This volume constitutes the refereed post-workshop proceedings of two IFIP WG 13.7 workshops on Human-Computer Interaction and Visualization: the 7th HCIV Workshop on Non-formal Modelling for Interaction Design, held at the 29th European Conference on Cognitive Ergonomics, ECCE 2011, in Rostock, Germany, in August 2011 and the 8th HCIV Workshop on HCI and Visualization, held at the 13th IFIP TC 13 Conference on Human-Computer Interaction, INTERACT 2011, in Lisbon, Portugal, in September 2011. The 15 revised papers presented were carefully reviewed and selected for inclusion in this volume. They cover a wide range of topics in the fields of non-formal modeling, visualization and HCI and provide visions from researchers working at or across the borders between these domains that may help develop a holistic cross-discipline.

This book is the final product of a conference organized at the Free Univer- sity, Amsterdam, by some members of the Dutch Human Performance Group and sponsored by the Dutch Psychonomic Society. We first of all thank the Society for financially supporting this publication, and the Free University for providing technical support. P.J.G. Keuss, A.A.J. Mannaerts, and W. Hulstijn, members of the organizing commitee, and J.A. Michon and W. Molenaar collaborated with the editors in defining the fields dealt with at the conference and in the book and in getting together the team of authors. All the chapters in this volume have been reviewed by a team of external referees, who generously spent their time to improve the readability, coher- ence, and scientific standard of the work as a whole: H. Bogers, Institute for Experimental Psychology, University of Groningen, The Netherlands; P. Innocent, Leicester Polytechnic, UK; G.A.M. Kempen, Institute for Cogni- tion Research and Information Technology, Nijmegen, The Netherlands; J. Moraal, Institute for Perception RVO/TNO, Soesterberg, The Netherlands; I.M. van Oorschot, Department of Economics, Free University, Amsterdam, The Netherlands; G.R.E. Ouweneel, Institute for Experimental Psychology, Haren, The Netherlands; J.G.W. Raaymakers, Institute for Perception RVO/TNO, Soesterberg, The Netherlands; G. Rohr, IBM Science Center, Heidelberg, FRG; M.J. Tauber, Department of Computer Science, University of Paderborn, FRG; Y. Waern, Department of Psychology, University of Stockholm, Sweden; G. d'Ydewalle, Department of Psychology, University of Leuven, Belgium.

Engineering Interactive Systems 2007 is an IFIP working conference that brings together researchers and practitioners interested in strengthening the scientific foun- tions of user interface design, examining the relationship between software engine- ing (SE) and human-computer interaction (HCI) and on how user-centerd design (UCD) could be strengthened as an essential part of the software engineering process. Engineering Interactive Systems 2007 was created by merging three conferences: * HCSE 2007 - Human-Centerd Software Engineering held for the first time. The HCSE Working Conference is a multidisciplinary conference entirely dedicated to advancing the basic science and theory of human-centerd software systems engineering. It is organized by IFIP WG 13.2 on Methodologies for User-Centerd Systems Design. * EHCI 2007 - Engineering Human Computer Interaction was held for the tenth time. EHCI aims to investigate the nature, concepts, and construction of user interfaces for software systems. It is organized by IFIP WG 13.4/2.7 on User Interface Engineering. * DSV-IS 2007 - Design, Specification and Verification of Interactive Systems was held for the 13th time. DSV-IS provides a forum where researchers wo- ing on model-based techniques and tools for the design and development of - teractive systems can come together with practitioners and with those working on HCI models and theories.