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NL

prof. dr. L.A. (Andries) van der Ark

Faculty of Social and Behavioural Sciences
Programme group: Methods and statistics
Photographer: Dirk Gillissen

Visiting address
  • Nieuwe Achtergracht 127
  • Room number: D7.13
Postal address
  • Postbus 15776
    1001 NG Amsterdam
  • Expertise

    Research:  My primary interest is the statistical analysis of test data, and within this context my research can be divided into four themes: (1)  finding statistical solutions to practical data problems, such as handling missing data, handling outliers, and item selection; (2)  applications of psychological tests; (3) development of nonparametric item response theory models, including Mokken scale analysis; and (4) the development of categorical marginal models and their application to test data. For all themes, software development (in R) is an important aspect. In addition, I have made methodological and statistical contributions to substantive papers from various areas in the social and behavioral sciences.

     

  • Publications

    2020

    2019

    2018

    • Kuipers, G. S., van Loenhout, Z., van der Ark, L. A., & Bekker, M. H. J. (2018). Is reduction of symptoms in eating disorder patients after 1 year of treatment related to attachment security and mentalization? Eating Disorders: The Journal of Treatment & Prevention, 26(3), 263-269. https://doi.org/10.1080/10640266.2017.1384916 [details]
    • Smits, N., van der Ark, L. A., & Conijn, J. M. (2018). Measurement versus prediction in the construction of patient-reported outcome questionnaires: Can we have our cake and eat it? Quality of Life Research, 7(27), 1673-1682. https://doi.org/10.1007/s11136-017-1720-4 [details]
    • Zijlmans, E. A. O., Tijmstra, J., van der Ark, L. A., & Sijtsma, K. (2018). Item-Score Reliability in Empirical-Data Sets and Its Relationship With Other Item Indices. Educational and Psychological Measurement, 78(6), 998-1020. https://doi.org/10.1177/0013164417728358 [details]
    • Zijlmans, E. A. O., van der Ark, L. A., Tijmstra, J., & Sijtsma, K. (2018). Methods for Estimating Item-Score Reliability. Applied Psychological Measurement, 42(7), 553-570. https://doi.org/10.1177/0146621618758290 [details]
    • de la Torre, J., van der Ark, L. A., & Rossi, G. (2018). Analysis of clinical data from cognitive diagnosis modeling framework. Measurement and Evaluation in Counseling and Development, 51(4), 281-296. https://doi.org/10.1080/07481756.2017.1327286 [details]
    • ten Hove, D., Jorgensen, T. D., & van der Ark, L. A. (2018). On the usefulness of interrater reliability coefficients. In M. Wiberg, S. Culpepper, R. Janssen, J. González, & D. Molenaar (Eds.), Quantitative Psychology: The 82nd Annual Meeting of the Psychometric Society, Zurich, Switzerland, 2017 (pp. 67-75). (Springer Proceedings in Mathematics & Statistics; Vol. 233). Cham: Springer. https://doi.org/10.1007/978-3-319-77249-3_6 [details]
    • van Hemert, F., Jebbink, M., van der Ark, A., Scholer, F., & Berkhout, B. (2018). Euclidean Distance Analysis Enables Nucleotide Skew Analysis in Viral Genomes. Computational and Mathematical Methods in Medicine, 2018, [6490647]. https://doi.org/10.1155/2018/6490647 [details]

    2017

    • Conijn, J. M., van der Ark, L. A., & Spinhoven, P. (2017). Satisficing in mental health care patients: The effect of cognitive symptoms on self-report data quality. Assessment. https://doi.org/10.1177/1073191117714557
    • Koopman, L., Zijlstra, B. J. H., & van der Ark, L. A. (2017). Weighted Guttman errors: Handling ties and two-level data. In L. A. van der Ark, M. Wiberg, S. A. Culpepper, J. A. Douglas, & W-C. Wang (Eds.), Quantitative psychology: The 81st Annual Meeting of the Psychometric Society, Asheville, North Carolina, 2016 (pp. 183-190). (Springer Proceedings in Mathematics & Statistics; Vol. 196). Cham: Springer. https://doi.org/10.1007/978-3-319-56294-0_17 [details]
    • Kuipers, G. S., den Hollander, S., van der Ark, L. A., & Bekker, M. H. J. (2017). Recovery from eating disorder 1 year after start of treatment is related to better mentalization and strong reduction of sensitivity to others. Eating and Weight Disorders, 22(3), 535-547. https://doi.org/10.1007/s40519-017-0405-x [details]
    • Oosterhuis, H. E. M., van der Ark, L. A., & Sijtsma, K. (2017). Standard errors and confidence intervals of norm statistics for educational and psychological tests. Psychometrika, 82(3), 559-588. https://doi.org/10.1007/s11336-016-9535-8 [details]
    • Oosterwijk, P. R., van der Ark, L. A., & Sijtsma, K. (2017). Overestimation of reliability by Guttman’s λ4, λ5, and λ6, and the greatest lower bound. In L. A. van der Ark, M. Wiberg, S. A. Culpepper, J. A. Douglas, & W-C. Wang (Eds.), Quantitative psychology: The 81st Annual Meeting of the Psychometric Society, Asheville, North Carolina, 2016 (pp. 159-172). (Springer Proceedings in Mathematics & Statistics; Vol. 196). Cham: Springer. https://doi.org/10.1007/978-3-319-56294-0_15 [details]
    • Sijtsma, K., & van der Ark, L. A. (2017). A tutorial on how to do a Mokken scale analysis on your test and questionnaire data. British Journal of Mathematical & Statistical Psychology, 70(1), 137-158. https://doi.org/10.1111/bmsp.12078 [details]
    • Sijtsma, K., & van der Ark, L. A. (2017). Reliability. In V. Zeigler-Hill, & T. K. Schackleford (Eds.), Encyclopedia of personality and individual differences (Living ed.). Cham: Springer. https://doi.org/10.1007/978-3-319-28099-8_1348-1, https://doi.org/10.1007/978-3-319-24612-3_1348 [details]

    2016

    • Crisan, D. R., van de Pol, J. E., & van der Ark, L. A. (2016). Scalability coefficients for two-level polytomous item scores: An introduction and an application. In L. A. van der Ark, D. M. Bolt, W-C. Wang, J. A. Douglas, & M. Wiberg (Eds.), Quantitative Psychology Research: The 80th Annual Meeting of the Psychometric Society, Beijing, 2015 (pp. 139-153). (Springer Proceedings in Mathematics & Statistics; Vol. 167). Cham: Springer. https://doi.org/10.1007/978-3-319-38759-8_11 [details]
    • Kuijpers, R. E., van der Ark, L. A., Croon, M. A., & Sijtsma, K. (2016). Bias in Point Estimates and Standard Errors of Mokken’s Scalability Coefficients. Applied Psychological Measurement, 40(5), 331-345. https://doi.org/10.1177/0146621616638500 [details]
    • Kuipers, G. S., van Loenhout, Z., van der Ark, L. A., & Bekker, M. H. J. (2016). Attachment insecurity, mentalization and their relation to symptoms in eating disorder patients. Attachment & Human Development, 18(3), 250-272. https://doi.org/10.1080/14616734.2015.1136660 [details]
    • Oosterhuis, H. E. M., van der Ark, L. A., & Sijtsma, K. (2016). Sample Size Requirements for Traditional and Regression-Based Norms. Assessment, 23(2), 191-202. https://doi.org/10.1177/1073191115580638 [details]
    • Oosterwijk, P. R., van der Ark, L. A., & Sijtsma, K. (2016). Numerical differences between Guttman's reliability coefficients and the GLB. In L. A. van der Ark, D. M. Bolt, W-C. Wang, J. A. Douglas, & M. Wiberg (Eds.), Quantitative Psychology Research: The 80th Annual Meeting of the Psychometric Society, Beijing, 2015 (pp. 155-172). (Springer Proceedings in Mathematics & Statistics; Vol. 167). Cham: Springer. https://doi.org/10.1007/978-3-319-38759-8_12 [details]
    • Straat, J. H., van der Ark, L. A., & Sijtsma, K. (2016). Using Conditional Association to Identify Locally Independent Item Sets. Methodology, 12(4), 117-123. https://doi.org/10.1027/1614-2241/a000115 [details]
    • van der Palm, D. W., van der Ark, L. A., & Vermunt, J. K. (2016). A comparison of incomplete-data methods for categorical data. Statistical Methods in Medical Research, 25(2), 754-774. https://doi.org/10.1177/0962280212465502 [details]
    • van der Palm, D. W., van der Ark, L. A., & Vermunt, J. K. (2016). Divisive Latent Class Modeling as a Density Estimation Method for Categorical Data. Journal of Classification, 33(1), 52-72. https://doi.org/10.1007/s00357-016-9195-5 [details]

    2015

    • Kuijpers, R. E., Bergsma, W. P., van der Ark, L. A., & Croon, M. A. (2015). Comparing estimation methods for categorical marginal models. In R. E. Millsap, D. M. Bolt, L. A. van der Ark, & W-C. Wang (Eds.), Quantitative Psychology Research: The 78th Annual Meeting of the Psychometric Society (pp. 359-375). (Springer Proceedings in Mathematics & Statistics; Vol. 89). Cham: Springer. https://doi.org/10.1007/978-3-319-07503-7_23 [details]
    • Sijtsma, K., & van der Ark, L. A. (2015). Conceptions of reliability revisited and practical recommendations. Nursing research, 64(2), 128-136. https://doi.org/10.1097/NNR.0000000000000077 [details]
    • Sijtsma, K., & van der Ark, L. A. (2015). The many issues in reliability research: Choosing from a horn of plenty. Nursing research, 64(2), 152-154. https://doi.org/10.1097/NNR.0000000000000081 [details]
    • Sijtsma, K., Straat, J. H., & van der Ark, L. A. (2015). Goodness-of-fit methods for nonparametric IRT models. In L. A. van der Ark, D. M. Bolt, W-C. Wang, J. A. Douglas, & S-M. Chow (Eds.), Quantitative Psychology Research: The 79th Annual Meeting of the Psychometric Society, Madison, Wisconsin, 2014 (pp. 109-120). (Springer Proceedings in Mathematics & Statistics; Vol. 140). Cham: Springer. https://doi.org/10.1007/978-3-319-19977-1_9 [details]
    • van Eijnatten, F. M., van der Ark, L. A., & Holloway, S. S. (2015). Ipsative measurement and the analysis of organizational values: an alternative approach for data analysis. Quality and Quantity, 49(2), 559-579. https://doi.org/10.1007/s11135-014-0009-8 [details]
    • van der Ark, L. A., & van Aert, R. C. M. (2015). Comparing confidence intervals for Goodman and Kruskal's gamma coefficient. Journal of Statistical Computation and Simulation, 85(12), 2491-2505. https://doi.org/10.1080/00949655.2014.932791 [details]

    2014

    2013

    • Kuijpers, R. E., van der Ark, L. A., & Croon, M. A. (2013). Standard errors and confidence intervals for scalability coefficients in Mokken scale analysis using marginal models. Sociological Methodology, 43, 42-69. https://doi.org/10.1177/0081175013481958
    • Kuijpers, R. E., van der Ark, L. A., & Croon, M. A. (2013). Testing hypotheses involving Cronbach’s alpha using marginal models. British Journal of Mathematical & Statistical Psychology, 66(3), 503-520. https://doi.org/10.1111/bmsp.12010
    • Richards, G. W., & van der Ark, L. A. (2013). Dimensions of cultural consumption among tourists: Multiple correspondence analysis. Tourism Management, 37, 71-76.
    • Straat, J. H., van der Ark, L. A., & Sijtsma, K. (2013). Comparing optimization algorithms for item selection in Mokken scale analysis. Journal of Classification, 30(1), 72-99. https://doi.org/10.1007/s00357-013-9122-y
    • Straat, J. H., van der Ark, L. A., & Sijtsma, K. (2013). Methodological artifacts in dimensionality assessment of the Hospital Anxiety and Depression Scale (HADS). Journal of Psychosomatic Research, 74(2), 116-121. https://doi.org/10.1016/j.jpsychores.2012.11.012
    • Zijlstra, W. P., van der Ark, L. A., & Sijtsma, K. (2013). Discordancy tests for outlier detection in multi item surveys. Methodology, 9(2), 69-77. https://doi.org/10.1027/1614-2241/a000056
    • van der Ark, L. A. (2013). Visualizing uncertainty of estimated response functions in nonparametric item response theory. In R. E. Millsap, L. A. van der Ark, D. M. Bolt, & C. M. Woods (Eds.), New developments in quantitative psychology: presentations from the 77th Annual Psychometric Society Meeting. (pp. 59-68). (Springer proceedings in mathematics and statistics; No. 66). New York: Springer. https://doi.org/10.1007/978-1-4614-9348-8_5

    2012

    • Bergsma, W. P., Croon, M. A., & van der Ark, L. A. (2012). The empty set and zero likelihood problems in maximum empirical likelihood. Electronic Journal of Statistics, 6, 2356-2361. https://doi.org/10.1214/12- EJS750
    • Straat, J. H., van der Ark, L. A., & Sijtsma, K. (2012). Multi-method analysis of the internal structure of the Type D Scale-14 (DS14). Journal of Psychosomatic Research, 72(4), 258-265. https://doi.org/10.1016/j.jpsychores.2012.01.005
    • Watson, R., van der Ark, L. A., Lin, L-C., Fieo, R., Deary, I. J., & Meijer, R. R. (2012). Item response theory: How Mokken scaling can be used in clinical practice. Journal of Clinical Nursing, 21, 2736-2746. https://doi.org/10.1111/j.1365-2702.2011.03893.x
    • van der Ark, L. A. (2012). New developments in Mokken scale analysis in R. Journal of Statistical Software, 48(5), 1-27. https://doi.org/10.18637/jss.v048.i05

    2011

    • Ligtvoet, R., van der Ark, L. A., Bergsma, W. P., & Sijtsma, K. (2011). Polytomous latent scales for the investigation of the ordering of items. Psychometrika, 76(2), 200-216. https://doi.org/10.1007/s11336-010-9199-8 [details]
    • Sijtsma, K., Meijer, R. R., & van der Ark, L. A. (2011). Mokken scale analysis as time goes by: An update for scaling practitioners. Personality and Individual Differences, 50, 31-37. https://doi.org/10.1016/j.paid.2010.08.016
    • Zijlstra, W. P., van der Ark, L. A., & Sijtsma, K. (2011). Outliers in questionnaire data: Can they be detected and should they be removed. Journal of Educational and Behavioral Statistics, 36, 186-212. https://doi.org/10.3102/1076998610366263
    • Zijlstra, W. P., van der Ark, L. A., & Sijtsma, K. (2011). Robust Mokken scale analysis by means of the forward search algorithm for outlier detection. Multivariate Behavioral Research, 46, 58-89. https://doi.org/10.1080/00273171.2011.544227
    • van der Ark, L. A., van der Palm, D. W., & Sijtsma, K. (2011). A latent class approach to estimating test-score reliability. Applied Psychological Measurement, 35, 380-392. https://doi.org/10.1177/0146621610392911

    2010

    • Ligtvoet, R., van der Ark, L. A., te Marvelde, J. M., & Sijtsma, K. (2010). Investigating an invariant item ordering for polytomously scored items. Educational and Psychological Measurement, 70(4), 578-595. https://doi.org/10.1177/0013164409355697 [details]
    • van der Ark, L. A. (2010). A note on stochastic ordering of the latent trait using the sum of polytomous item scores. Psychometrika, 75, 272-279. https://doi.org/10.1007/S11336-010-9147-7
    • van der Ark, L. A. (2010). Computation of the Molenaar Sijtsma statistic. In A. Fink, B. Lausen, W. Seidel, & A. Ultsch (Eds.), Advances in data analysis, data handling and business intelligence (pp. 775-784). Berlin: Springer.

    1999

    • van der Ark, L. A. (1999). Contributions to latent budget analysis; A tool for the analysis of compositional data. Leiden, The Netherlands: DSWO Press.

    2017

    • van der Ark, L. A., Wiberg, M., Culpepper, S. A., Douglas, J. A., & Wang, W-C. (Eds.) (2017). Quantitative psychology: The 81st Annual Meeting of the Psychometric Society, Asheville, North Carolina, 2016. (Springer Proceedings in Mathematics & Statistics; Vol. 196). Cham: Springer. https://doi.org/10.1007/978-3-319-56294-0 [details]

    2016

    • van der Ark, L. A., Bolt, D. M., Wang, W-C., Douglas, J. A., & Wiberg, M. (Eds.) (2016). Quantitative Psychology Research: The 80th Annual Meeting of the Psychometric Society, Beijing, 2015. (Springer Proceedings in Mathematics & Statistics; Vol. 167). Cham: Springer. https://doi.org/10.1007/978-3-319-38759-8 [details]

    2015

    • Millsap, R. E., Bolt, D. M., van der Ark, L. A., & Wang, W-C. (2015). Quantitative psychology research: the 78th Annual Meeting of the Psychometric Society. (Springer proceedings in mathematics & statistics; No. 89). Cham: Springer. https://doi.org/10.1007/978-3-319-07503-7 [details]
    • van der Ark, L. A., Bolt, D. M., Wang, W-C., Douglas, J. A., & Chow, S-M. (2015). Quantitative psychology research: the 79th Annual Meeting of the Psychometric Society, Madison, Wisconsin, 2014. (Springer proceedings in mathematics & statistics; No. 140). Cham: Springer. https://doi.org/10.1007/978-3-319-19977-1 [details]

    2014

    • Millsap, R. E., van der Ark, L. A., Bolt, D. M., & Woods, C. M. (Eds.) (2014). New developments in quantitative psychology: presentations from the 77th Annual Psychometric Society Meeting. (Springer proceedings in mathematics and statistics; No. 66). New York: Springer. https://doi.org/10.1007/978-1-4614-9348-8

    2013

    2012

    • Bergsma, W. P., Croon, M. A., Hagenaars, J. A. P., & van der Ark, L. A. (2012). Comment on Thas, De Neve and Ottoy (2012): Probablistic index models. Journal of the Royal Statistical Society, Series B, 74, 665-666.

    2008

    • Ligtvoet, R., van der Ark, L. A., & Sijtsma, K. (2008). Selection of Alzheimer symptom items with manifest monotonicity and manifest invariant item ordering. In K. Shigemasu, A. Okada, T. Imaizumi, & T. Hoshino (Eds.), New trends in psychometrics (pp. 225-234). Tokyo: Universal Academy Press.

    2005

    • van der Ark, L. A., Croon, M. A., & Sijtsma, K. (Eds.) (2005). New developments in categorical data analysis for the social and behavioral sciences. Mahwah, NJ: Erlbaum.

    2019

    • van der Ark, L. A., Korf, W., Peters, P. H., Chen, M., ten Hove, D., & Koopman, V. E. C. (2019). Onderzoek naar de verbetering van tests en vragenlijsten voor de pedagogische praktijk. In W. de Jong, J. Bekker, H. de Deckere, I. Schonewille, & L. van der Poel (Eds.), De belofte van de jeugd?!: Pedagogiek in de 21e eeuw (pp. 81-92). Amsterdam: SWP.

    2018

    • van der Ark, L. A., van Leeuwen, J. L., & Jorgensen, T. D. (2018). Interbeoordelaarsbetrouwbaarheid LIJ: Onderzoek naar de interbeoordelaarsbetrouwbaarheidheid van het Landelijk Instrument Jeugdstrafrechtketen. Amsterdam: Universiteit van Amsterdam. [details]

    2016

    • van der Ark, A. (2016). Psychometrie: Onderzocht, aangeleerd en toegepast. (Oratiereeks; No. 556). Amsterdam: Universiteit van Amsterdam. [details]
    • van der Ark, L. A. (2016). Kwantitatieve onderzoeksmethodologie ter bevordering van de academisering van het onderwijs. In L. Houweling, H. Viëtor, H. de Deckere, & W. de Jong (Eds.), De staat van de pedagogiek: Analytisch, opbrengstgericht en visionair (pp. 37-50). Amsterdam: SWP. [details]

    1995

    • van der Ark, L. A., Marburger, D., Mellenbergh, G. J., Vorst, H. C. M., & Wald, F. (1995). De aangepaste Profile of Moods States (Aangepaste POMS): Handleiding en verantwoording. Nijmegen: Berkhout.

    2018

    • Koopman, V. E. C., Zijlstra, B. J. H., & van der Ark, L. A. (2018). Checking assumptions in two-level Mokken scale analysis. Paper presented at VIII European Congress of Methodology, Jena, Germany.
    • ten Hove, D., Jorgensen, T. D., & van der Ark, L. A. (2018). Interrater reliability for dyad-level predictors in network data. Paper presented at XXXVIII Sunbelt 2018 Conference, Utrecht, Netherlands.

    2017

    • Koopman, V. E. C., de Rooij, M., Zijlstra, B. J. H., & van der Ark, L. A. (2017). Bias of two-level scalability coefficients and their standard errors. Paper presented at 82nd International Meeting of the Psychometric (IMPS) 2017, Zürich, Switzerland.

    2015

    • van der Ark, L. A. (2015). Divisive latent class models in R. Paper presented at International Workshop on Psychometric Computing (Psychoco) 2015, Amsterdam, Netherlands.
    • van der Ark, L. A. (2015). Multilevel Mokken scale analysis. Paper presented at 80th Annual Meeting of the Psychometric Society (IMPS) 2015, Beijing, China.

    2014

    • van der Ark, L. A. (Author). (2014). Mokken version 2.7.7 [computer software]. Software, Vienna, Austria: CRAN.

    Media appearance

    • van der Ark, L. A. (14-07-2014). Measurement [Print] Amsterdam, Coursera/University of Amsterdam. Measurement.

    Talk / presentation

    • van der Ark, A. (speaker) & Mulder, E. (speaker) (8-10-2019). De genealogie van de Nederlandse pedagogiek, VBSP Kennisfestival: Pedagoog durf te spelen, Garderen, Netherlands.
    • ten Hove, D. (speaker), Jorgensen, T. D. (speaker) & van der Ark, L. A. (speaker) (7-2019). Interrater reliability for multilevel data: A generalizability theory approach, 84th annual International Meeting of the Psychometric Society, Santiago, Chile.
    • van der Ark, A. (speaker) (2-2019). Do we agree?, University of Hong Kong.
    • ten Hove, D. (speaker), Jorgensen, T. D. (speaker) & van der Ark, L. A. (speaker) (2-2019). Applying generalizability theory to interdependent network data: Estimating interrater reliability, International Workshop on Psychometric Computing, Prague, Czech Republic.
    • ten Hove, D. (speaker), Jorgensen, T. D. (speaker) & van der Ark, L. A. (speaker) (1-2019). Applying generalizability theory to interdependent network data: Estimating interrater reliability, Annual Peer-Relations Researchers [Peer Relaties Onderzoekers] (PRO) meeting, Amsterdam, Netherlands.
    • Koopman, V. E. C. (speaker), Zijlstra, B. J. H. (speaker) & van der Ark, L. A. (speaker) (14-6-2018). Checking assumptions in two-level Mokken scale analysis, 33rd IOPS Summer Conference.
    • van der Ark, L. A. (speaker), Jorgensen, T. (speaker) & Sigurdardóttir, S. M. (speaker) (19-7-2017). Planning interrater reliability studies, International Meeting of the Psychometric Society 2017, Zürich, Switzerland.
    • van der Ark, L. A. (speaker) (5-10-2015). De VBSP en Kwantitatieve Onderzoeksmethodologie, VBSP congres 2015, Zeist, Netherlands.
    • van der Ark, L. A. (invited speaker) (5-2-2015). On divisive latent class models, Invited presentation, Rutgers, The State University of New Jersey, New Brunswick (NJ), USA.
    • van der Ark, L. A. (speaker) (29-9-2014). Meaningful measurement by means of multiple items, Paper presented at the AmsteRdam Meetup, Amsterdam, NL.
    • van der Ark, L. A. (speaker) (21-7-2014). Accuracy, bias, and precision in classical test theory, Paper presented 79th Annual Meeting of the Psychometric Society, Madison (WI), USA.
    • van der Ark, L. A. (speaker) (12-6-2014). Handling complex dependencies, Paper presented at The M&S Research Meeting, University of Amsterdam, Amsterdam, NL.
    • van der Ark, L. A. (speaker) (16-3-2014). Handling complex dependencies, Paper presented at Department of Methodology and Statistics, Tilburg University, Tilburg, The Netherlands.
    • van der Ark, L. A. (speaker) (13-2-2014). CMM: Categorical marginal models, Paper presented at the workshop Psychometric Computing 2014, Tübbingen, Germany.
    This list of publications is extracted from the UvA-Current Research Information System. Questions? Ask the library or the Pure staff of your faculty / institute. Log in to Pure to edit your publications. Log in to Personal Page Publication Selection tool to manage the visibility of your publications on this list.
  • Ancillary activities
    • Springer Publishing Company Adviseu
      r
    • Expertgroep Toetsen PO
      Psychometrisch secondant
    • CITO
      Adviseur
    • CITO
      Lid Wetenschappelijke Adviesraad
    • International Test Commission
      Editorial Board member
    • Psychometric Society
      Proceedings Editor
    • National Council Educational Measurement
      Associate editor Journal of Educational Measurement
    • Psychometric Society
      Lid Board of Trustees