I am a methodologist working on data science applications in social research, digital exclusion, and ethical questions in this area, as well as response behavior, measurement and nonresponse errors.
From 2012 to 2022 I was the Director of the German Internet Panel (GIP), a bi-monthly longitudinal online survey of more than 5,000 individuals based on a probability sample of the general population. The GIP is funded by the German Science Foundation (DFG).
I am also involved in several research projects at the Collaborative Research Center “Political Economy of Reforms” (SFB 884) and the Mannheim Center for European Social Research (MZES) and conduct research at the Mannheim Center for Data Science.
Employment history and education
Employment history
07/ 2017 Research Professor for Data Science, School of Social Sciences, University of Mannheim 08/ 2012 Assistant Professor for Methods of Empirical Social Research, School of Social Sciences, University of Mannheim 03/ 2011 Owner of Survex – Surveys, Statistics, Data Science 01/ 2010 Head of Unit Survey Methods, Survey of Health, Ageing and Retirement in Europe (SHARE), Mannheim Research Institute for the Economics of Aging (MEA), University of Mannheim 05/ 2005 Researcher, European Social Survey (ESS), GESIS – Leibniz Institute for Social Sciences, Mannheim 09/ 2003 Researcher, Education Group, National Centre for Social Research (NatCen), London Education
07/ 2018 Postgraduate Certificate in Big Data & Business Analytics, University of Leuven, Belgium 11/ 2009 Ph.D. in Applied Social and Economic Research, University of Essex, England 07/ 2003 M.Phil. in European Politics and Society, University of Oxford, England 07/ 2001 Certificate in Music (Trombone), University of the Arts Utrecht, Netherlands 07/ 2001 B.A. in Social Sciences, University College Utrecht, Netherlands Publications
2022
- Cornesse, C., Felderer, B., Fikel, M., Krieger, U. & Blom, A. G. (2022). Recruiting a probability-based online panel via postal mail: Experimental evidence. Social Science Computer Review : SSCORE, 40(5), 1259–1284. https://doi.org/10.1177/08944393211006059
- Cornesse, C., Gonzalez Ocanto, M., Fikel, M., Friedel, S., Krieger, U., Rettig, T. & Blom, A. G. (2022). Measurement instruments for fast and frequent data collection during the early phase of COVID-19 in Germany: reflections on the Mannheim Corona Study. Measurement Instruments for the Social Sciences : MISS, 4(Article 2), 1–7. https://doi.org/10.1186/s42409-022-00030-5
- Cornesse, C., Krieger, U., Sohnius, M.-L., Fikel, M., Friedel, S., Rettig, T., Wenz, A., Juhl, S., Lehrer, R., Möhring, K., Naumann, E., Reifenscheid, M. & Blom, A. G. (2022). From German Internet Panel to Mannheim Corona Study: Adaptable probability-based online panel infrastructures during the pandemic. Journal of the Royal Statistical Society. Series A, Statistics in Society, 185(3), 773–797. https://doi.org/10.1111/rssa.12749
- Felderer, B. & Blom, A. G. (2022). Acceptance of the automated online collection of geographical information. Sociological Methods & Research : SMR, 51(2), 866–886. https://doi.org/10.1177/0049124119882480
- Gavras, K., Höhne, J. K., Blom, A. G. & Schoen, H. (2022). Innovating the collection of open-ended answers: The linguistic and content characteristics of written and oral answers to political attitude questions. Journal of the Royal Statistical Society. Series A, Statistics in Society, 185(3), 872–890. https://doi.org/10.1111/rssa.12807
2021
- Felderer, B., Herzing, J. M. E., Bruch, C., Krieger, U. & Blom, A. G. (2021). How does switching a probability-based online panel to a smartphone-optimized design affect response rates and smartphone use? Survey Methods : Insights from the Field, 2021, 1–13. https://doi.org/10.13094/SMIF-2021-00007
- Mata, J., Wenz, A., Rettig, T., Reifenscheid, M., Möhring, K., Krieger, U., Friedel, S., Fikel, M., Cornesse, C., Blom, A. G. & Naumann, E. (2021). Health behaviors and mental health during the COVID-19 pandemic: A longitudinal population-based survey in Germany. Social Science & Medicine, 287(Article 114333). https://doi.org/10.1016/j.socscimed.2021.114333
- Möhring, K., Naumann, E., Reifenscheid, M., Wenz, A., Rettig, T., Krieger, U., Friedel, S., Fikel, M., Cornesse, C. & Blom, A. G. (2021). The COVID-19 pandemic and subjective well-being: longitudinal evidence on satisfaction with work and family. European Societies, 23(Suppl. 1), S601–S617. https://doi.org/10.1080/14616696.2020.1833066
- Rettig, T. & Blom, A. G. (2021). Memory effects as a source of bias in repeated survey measurement. In A. Cernat & J. W. Sakshaug (eds.), Measurement error in longitudinal data (S. 3–18). Oxford ; New York, NY: Oxford University Press.
2020
- Blom, A. G., Cornesse, C., Friedel, S., Krieger, U., Fikel, M., Rettig, T., Wenz, A., Juhl, S., Lehrer, R., Möhring, K., Naumann, E. & Reifenscheid, M. (2020). High-frequency and high-quality survey data collection: The Mannheim Corona study. Survey Research Methods : SRM, 14(2), 171–178. https://doi.org/10.18148/srm/2020.v14i2.7735
- Blom, A. G., Cornesse, C., Sakshaug, J. W. & Wenz, A. (2020). Recent advances in probability-based and nonprobability survey research. Journal of Survey Statistics and Methodology : JSSAM, 8(1), 2–3. https://doi.org/10.1093/jssam/smaa002
- Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Das Leben in Deutschland im Ausnahmezustand : Bericht zur Lage vom 20. März bis 29. April 2020.
- Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Das Leben in Deutschland im Ausnahmezustand : Bericht zur Lage vom 20. März bis 30. Juni 2020. Mannheim.
- Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). The Mannheim Corona Study: Life in Germany in a state of emergency : Report for March 20 to June 30, 2020 ; English translation of the original report (in German). Mannheim.
- Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). The Mannheim Corona study: Life in Germany in a state of emergency : Report for March 20 to July 09, 2020. Mannheim.
- Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). The Mannheim Corona study: life in Germany in a state of emergency : report for March 20 to May 28, 2020, English translation of the original report (in German). Mannheim.
- Cornesse, C. & Blom, A. G. (2020). Response quality in nonprobability and probability-based online panels. Sociological Methods and Research : SMR, 1–30. https://doi.org/10.1177/0049124120914940
- Cornesse, C., Blom, A. G., Dutwin, D., Krosnick, J. A., de Leeuw, E., Legleye, S., Pasek, J., Pennay, D., Phillips, B., Sakshaug, J. W., Struminskaya, B. & Wenz, A. (2020). A review of conceptual approaches and empirical evidence on probability and nonprobability sample survey research. Journal of Survey Statistics and Methodology : JSSAM, 8(1), 4–36. https://doi.org/10.1093/jssam/smz041
- Höhne, J. K., Schlosser, S., Couper, M. P. & Blom, A. G. (2020). Switching away: Exploring on-device media multitasking in web surveys. Computers in Human Behavior, 111(Article 106417). https://doi.org/10.1016/j.chb.2020.106417
- Juhl, S., Lehrer, R., Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Krieger, U., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Demokratische Kontrolle in der Corona-Krise. Mannheim.
- Juhl, S., Lehrer, R., Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Krieger, U., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Gesellschaftliche Akzeptanz politischer Maßnahmen und befürchtete Konsequenzen für die Wirtschaft. Mannheim.
- Lehrer, R., Juhl, S., Blom, A. G., Wenz, A., Rettig, T., Reifenscheid, M., Naumann, E., Möhring, K., Krieger, U., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Die vier Phasen des Social Distancing in Deutschland. Mannheim.
- Möhring, K., Heinemann, F., Naumann, E., Reifenscheid, M., Blom, A. G., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Schwerpunktbericht zum subjektiven Arbeitslosigkeitsrisiko der Beschäftigten in Deutschland. Mannheim.
- Möhring, K., Naumann, E., Reifenscheid, M., Blom, A. G., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Schwerpunktbericht zu Erwerbstätigkeit und Kinderbetreuung. Mannheim.
- Möhring, K., Naumann, E., Reifenscheid, M., Blom, A. G., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Schwerpunktbericht zur Erwerbstätigkeit in Deutschland 20.3.-15.4.2020. Mannheim.
- Möhring, K., Naumann, E., Reifenscheid, M., Weiland, A., Blom, A. G., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M. & Cornesse, C. (2020). Die Mannheimer Corona-Studie: Schwerpunktbericht zur Nutzung und Akzeptanz von Homeoffice in Deutschland während des Corona-Lockdowns. Mannheim.
- Naumann, E., Mata, J., Reifenscheid, M., Möhring, K., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M., Cornesse, C. & Blom, A. G. (2020). Die Mannheimer Corona-Studie: Schwerpunktbericht zum Angstempfinden in der Bevölkerung. Mannheim.
- Naumann, E., Möhring, K., Reifenscheid, M., Wenz, A., Rettig, T., Lehrer, R., Krieger, U., Juhl, S., Friedel, S., Fikel, M., Cornesse, C. & Blom, A. G. (2020). COVID‐19 policies in Germany and their social, political, and psychological consequences. European Policy Analysis : EPA, 6(2), 191–202. https://doi.org/10.1002/epa2.1091
- Stark, T. H., Silber, H., Krosnick, J. A., Blom, A. G., Aoyagi, M., Belchior, A., Bosnjak, M., Clement, S. L., Melvin, J., Guðbjörg, A. J., Lawson, K., Lynn, P., Martinsson, J., Shamshiri-Petersen, D., Tvinnereim, E. & Yu, R.-. (2020). Generalization of classic question order effects across cultures. Sociological Methods & Research : SMR, 49(3), 567–602. https://doi.org/10.1177/0049124117747304
- Wiśniowski, A., Sakshaug, J. W., Perez Ruiz, D. A. & Blom, A. G. (2020). Integrating probability and nonprobability samples for survey inference. Journal of Survey Statistics and Methodology : JSSAM, 8(1), 120–147. https://doi.org/10.1093/jssam/smz051
2019
- Herzing, J. M. E. & Blom, A. G. (2019). The influence of a person’s digital affinity on unit nonresponse and attrition in an online panel. Social Science Computer Review : SSCORE, 37(3), 404–424. https://doi.org/10.1177/0894439318774758
- Sakshaug, J. W., Perez Ruiz, D. A., Wiśniowski, A. & Blom, A. G. (2019). Supplementing small probability samples with nonprobability samples: A Bayesian approach. Journal of Official Statistics : JOS, 35(3), 653–681. https://doi.org/10.2478/jos-2019-0027
2018
- Blom, A. G. & Korbmacher, J. M. (2018). Linking survey data to administrative records in a comparative survey context. In D. L. Vannette (eds.), The Palgrave handbook of survey research (S. 267–273). Cham: Palgrave Macmillan. https://doi.org/10.1007/978-3-319-54395-6_34
- Silber, H., Stark, T. H., Blom, A. G. & Krosnick, J. A. (2018). Implementing a multinational study of questionnaire design. In T. P. Johnson (eds.), Advances in comparative survey methods : multinational, multiregional, and multicultural contexts (3MC) (S. 161–180). Hoboken, NJ: Wiley. https://doi.org/10.1002/9781118884997.ch8
2017
- Blom, A. G. & Herzing, J. M. E. (2017). Face-to-face Rekrutierung für ein probabilistisches Onlinepanel. In F. Faulbaum (eds.), Methodische Probleme von Mixed-Mode-Ansätzen in der Umfrageforschung (S. 99–118). Wiesbaden: Springer VS. https://doi.org/10.1007/978-3-658-15834-7_4
- Blom, A. G., Herzing, J. M. E., Cornesse, C., Sakshaug, J. W., Krieger, U. & Bossert, D. (2017). Does the recruitment of offline households increase the sample representativeness of probability-based online panels? Evidence from the German internet panel. Social Science Computer Review : SSCORE, 35(4), 498–520. https://doi.org/10.1177/0894439316651584
- West, B. T. & Blom, A. G. (2017). Explaining interviewer effects : a research synthesis. Journal of Survey Statistics and Methodology : JSSAM, 5(2), 175–211. https://doi.org/10.1093/jssam/smw024
2016
- Blom, A. G. (2016). Survey fieldwork. In C. Wolf (eds.), The SAGE handbook of survey methodology (S. 382–396). London: SAGE Publications. https://doi.org/10.4135/9781473957893.n25
- Blom, A. G., Bosnjak, M., Cornilleau, A., Cousteaux, A.-S., Das, M., Douhou, S. & Krieger, U. (2016). A comparison of four probability-based online and mixed-mode panels in Europe. Social Science Computer Review : SSCORE, 34(1), 8–25. https://doi.org/10.1177/0894439315574825
2015
- Blom, A. G., Gathmann, C. & Krieger, U. (2015). Setting up an online panel representative of the general population : the German Internet panel. Field Methods, 27(4), 391–408. https://doi.org/10.1177/1525822X15574494
- Gebhard, F. & Blom, A. G. (2015). Frauke Kreuter (Editor) (2013): Improving Surveys with Paradata. Analytic Uses of Process Information. Wiley Series in Survey Methodology ISBN: 978-0-470-90541-8, 416 pages, €65.70. Review, Methods, Data, Analyses : MDA. https://doi.org/10.12758/mda.2015.006
- Pforr, K., Blohm, M., Blom, A. G., Erdel, B., Felderer, B., Fräßdorf, M., Hajek, K., Helmschrott, S., Kleinert, C., Koch, A., Krieger, U., Kroh, M., Martin, S., Saßenroth, D., Schmiedeberg, C., Trüdinger, E.-M. & Rammstedt, B. (2015). Are incentive effects on response rates and nonresponse bias in large-scale face-to-face surveys generalizable to Germany? Evidence from ten experiments. Public Opinion Quarterly : POQ, 79(3), 740–768. https://doi.org/10.1093/poq/nfv014
- Spindler, G., Blom, A. G. & Thorun, C. (2015). Die Evaluation der Button-Lösung : Ergebnisse einer empirischen Studie. Multimedia und Recht : MMR, 18(1), 3–7.
2014
- Blom, A. G. (2014). Setting priorities : spurious differences in response rates. International Journal of Public Opinion Research, 26(2), 245–255. https://doi.org/10.1093/ijpor/edt023
- Thorun, C., Spindler, G. & Blom, A. G. (2014). Evaluation des Gesetzes zum besseren Schutz der Verbraucher vor Kostenfallen im elektronischen Geschäftsverkehr : Abschlussbericht, Aktenzeichen: 314-06.01-2813HS010, Laufzeit: September 2013 bis August 2014.
2013
- Blom, A. G. & Korbmacher, J. M. (2013). Measuring interviewer characteristics pertinent to social surveys : a conceptual framework. Survey Methods : Insights from the Field, [1]([1]), 1–16. https://doi.org/10.13094/SMIF-2013-00001
- Blom, A. G., Schaan, B. & Korbmacher, J. M. (2013). Paradaten im SHARE. In H.-G. Soeffner (eds.), Transnationale Vergesellschaftungen : Verhandlungen des 35. Kongresses der Deutschen Gesellschaft für Soziologie in Frankfurt am Main 2010 Bd. CD-ROM (S. ). Wiesbaden: Springer VS.
2012
- Blom, A. G. (2012). Explaining cross‐country differences in survey contact rates : application of decomposition methods. Journal of the Royal Statistical Society. Series A, Statistics in Society, 175(1), 217–242. https://doi.org/10.1111/j.1467-985X.2011.01006.x
2011
- Blom, A. G. & Kreuter, F. (2011). Preface [Special issue: International Workshop on Household Survey Nonresponse]. Journal of Official Statistics : JOS, 27(2), 151–152.
- Blom, A. G., de Leeuw, E. & Hox, J. J. (2011). Interviewer effects on nonresponse in the European social survey. Journal of Official Statistics : JOS, 27(2), 359–377.
- Blom, A. G. & Schröder, M. (2011). Sample composition 4 years on : retention in SHARE Wave 3. In M. Schröder (eds.), Retrospective data collection in the survey of health, ageing and retirement in Europe : SHARELIFE methodology (S. 55–61). Mannheim: MEA, Mannheim Research Institute for the Economics of Ageing.
2010
- Blom, A. G., Jäckle, A. & Lynn, P. (2010). The use of contact data in understanding cross‐national differences in unit nonresponse. In J. A. Harkness (eds.), Survey methods in multinational, multiregional, and multicultural contexts (S. 333–354). Hoboken, NJ: Wiley. https://doi.org/10.1002/9780470609927.ch18
2009
- Blom, A. G. (2009). Explaining cross-country differences in contact rates. ISER Working Paper Series, 09-08. Colchester: ISER, University of Essex.
- Blom, A. G. (2009). Measuring, explaining and adjusting for cross-country differences in unit nonresponse : what can process data contribute? [Doctoral dissertation, University of Essex].
- Blom, A. G. (2009). Nonresponse bias adjustments : what can process data contribute? ISER Working Paper Series, 09-21. Colchester: ISER, University of Essex.
2008
- Blom, A. G. (2008). Measuring nonresponse cross-nationally. ISER Working Paper Series, 08-41. Colchester: ISER, University of Essex.
- Blom, A. G., Lynn, P. & Jäckle, A. (2008). Understanding cross-national differences in unit non-response: the role of contact data. ISER Working Paper Series, 08-01. Colchester: ISER, University of Essex.
2006
- Barnes, M., Blom, A. G., Cox, K., Lessof, C. & Walker, A. (2006). The social exclusion of older people : evidence from the first wave of the English Longitudinal Study of Ageing (ELSA), Final Report. London: Office of the Deputy Prime Minister ; The Institute for Fiscal Studies.
- Blom, A. G., Doerr, L. A., Cheung, G.-., Liu, Y. & Harkness, J. (2006). Translations and interpreting : what do survey organizations do? Survey Research : Newsletter, 37(1/2), 1–6.
- Finch, S., Aye Maung, N., Jones, A., Tipping, S., Blom, A. G. & Ghate, D. (2006). National evaluation of On Track Phase Two : report of the first wave of the longitudinal cohort study; final report to the Department for Education and Skills. London: National Centre for Social Research.
- Finch, S., Aye Maung, N., Jones, A., Tipping, S., Blom, A. G. & Ghate, D. (2006). The national evaluation of On Track Phase Two : report of the first wave of the longitudinal cohort study; technical and methods report. London: National Centre for Social Research.
2003
- Blom, A. G. (2003). Educational systems and political tolerance : a cross-national study in 30 countries. Thesis, . Oxford.