Portait

I am Assistant Professor at the School of Psychology and Artificial Intelligence at Radboud University Nijmegen and I lead the Computational Cognitive Science (CCS) group at the Donders Institute for Brain, Cognition and Behaviour.

My research interests span the cognitive sciences, including psychology, computer science, philosophy, cognitive neuroscience and AI. I have special interest and expertise in computational complexity theory and its applications in cognitive science.

For more info, check out my Computational Cognitive Science group's page.

[Curriculum vitae]



Recent and upcoming events:

Dagstuhl Seminar on Resource-bounded Problem Solving, Leibniz Center for Informatics, Schloss Dagstuhl, Germany, August 2014.

Tutorial Computational complexity analysis for cognitive scientists, CogSci2013, Berlin, August, 2013.

Symposium on "Constraints on Bayesian explanations", with Johan Kwisthout, David Reichert, Carlos Zednik, and Matteo Colombo, CogSci2013, Berlin, August, 2013. For a (revised) version of the symposium description, see here

Plenary talk at 2nd Conference on Games, Interactive Rationality, and Learning, Department of Philosophy and Cognitive Science, Lund, Sweden, April 23-26, 2013.

A new special issue of the Journal of Problem Solving, with papers inspired by Dagstuhl Seminar on Computer Science & Problem Solving: New Foundations.

Research aims

Portait

Check out my Computational Cognitive Science group's page.

An overarching aim of my research is to advance the theoretical foundations of models and explanations in cognitive science using computability and complexity theory.

For an accessible introduction to my research in Dutch, see here a paper that appeared in the Dutch AI student magazine De Connectie.

Interests

I am particularly interested in the puzzling phenomenon that humans can do apparently intractable cognitive tasks in a blink of an eye, i.e., taking no more than on the order of (milli)seconds.

In contrast, our best models of such tasks postulate computations that take astronomical amounts of time (e.g., NP-hard or otherwise intractable models), such as weeks, months, years or even centuries.

This "intractability phenomenon" is quite common in cognitive science. It is observed in practically all domains of cognition, including perception, language, reasoning, categorization, decision making, and motor planning. It is also not specific to any particular class of models, as it occurs for symbolic, neural network, probabilistic (e.g. Bayesian), dynamical, logicist, and even heuristic models of cognition.

One of my research goals is analyzing the nature and causes of intractability in models of cognition and, in effect, deepening our understanding and explanations of cognition.

Generally, I am interested in the relationship between computational modeling and cognitive explanations, criteria for plausible or `good' explanations, the relationship between different levels of explanation, the relationship between 'why' and 'how' explanations, the interreducability of different models of cognition.

In my applications I focus on context-sensitive forms of cognition, such as prediction, abduction, action understanding, theory of mind, communication, problem solving, and analogy.

Research questions

Questions that I research include the following:

  • What are the computational limits of the human brain? Can cognitive scientists use these limits to make better guesses about how cognition works? Can we mathematically characterize these limits?

  • What makes an explanation computationally plausible or implausible? What makes for `good' explanations of cognition? Are rational or teleological explanations free from computational or mechanistic constraints?

  • How can humans often quickly perform apparently intractable tasks? Can this be explained by their use of heuristics or approximations? How can heuristics maintain consistency between algorithmic- and computational-level explanations? What is approximated by approximate explanations?

  • How can cognitive scientists design models that scale from the lab to the situations of real-world complexity? Is complex cognition a property of the brain, or of a brain-body-world coupling? Are there tasks that are intractable for the brain, but not for embodied and situated agents?

  • My approach to these questions is characterized by the use of conceptual analysis, formal modeling, and computational complexity analysis. Where possible and appropriate, I also use computer simulation and behavioral experimentation.

    Key Publications

    Foundations

    Kwisthout, J. & van Rooij, I. (2013). Bridging the gap between theory and practice of approximate Bayesian inference. Cognitive Systems Research, 24,2-8.

    van Rooij, I. & Wareham, T. (2012). Intractability and approximation of optimization theories of cognition. Journal of Mathematical Psychology, 56,232-247.

    van Rooij, I., Wright, C. & Wareham, H.T. (2012). Intractability and the use of heuristics in psychological explanations. Synthese. 187,471-487. [pdf]

    van Rooij, I. (2012). Self-organization takes time too.Topics in Cognitive Science, 4, 63-71.

    Kwisthout, J., Wareham, T., & van Rooij, I. (2011). Bayesian intractability is not an ailment that approximation can cure. Cognitive Science, 35(5), 779-784. [Published online: pdf]

    van Rooij, I. (2008). The tractable cognition thesis. Cognitive Science, 32, 939-984. [pdf]

    Applications

    Blokpoel, M., Kwisthout, J. & van Rooij, I. (2012). When can predictive brains be truly Bayesian? Frontiers in Theoretical and Philosophical Psychology, 3(460), 1-3.

    van Rooij, I., Kwisthout, J., Blokpoel, M., Szymanik, J., Wareham, T. & Toni, I. (2011). Intentional communication: Computationally easy or difficult? Frontiers in Human Neuroscience, 5(52), 1-18.

    Wareham, H.T., Evans, P. & van Rooij, I. (2011). What does (and doesn't) make analogical problem solving easy? Journal of Problem Solving, 3(2), 30-71.

    Wareham, H.T. & van Rooij, I. (2011). On the computational challenges of analogy-based generalization. Cognitive Systems Research, 12(3-4), 266-280.

    Portait

    Uithol, S., van Rooij, I., Bekkering, H., & Haselager, P. (2011). What do mirror neurons mirror? Philosophical Psychology, iFirst, 1-17. DOI:10.1080/09515089.2011.562604.

    van Dijk, J., Kerkhofs, R., van Rooij, I., & Haselager, P. (2008). Can there be such a thing as embodied embedded cognitive neuroscience? Theory & Psychology, 13(8), 297-316.

    van Rooij, I. & Wareham, T. (2008). Parameterized complexity in cognitive modeling: Foundations, applications and opportunities. Computer Journal, 51(3), 385-404.

    Empirical

    Blokpoel, M., van Kesteren, M., Stolk, A., Haselager, P., Toni, I., & van Rooij, I. (2012). Recipient design in human communication: Simple heuristics or perspective taking? Frontiers in Human Neuroscience,6,1-13.

    Tak, S., Plaisier, M., & van Rooij, I. (2008). Some tours are more equal than others: The convex-hull model revisited with lessons for testing models of the Traveling Salesperson Problem. Journal of Problem Solving, 2, 4-28. [paper in pdf and software & illustrations]

    van Rooij, I., Schactman, A., Kadlec, H., & Stege, U. (2006). Perceptual or analytical processing? Evidence from children’s and adult’s performance on the Euclidean Traveling Salesperson problem. Journal of Problem Solving, 1(1), 44-73.

    van Rooij, I., Stege, U., & Schactman, A. (2003). Convex hull and tour crossings in the Euclidean Traveling Salesperson problem: Implications for human performance studies. Memory & Cognition, 31(2), 215-220.


    Publications

    Journal articles

    van Rooij, I., Wright, C., Kwisthout, J., & Wareham, T. (in press). Rational analysis, intractability, and the prospects of 'as if'-explanations. Synthese.

    Otworowska, M., Kwisthout, J. & van Rooij, I. (2014). Counter-factual mathematics for counterfactual predictive models. Frontiers in Consciousness Research, 5(808). (commentary) [pdf]

    Heil, L., van Pelt, S., Kwisthout, J., van Rooij, I. & Bekkering, H. (2014). Higher-level processes in the formation and application of associations during action understanding. Behavioral and Brain Sciences, 37(2), 202 - 203. (commentary) [pdf]

    Stolk, A., Verhagen, L. Schoffelen, J-M., Oosterveld, R., Blokpoel, M., Hagoort, P., van Rooij, I. & Toni, I. (2013). Neural mechanisms of communicative innovation. Proceedings of the National Academy of Sciences (PNAS), 110(36), 14574-14579.

    Blokpoel, M., Kwisthout, J., van der Weide, T., Wareham, T., & van Rooij, I. (2013). A computational-level explanation of the speed of goal inference. Journal of Mathematical Psychology, 570(3-4), 117-133.

    Kwisthout, J. & van Rooij, I. (2013). Bridging the gap between theory and practice of approximate Bayesian inference. Cognitive Systems Research, 24,2-8.

    Tak, S., P. Westendorp, P., & van Rooij (2013). Being good enough is enough? The use of keyboard shortcuts. Interacting with computers. doi: 10.1093/iwc/iwt016

    van Rooij, I. (2012). Self-organization takes time too.Topics in Cognitive Science, 4, 63-71. [pdf]

    van Rooij, I. & Wareham, T. (2012). Intractability and approximation of optimization theories of cognition. Journal of Mathematical Psychology, 56,232-247.

    van Rooij, I., Wright, C. & Wareham, H.T. (2012). Intractability and the use of heuristics in psychological explanations. Synthese. 187,471-487. [pdf]

    Blokpoel, M., Kwisthout, J. & van Rooij, I. (2012). When can predictive brains be truly Bayesian? Frontiers in Theoretical and Philosophical Psychology, 3(460), 1-3.

    Uithol, S., van Rooij, I., Bekkering, H., & Haselager, P. (2012). Hierarchies in action and motor control. Journal of Cognitive Neuroscience, 24(5), 1077-1086. [pdf]

    Blokpoel, M., van Kesteren, M., Stolk, A., Haselager, P., Toni, I., & van Rooij, I. (2012). Recipient design in human communication: Simple heuristics or perspective taking? Frontiers in Human Neuroscience,6,1-13.

    van Rooij, I., Kwisthout, J., Blokpoel, M., Szymanik, J., Wareham, T. & Toni, I. (2011). Intentional communication: Computationally easy or difficult? Frontiers in Human Neuroscience, 5(52), 1-18. [Published online: pdf]

    Kwisthout, J., Wareham, T., & van Rooij, I. (2011). Bayesian intractability is not an ailment that approximation can cure. Cognitive Science, 35(5), 779-784. [Published online: pdf]

    Paulus, M., Hunnius, S., van Wijngaarden, C., Vrins, S., van Rooij, I. & Bekkering, H. (2011). The role of frequency information and teleological reasoning in infants' and adults' action prediction. Developmental Psychology, 47(4), 976-983.

    Scott, A., Stege, U. & van Rooij, I. (2011). Minesweeper may not be NP-complete but is hard nonetheless. The Mathematical Intelligencer, 33(4), 5-17.

    Wareham, H.T., Evans, P. & van Rooij, I. (2011). What does (and doesn't) make analogical problem solving easy? Journal of Problem Solving, 3(2), 30-71.

    Wareham, H.T. & van Rooij, I. (2011). On the computational challenges of analogy-based generalization. Cognitive Systems Research, 12(3-4), 266-280.

    Uithol, S., van Rooij, I., Bekkering, H., & Haselager, P. (2011). What do mirror neurons mirror? Philosophical Psychology, iFirst, 1-17. DOI:10.1080/09515089.2011.562604.

    Uithol, S., van Rooij, I., Bekkering, H., & Haselager, P. (2011). Understanding motor resonance. Social Neuroscience, 4,1-10.

    Frank, S.L., Haselager, W.F.G., & van Rooij, I. (2009). Connectionist semantic systematicity. Cognition, 110, 358-379. [pdf]

    van Rooij, I. (2008). The tractable cognition thesis. Cognitive Science, 32, 939-984. [pdf]

    van Rooij, I. & Wareham, T. (2008). Parameterized complexity in cognitive modeling: Foundations, applications and opportunities. Computer Journal, 51(3), 385-404. [preprint]

    Tak, S., Plaisier, M., & van Rooij, I. (2008). Some tours are more equal than others: The convex-hull model revisited with lessons for testing models of the Traveling Salesperson Problem. Journal of Problem Solving, 2, 4-28. [paper in pdf and software & illustrations]

    van Dijk, J., Kerkhofs, R., van Rooij, I., & Haselager, P. (2008). Can there be such a thing as embodied embedded cognitive neuroscience? Theory & Psychology, 13(8), 297-316. [prepublication draft in pdf]

    van Rooij, I., Haselager, W.F.G., & Bekkering, H. (2008). Goals are not implied by actions, but inferred from actions and contexts. Behavioral and Brain Sciences, 31, 38-39. (Commentary) [pdf]

    Wareham, T., van Rooij, I., & Müller, M. (2008). Computational complexity analysis can help, but first we need a theory. Behavioral and Brain Sciences, 51(4), 399-400. (Commentary) [prepublication draft in html].

    van Rooij, I., Schactman, A., Kadlec, H., & Stege, U. (2006). Perceptual or analytical processing? Evidence from children’s and adult’s performance on the Euclidean Traveling Salesperson problem. Journal of Problem Solving, 1(1), 44-73. [pdf]

    Keren, G., van Rooij, I., & Schul, Y. (2007). One wrong does not justify another: Accepting dual processes by fallacy of false alternatives. Behavioral and Brain Sciences, 30, 269-270. (Commentary) [prepublication draft in html]

    van Rooij, I., Stege, U., & Kadlec, H. (2005). Sources of complexity in subset choice. Journal of Mathematical Psychology, 49(2), 160-187. [pdf]

    van Rooij, I., Stege, U., & Schactman, A. (2003). Convex hull and tour crossings in the Euclidean Traveling Salesperson problem: Implications for human performance studies. Memory & Cognition, 31(2), 215-220. [pdf]

    Kadlec, H. & van Rooij, I. (2003). Beyond existence: Inferences about mental processes from reversed associations. Cortex, 39(1), 183-187. [prepublication draft in pdf]

    van Rooij, I., Bongers, R. M., & Haselager, W. F. G. (2002). A non-representational approach to imagined action.Cognitive Science, 26(3), 345-375. [pdf]

    Book chapters

    Stolk, A., Blokpoel, M., van Rooij, I., & Toni, I. (in press). On the generation of shared symbols. In R. Willems (Ed.), Cognitive Neuroscience of Natural Language Use. Cambridge University Press.

    Haselager, W.F.G., van Dijk, J., & van Rooij, I. (2008). A lazy brain? Embodied embedded cognition and cognitive neuroscience. In P. Calvo and T. Gomila (Eds.), Handbook of Cognitive Science: An Embodied Approach (pp. 273-290). Oxford: Elsevier.

    Haselager, W. F. G., Bongers, R. M., & van Rooij, I. (2003). Cognitive science, representations and dynamical systems theory. In W. Tschacher and J-P. Dauwalder (Eds.), The dynamical systems approach to cognition (pp. 229- 242). Singapore: World Scientific.

    Refereed conference papers

    Kwisthout, J. & van Rooij, I.(2012). Bridging the gap between theory and practice of approximate Bayesian inference. To appear in the Proceedings for the ICCM2012, April 12-15, Berlin. [pdf]

    Wareham, T., Robere, R., & van Rooij, I. (2012). A change for the better? Assessing the computational cost of re-representation. To appear in the Proceedings for the ICCM2012, April 12-15, Berlin.

    Blokpoel, M., Kwisthout, J., Wareham, T., Haselager, P., Toni, I., & van Rooij, I. (2011). The computational costs of recipient design and intention recognition in communication. In L. Carlson, C. Holscher, & T. Shipley (Eds.), Proceedings of the 33rd Annual Conference of the Cognitive Science Society (pp. 465-470). Austin, TX: Cognitive Science Society. [pdf]

    Wareham, T., Kwisthout, J., Haselager, W., & van Rooij, I. (2011). Ignorance is bliss: A complexity perspective on adapting reactive architectures. Proceedings of the First Joint IEEE International Conference on Development and Learning and on Epigenetic Robotics. [pdf]

    Blokpoel, M., Kwisthout, J., van der Weide, T. & van Rooij, I. (2010). How action understanding can be rational, Bayesian and tractable. In S. Ohlsson & R. Catrambone (Eds.), Proceedings of the 32nd Annual Conference of the Cognitive Science Society (pp. 1643-1648). Austin, TX: Cognitive Science Society. [paper in pdf and supplementary material]

    Müller, M., van Rooij, I., & Wareham, T. (2009). Similarity as tractable transformation. In N. A. Taatgen & H. van Rijn (Eds.), Proceedings of the 31st Annual Conference of the Cognitive Science Society (pp. 50-55). Austin, TX: Cognitive Science Society. [paper in pdf and supplementary material]

    Bieger, J., Sprinkhuizen-Kuyper, I., & van Rooij, I. (2009). Meaningful representations prevent catastrophic interference. Proceedings of the 21st Benelux Conference on Artificial Intelligence (BNAIC 2009)

    Vroon, J., van Rooij, I., & Sprinkhuizen-Kuyper, I. (2009). Matching and Maximizing? A neurally plausible model of stochastic reinforcement learning.Proceedings of the 21st Benelux Conference on Artificial Intelligence (BNAIC 2009)

    van der Meer, S. A., van Rooij, I., & Sprinkhuizen-Kuyper, I. (2008). Evolving fixed-parameter tractable algorithms. In A. Nijholt, M. Pantic, M. Poel, and H. Hondorp (Eds.), Proceedings of BNAIC 2008, the twentieth Belgian-Dutch Artificial Intelligence Conference (pp. 153-160). [pdf]

    van Rooij, I., Evans, P., Müller, M., Gedge, J. & Wareham, T. (2008). Identifying sources of intractability in cognitive models: An illustration using analogical structure mapping. In B. C Love, K. McRae, and V. M. Sloutsky (Eds.), Proceedings of the 30th Annual Conference of the Cognitive Science Society, Austin, TX: Cognitive Science Society (pp. 915-920). [paper in pdf and supplementary material]

    Stege, U., van Rooij, I., Hertel. A, & Hertel P. (2002). An O(pn + 1.151p) algorithm for p-Profit Cover and its practical implications for Vertex Cover. In P. Bose and P. Morin (Eds.), 13th International Symposium on Algorithms and Computation, LNCS 2518 (pp. 249-261). Berlin: Springer-Verlag. [pdf]

    van Rooij, I., Bongers, R. M., & Haselager, W. F. G. (2000). The dynamics of simple prediction: Judging reachability. In L. R. Gleitman & A. K. Joshi (Eds.), Proceedings of the 22nd Annual Conference of the Cognitive Science Society (pp. 535-540). Mahwah, New Jersey: Lawrence Erlbaum Associates. [pdf]

    Book Reviews

    van Rooij, I. (2007). Review of Paul Thagard (2006) “Hot Thought: Mechanisms and Applications of Emotional Coherence”. Philosophical Psychology, 20(5), 659-665. [prepublication draft in pdf]

    van Rooij, I. (2005). Review of Cognition and Technology: Co-existence, convergence and co-evolution, Barbara Gorayska and Jacob L. Mey (Eds.). Pragmatics & Cognition, 13(3), 647–655. [prepublication draft in pdf]

    PhD Thesis

    van Rooij, I. (2003). Tractable cognition: Complexity theory in cognitive psychology. PhD thesis, University of Victoria, Canada. [pdf] [abstract]

    Manuscripts

    Hamilton, M., Müller, M., van Rooij, I., & Wareham, T. (2007). Approximating solution structure. In E. Demaine, G. Z. Gutin, D. Marx, and U. Stege (Eds.), Structure Theory and FPT Algorithmics for Graphs, Digraphs and Hypergraphs. Dagstuhl Seminar Proceedings (Nr. 07281). Internationales Begegnungs- und Forschungszentrum für Informatik (IBFI), Schloss Dagstuhl, Germany. [pdf]

    van Rooij, I. & Wright, C. (2006). The incoherence of heuristically explaining coherence. In R. Sun & N. Miyake (Eds.), Proceedings of 28th Annual Conference of the Cognitive Science Society (p. 2622). [abstract]

    Presentations

    Below appears a selection of representative invited talks. For a complete list of my presentations at conferences, workshops, institutes etc. see my curriculum vitae.

    Selected invited talks

    "Rationality, intractability and the prospects of as-if explanations". Invited talk at the workshop Logic & Cognition at the European Summer School in Logic, Language and Information, 6-17 August, 2012, Opole, Poland.

    "Identifying sources of intractability in models of cognition: Conceptual foundations and applications." Invited talk at Institute of Cognitive Science (IKW), Osnabrück University, Germany, May, 2012.

    "How cognitive scientists are not dealing with intractability (but could be)." Invited talk at University of Amsterdam, Dept. of Psychological Methods, June, 2012. (and invited talk at Groningen University, Institute for Artificial Intelligence, March, 2012)

    "Intractability and the use of heuristics in psychological explanations." Invited talk at Gießener Abendgespräche Kognition und Gehirn, University of Giessen, Germany, October, 2009. (and invited talk at Tilburg University, Philosophy of Mind seminar, Tilburg, November, 2009.

    "What makes a problem hard? A computational perspective," invited talk at Institute for Logical, Language and Computation, University of Amsterdam, Amsterdam, December 2008 (and invited talk at Workshop on Human Problem Solving: New Perspectives, Purdue University, Indiana, USA, November 2008).

    "Dealing with intractability in cognitive modeling: The good, the bad, the impossible and the ugly." Keynote lecture at the European Mathematical Psychology Group 2008, Graz, Austria, September, 2008.

    "When the brain’s computational resources are exhausted: The case for a tractable-design cycle." Invited talk at Department of Psychology at McGill University, Montreal, Canada, March 2006.

    "Wanted: A tractable theory of rationality! Embodiment and embeddedness welcome, but no free lunch included." Good AIfternoon (AI colloquium) at Artificial Intelligence at Radboud University, Nijmegen, May 2005.

    Symposia and workshops

    Workshop "Scaling models of cognition to the real world" at the 11th International Conference on Cognitive Modeling (ICCM2012), April 12, Berlin, Germany.

    Dagstuhl Seminar on "Computer Science & Problem Solving: New Foundations", Aug 28 - Sep 2, 2011, Schloss Dagstuhl, Germany.

    Symposium on "Computational Complexity Analyses of Cognitive Models", 30 July-1 August, 2006, Annual Meeting of the Society for Mathematical Psychology (SMP2006), Vancouver, Canada.

    Courses

    Blackboard

    Teaching

    Computational and formal modeling
    (BKI211: BSc Artificial Intelligence)

    Cognition and Complexity
    (MKI40: MSc Artificial Intelligence, MSc Cognitive Neuroscience)

    Coordination

    Trends in Artificial Intelligence
    (MKI47: MSc Artificial Intelligence)

    Info on Blackboard

    Contact

    Iris van Rooij
    Donders Institute for Brain, Cognition, and Behaviour
    Centre for Cognition
    Radboud University Nijmegen
    Montessorilaan 3
    6525 HR Nijmegen
    The Netherlands

    Tel: +31 (0)24 3612645
    Fax: +31 (0)24 3616066
    Room: Spinozabuilding B.2.32
    Email: email

    The last update to this website was on Thursday 13th of September 2012.