Title: PISA Data Analysis Leveraging R: Pros and Cons Author: Mariia Mazorchuk, Anna Bychko Affiliation: Ukrainian Center for Educational Quality Assessment Abstract: In 2018, for the first time Ukraine participated in the PISA program that aims to evaluate the quality of education system and find a way to improve it. The team of data analysts from the Ukrainian center of educational quality assessment preprocessed and analyzed the PISA data and announced the assessment results in 2019. The team worked with a large scale assessment and that task requires specific tools. Thus, our software team utilized the following tools such as SPSS (http://www.spss.com.hk/software/statistics/), IDB Analyzer (https://www.iea.nl/data-tools/tools#section-308) and PISA Data Explorer (https://pisadataexplorer.oecd.org/ide/idepisa/). For most operations, we utilized R software, in particular, the intsvy package (https://cran.r-project.org/web/packages/intsvy/intsvy.pdf) that provides for calculations descriptive statistics, regression and correlation coefficients, frequency tables for PISA data (including the complex sample design with replicate weights) and rotated test forms with plausible values of achievement scores. To visualize the data we leveraged the intsvy package and some additional packages such as ggplot. During the calculation process, we encountered some issues such as the inability to process the PISA dataset that includes all countries and to calculate the complex estimates. To solve the issues with PISA data analysis we leveraged R functions and since the packages of R Software Environment were in open access, we performed the necessary calculations of statistical characteristics. Here we present the project's results and share the experience of processing PISA data with R functions.