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Pim Ouwehand and Barry Schouten

References Kruskal, W. and F. Mosteller. 1979a. “Representative Sampling I: Non-Scientific Literature.” International Statistical Review 47: 13-24. DOI: http://dx.doi.org/10.2307/1403202. Kruskal, W. and F. Mosteller. 1979b. “Representative Sampling II: Scientific Literature Excluding Statistics.” International Statistical Review 47: 111-123. DOI: http://dx.doi. org/10.2307/1402564. Kruskal, W. and F. Mosteller. 1979c. “Representative Sampling III: Current Statistical Literature.” International Statistical

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Peter Lundquist and Carl-Erik Särndal

. (2009). Representativeness Indicator for Measuring and Enhancing the Composition of Survey Response. RISQ work package 8, deliverable 9. Available at: http://www.risq-project.eu/. (accessed September 19, 2013). Schouten, B., Cobben, F., and Bethlehem, J. (2009). Indicators for the Representativeness of Survey Response. Survey Methodology, 35, 101-113. Schouten, B., Shlomo, N., and Skinner, C. (2011). Indicators for Monitoring and Improving Representativeness of Response. Journal of Official Statistics, 27, 231

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Johannes W.S. Kappelhof

. Cobben. 2007. R-Indexes for the Comparison of Different Fieldwork Strategies and Data Collection Modes. Voorburg/Heerlen: CBS. (Discussion Paper 07002). Available at: http://www.risq-project.eu/papers/schouten-cobben-2007-a.pdf (accessed December 2013). Schouten, B.F. and F. Cobben. 2008. An Empirical Validation of R-Indicators. Voorburg/Heerlen: CBS. (Discussion Paper 08006) Available at: http://www. risq-project.eu/papers/cobben-schouten-2008-a.pdf (accessed December 2013). Schouten,B. F. Cobben, and J. Bethlehem. 2009. “Indicators of Representativeness of Survey

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Dotan Rotem and Gilad Weil

Abstract

The geographic location of Israel and the Palestinian Authorityon the border between Mediterranean and desert climate, and the strong topographic and geomorphological variation resulting from its position on the Great African Rift Valley, combine to sustain a great diversity of landscapes in a very small country. The purpose of this study is to determine whether the protected areas in Israel and the Palestinian Authority adequately represent the range of landscapes and ecosystems in the region.

Altogether, we defined 23 natural ecosystem-units in Israel and the Palestinian Authority, of which 17 are terrestrial landscapes and 6 are aquatic systems. In considering the adequacy of coverage in protected areas, we mapped Israel and the Palestinian Authority landscapes according to a set of environmental factors (climatic, geomorphological, geological and botanical) that we believe most effectively distinguish landscape types in this region. When the separation between adjacent units relies on sharp topographic or edaphic change in the landscape, the mapped units can be separated by a clear and sharp line. When adjacent units are actually a gradient of continuous environmental conditions the separation lines relied mostly on botanic characteristics.

The main land use categories in this analysis were urban areas, agricultural areas, nature reserves, national parks and forest reserves. For the first time in Israel and the Palestinian Authority, we quantified the different landscape types under the different categories of land use. This process, known as systematic conservation planning, allowed us to detect natural landscapes that are underrepresented in protected areas, and can guide decision makers to establish or improve management for the better representation of biodiversity.

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Talita Rosas Ferreira and Luiz Fernando Pires

J., 1972. Dynamics of Fluids in Porous Media. Dover Publications, New York, USA. Bear J. and Cheng A.H-D., 2010. Modeling Groundwater Flow and Contaminant Transport. In: Theory and Applications of Transport in Porous Media, Springer, Heidelberg, Germany. Borges J.A.R. and Pires L.F., 2012. Representative elementary area (REA) in soil bulk density measurements through gamma ray computed tomography. Soil Till. Res., 123, 43-49. Borges J.A.R., Pires L.F., and Pereira A.B., 2012. Computed tomography to estimate the

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Adrian Różański, Dariusz Łydżba and Piotr Jabłoński

References [1] BERAN M.J., Statistical Continuum Theories, Monographs in Statistical Physics, Interscience Publishers, 1968. [2] FELLER W., An Introduction to Probability Theory and its Applications, Vol. I, 2nd Edition, John Wiley and Sons, N.Y., 1961. [3] GITMAN I.M., ASKES H., SLUYS L.J., Representative volume: existence and size determination, Eng. Fract. Mech., Vol. 74, 2007, 2518-2534. [4] GRAHAM S., YANG N., Representative volumes of materials based on microstructural statistics, Scripta

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Volker Bosch

Abstract

Big data will change market research at its core in the long term because consumption of products and media can be logged electronically more and more, making it measurable on a large scale. Unfortunately, big data datasets are rarely representative, even if they are huge. Smart algorithms are needed to achieve high precision and prediction quality for digital and non-representative approaches. Also, big data can only be processed with complex and therefore error-prone software, which leads to measurement errors that need to be corrected. Another challenge is posed by missing but critical variables. The amount of data can indeed be overwhelming, but it often lacks important information. The missing observations can only be filled in by using statistical data imputation. This requires an additional data source with the additional variables, for example a panel. Linear imputation is a statistical procedure that is anything but trivial. It is an instrument to “transport information,” and the higher the observed data correlates with the data to be imputed, the better it works. It makes structures visible even if the depth of the data is limited.

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Xiaoling Liu, Mihai Păunescu, Viorel Proteasa and Jinshan Wu

, or some other kind of average score, be used to represent the set, and under which conditions a comparison based on such measures of central tendency can be reliable? When does the comparison of arithmetic means indicate a grouping of academics, such as a department or a university, performs better than the one it is compared to? In order to answer this question, we proposed a definition of the minimum representative size κ as a parameter which characterizes a pair of data sets which are to be compared. The method is described in details, including the analytical

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Andrzej Leski and Lukasz Obrycki

Representative Load Sequence for the PZL-130 Orlik

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Ł. Rauch, K. Bzowski, D. Bachniak and M. Pietrzyk

modelling – case studies, Computer Methods in Materials Science 8 , 1-10 (2008). [5] L. Rauch, R. Kuziak, M. Pietrzyk, From high accuracy to high efficiency in simulations of processing of dual phase steels, Metallurgical and Materials Transactions A, 2013 (in press) [6] J. Schroeder, D. Balzani, S. Brands, Approximation of random microstructures by periodic statistically similar representative volume elements based on lineal-path functions, Archives of Applied Mechanics 81, 975-997 (2011). [7] S. Brands, J. Schroder, D. Balzani, Statistically similar