The symposium will investigate how educational policies influence educational outcomes worldwide. One of the most salient findings in the field of education is that there are huge national differences in student achievement in international comparative studies (e.g., Mullis, Martin, Foy, & Arora, 2012; OECD, 2014). The shockingly large gap between the highest performing countries (most of which are in East Asia) and many European countries corresponds to a difference in attainment of two years of schooling. Although this finding has been replicated in several studies, at present, the reasons for and consequences of such differences are not well understood at present (Strietholt, Bos, Gustafsson, & Rosén, 2014).

Variations in many features of educational policies can only be observed across countries on the system level (e.g., the existence of central exams; see Hanushek & Woessmann, 2011). Since the start of the new millennium, a new generation of international comparative studies has been launched: studies like PISA and TIMSS are repeated every few years and thus have a longitudinal component at the system level. Unlike cross-sectional designs, these trend designs allow the causal effects of changes in educational policies at the system level to be estimated. Applying this approach, alongside other approaches to causal inference, to the accumulated data from the comparative studies has a huge potential to provide insights into the determinants of educational outcomes worldwide (Hanushek & Woessmann, 2011; Strietholt & Scherer, 2017).

In order to provide a holistic perspective on education worldwide, the symposium is divided into three session that address: 1) The Integrity of Educational Outcome Measures, 2) Governance of Human and Financial Resources and Decision Making, and 3) Educational Settings and Processes. All contributions make use of the international comparative studies of educational achievement around the globe (e.g., TIMSS, PISA). These studies are producing data at an increasing rate, which are used in secondary analyses to study differences between and within countries.

During the last two decades, there have been methodological developments that made it possible to address issues that were previously impossible to study. The symposium aims to make use of these developments and to apply them to the data of international assessments. Specifically, in the fields of educational and psychological measurement, remarkable and powerful statistical methods have emerged due to the evolution of modern test theory or item response theory (IRT) and its implementation in computer software. Another important strand of development concerns analytical approaches that allow valid causal inferences based on observational data (e.g., differences-in-differences, longitudinal designs on country level). The different contributions make use of these new analytical approaches (e.g., Angrist & Pischke, 2009; Boeck & Wilson, 2004).

As a result of our engagement with international assessments, we will also develop a critical perspective on these studies. We will explore the opportunities but also misuse, misinterpretations and other limitations of using international assessment data for research on educational systems. We conduct comparative research and use data from up to 100 countries worldwide including most European countries. The authors represent a wide range of nationalities including Mexico, Greece, Cyprus, Ukraine, Hungary, Sweden, Canada, UK, China, Belgium, Bosnia and Herzegovina, Chile, and the US.

Angrist, J. D., & Pischke, J.-S. (2008). Mostly harmless econometrics: An empiricist's companion. Princeton, New Jersey: Princeton University Press. Boeck, D., & Wilson, M. (2004). Explanatory item response models: a generalized linear and nonlinear approach. New York: Springer. Mullis, I. V. S., Martin, M. O., Foy, P., & Arora, A. (2012). TIMSS 2011 international results in mathematics. Chestnut Hill, MA: TIMSS & PIRLS International Study Center, Boston College. OECD (2014). PISA 2012 results: What students know and can do. Student performance in mathematics, reading, and science (volume 1, revised edition): OECD Publishing. Strietholt, R., & Scherer, R. (2017). The contribution of international large-scale assessments to educational research: Combining individual and institutional data sources. Scandinavian Journal of Educational Research, 1-18. Strietholt, R., Bos, W., Gustafsson, J. E., & Rosén, M. (2014). Educational policy evaluation through international comparative assessments. Münster/New York: Waxmann. Hanushek, E. A., & Wößmann, L. (2011). The economics of international differences in educational achievement. In E. A. Hanushek, S. Machin, & L. Wößmann (Eds.), Handbook of the economics of education. Amsterdam: Elsevier.