Per Gösta Andersson is Senior Lecturer at the Department of Statistics, Örebro University. He holds a PhD in Mathematical Statistics from Göteborg University. His main research area is statistical inference.

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Lars R. Bergman is Professor in longitudinal research methodology in the behavioral sciences at the Department of Psychology, Stockholm University. He holds a PhD in Psychology and an MA in Statistics, both degrees from Stockholm University. He directs the longitudinal research program Individual Development and Adaptation and his main areas of research are the adjustment process in a life-span perspective and methodological issues in the study of individual development.

Jan F. Bjørnstad is Professor of Statistics and Head of Research at the Division for Statistical Methods and Standards, Statistics Norway. He holds a PhD in Statistics from University of California at Berkeley. His main areas of research are extended likelihood theory, survey sampling and nonresponse issues.

Lennart Bondesson is Professor Emeritus at the Department of Mathematics and Mathematical Statistics, Umeå University. He got his PhD in Mathematical Statistics from Lund University in 1974. His research fields are probability theory, statistical inference, sampling theory, and applied statistics.

Stig Danielsson is Professor Emeritus at the Department of Statistics, Linköping University. He holds a PhD degree in Statistics from Stockholm University. His main research fields are survey methods and traffic statistics.

Gösta Forsman is Chief Statistician, Swedish Road Administration, and Professor Emeritus at the Department of Statistics, Linköping University. He holds a PhD degree in Statistics from Lund University. His main research fields are survey methods and traffic statistics.

Ove Frank is Professor Emeritus at the Department of Statistics, Stockholm University. He holds a PhLic-degree in Mathematical Statistics and a PhD degree in Statistics, both from Stockholm University. His main areas of research include random graphs, network sampling, and statistical network analysis.

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Gebrenegus Ghilagaber** is Associate Professor and Director of Graduate Studies at the Department of Statistics, Stockholm University. He holds a PhD degree in Statistics from Uppsala University and a PhLic degree in Demography from Stockholm University. His main areas of research include survival analysis, multilevel models and demometrics.

Dan Hedlin is Senior Methodologist at the Department of Research & Development, Statistics Sweden, and adjunct Associate Professor at the Department of Statistics, Stockholm University. He holds a PhD in Statistics from University of Southampton. He has research interests in survey methodology and official statistics, including sampling design and estimation, analysis of survey data, statistical editing, response burden as perceived by the respondents themselves and experiments embedded in surveys.

Danutė Krapavickaitė is Associate Professor at the Department of Mathematical Statistics of Vilnius Gediminas Technical University, Senior Researcher at the Institute of Mathematics and Informatics and Chief Statistician at Statistics Lithuania. She holds a PhD degree in Mathematics from Vilnius University. Her main research areas are survey sampling and statistical analysis of data in general.

Seppo Laaksonen is Professor in Statistics at the Department of Social Research of the University of Helsinki, and Head of Research at Statistics Finland. He is also a member of the sampling expert team of the European Social Survey. Seppo’s main research fields are multinational sampling designing, weighting adjustments, imputation methods, analysis of complex survey data, empirical micro labour econometrics, and methods and practices for cross-country comparisons using survey and register data.

Risto Lehtonen is Professor of Statistics at the Department of Social Research, University of Helsinki, and Research Professor, the Social Insurance Institution of Finland. He holds a PhD in Statistics from University of Jyväskylä. His main areas of research are survey sampling, small area estimation and analysis of complex survey data.

Mārtiņš Liberts is a PhD Student at the Faculty of Physics and Mathematics, University of Latvia and Mathematical Statistician at the Central Statistical Bureau of Latvia. He holds a master degree in Mathematics from University of Latvia. He is doing research in survey sampling.

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Boris Lorenc** is Senior Methodologist at the Department of Research & Development, Statistics Sweden. He holds a PhD in Statistics from Stockholm University and degrees in Computer Science, Cognitive Science and Psychology. His research interests are in cognitive aspects of survey data collection, and in nonresponse and mixed-mode issues. His current work activities include applying Enterprise Architecture principles within Statistics Sweden.

Svein Nordbotten is Professor Emeritus in Information Science at University of Bergen. His main research interests are statistical methods in official statistics, system design and implementations of computer and communication technology.

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Aleksandras Plikusas** is Associate Professor at the Department of Mathematical Analysis of the Faculty of Mathematics and Informatics of Vilnius University and Senior Researcher of Institute of Mathematics and Informatics. He holds a PhD degree in Mathematics from Vilnius University. His main research area is survey sampling.

Bo Sundgren is Professor of Informatics at Stockholm University, Department of Computer and Systems Sciences. He has a PhD degree in Information Processing from Stockholm University. His main research interests include information systems, databases, metadata systems, and business models in the information economy.

Carl-Erik Särndal was Professor at Université de Montréal and at Statistics Sweden. He is a co-author of Model Assisted Survey Sampling (Springer-Verlag, 1992), with Bengt Swensson and Jan Wretman.

Imbi Traat** **is Associate Professor at the Institute of Mathematical Statistics, University of Tartu. She holds a PhD from Vilnius University in Physics and Mathematics. Her main areas of research are Survey Sampling theory, multivariate distributions and matrix theory.

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Jan Wretman** is Professor Emeritus at the Department of Statistics, Stockholm University. He holds a PhLic in Statistics from the University of Umeå. His main area of research is survey sampling.

Li-Chun Zhang is Senior Reseacher at Department of IT and Statistical Methods, Statistics Norway. He holds a PhD in Statistics from University of Tromsø. His main research fields include survey sampling, treatment of non-sampling errors, small area estimation, statistical data editing, price index calculations, and statistical theory for register-based statistics.