Contemporary research designs and data analysis techniques in educational research

Sa？etak Contemporary educational research is based on the use of appropriate research designs, comprehensive data assessments and contemporary models of the data analysis. Methodological breakthroughs in this area, over the last few decades, are significant, and researchers have recognized the importance of longitudinal research designs. Moreover, the understanding of the hierarchical organization of collected data and the application of corresponding statistical analyses becomes a methodological imperative. This paper provides a methodological overview of hierarchical and longitudinal data organization and the theoretical framework of their statistical analysis. Most common errors and difficulties in the application of those methods are highlighted, and the approaches on how to overcome it are suggested. Through simple and everyday examples, these approaches are presented to the readers, and educational researchers are directed on how to adequately use it