supply-demand functions are not appropriate. According to the results, word class athletes, in a way, can be considered prestige goods for which demand may be irrational.

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Comparison of robust estimators for leveling networks in Monte Carlo simulations

References Hekimoglu, S., & Erenoglu, R. C. (2007). Effect of heteroscedasticity and heterogeneousness on outlier detection for geodetic networks. Journal of Geodesy, 81(2), 137-148. doi:10.1007/s00190-006-0095-z Huber, P. J., & Ronchetti, E. M. (2009). Robust Statistics. John Wiley & Sons, New York Knight, N. L., & Wang, J. (2009). A comparison of outlier detection procedures and robust estimation methods in GPS positioning. Journal of Navigation, 62, 699-709. doi: 10.1017/S0373463309990142 Koch

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THE APPLICATION OF METHODS OF ROBUST M-ESTIMATION IN ESTABLISHING SHIP POSITION IN MARINE TRAFFIC SURVEILLANCE SYSTEMS BASED ON RADAR OBSERVATIONS

ABSTRACT

In the last years considerable emphasis has been placed on safety at sea. There is the maritime security and surveillance system whose main aim is to execute tasks in the interests of maritime safety and to react in case of emergency. They are monitored by networks of radar stations. On such areas we obtain a lot of navigation data which could be used to improve ship’s parameters (position), using know in geodesy modern M-estimation methods. Simultaneous acquisition of navigational information from many independent radar stations will render it possible to obtain a more accurate ship position in marine traffic surveillance systems in relation to the calculated position. A position expected in an adjustment calculus is received from a watch officer. It is burdened with a fallacy of navigation systems and the quality of marking ship’s route on a map. In the case of navigational-parameter measurements used for depicting ship position, one can obtain incorrect results due to a disturbance in the measurement process. In extreme cases, such erroneous data could significantly differ from the anticipated results. Deviating observations could significantly influence the values of measurement results. In order to eliminate the determination of erroneous measurements, one could use resistant estimation methods with suitably selected attenuation functions. The accuracy of a determined position will not be better than the capabilities of the device used. Adjustment gives the possibility of eliminating or minimizing human errors as well as the errors in the indications of navigational devices. This paper presents the latest robust estimation methods using Danish attenuation function for adjustment of navigational observation, using radar observation.

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Application of Square Msplit Estimation in Determination of Vessel Position in Coastal Shipping

References 1. Cellmer S. 2015. Least fourth powers: optimisation method favouring outliers. Survey Review, Vol. 47(345), pp. 411-417. 2. Czaplewski K. 2004. Positioning with Interactive Navigational Structures Implementation, Annual of Navigation, Vol. 7. 3. Ge Y., Yuan Y., Jia N. 2013. More efficient methods among commonly used robust estimation methods for GPS coordinate transformation. Survey Review, Vol. 45(330), pp. 229-234. 4. Guo J., Ou J., Wang H. 2010. Robust estimation for correlated

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Setting M-Estimation Parameters for Detection and Treatment of Influential Values

, and P.A. Smith. 2017 “A Comparison of two Robust Estimation Methods for Business Surveys.” International Statistical Review 85: 270–289. Doi: https://doi.org/10.1111/insr.12177 . Duchesne, P. 1999. “Robust Calibration Estimators.” Survey Methodology 25(1): 43–56. Available at: http://hbanaszak.mjr.uw.edu.pl/TempTxt/Duchesne_1999_RobustCalibrationEstimators.PDF (accessed August 2017). Gwet, J.-P. and L.-P. Rivest. 1992. “Outlier Resistant Alternatives to Ratio Estimator.” Journal of the American Statistical Association 87: 1174–1182. Available at

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Evaluation of Terrestrial Laser Scanner Accuracy in the Control of Hydrotechnical Structures

based on the results of TLS scanning , Annals of Warsaw University of Life Sciences-SGGW Land Reclamation, 2017, 49(1), 29–41. Available: http://ann_landreclam.sggw.pl/z491/art3.pdf [8] M uszyński Z., Application of selected robust estimation methods for calculating vertical displacements of hydrotechnical structures , Studia Geotechnica et Mechanica, 2010, 32(1), 69–80. Available: http://www.sgem.pwr.edu.pl/iss/2010/no1/art05_no1_2010.pdf [9] M uszyński Z., Assessment of suitability of terrestrial laser scanning for determining horizontal

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Research and Development Work Carried out by the Chair of Engineering Geodesy and Measurement and Control Systems, Faculty of Geodesy and Cartography WUT – Thematic Scope and Achievements

’s robust estimation. Reports on geodesy, No. 1 (90), pp. 233-239. Kwaśniak M. (2011b). Effectiveness of chosen robust estimation methods compared to the level of network reliability. Geodesy and Cartography,Vol.60, No1, 2011, pp. 3-19. Kwaśniak M. (2012). Badanie wpływu niezawodności wewnętrznej sieci geodezyjnej na efektywność wybranych podejść do wykrywania błędów grubych. Rozprawa habilitacyjna, Oficyna Wydawnicza Politechniki Warszawskiej, Prace Naukowe: Geodezja, Nr 49. Kwaśniak M. (2015). Identification of the

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