This volume presents a selection of peer-reviewed papers that address the latest developments in the methodology and applications of data analysis and classification tools to micro- and macroeconomic problems. The contributions were originally presented at the 30th Conference of the Section on Classification and Data Analysis of the Polish Statistical Association, SKAD 2021, held online in Poznań, Poland, September 8–10, 2021. 

Providing a balance between methodological and empirical studies, and covering a wide range of topics, the book is divided into five parts focusing on methods and applications in finance, economics, social issues and to COVID-19 data. The book is aimed at a wide audience, including researchers at universities and research institutions, PhD students, as well as practitioners, data scientists and employees in public statistical institutions.

Methods.- Abstract Fuzzy Cognitive Maps as a Toll for Structuring New Research Problems.- Identification of key concerns and sentiments towards data quality and data strategy challenges using Sentiment Analysis and Topic Modeling.- Survival Trees and Direct Adjusted Survival Curves - Prediction of Survival Probabilities.- A Measure of Cluster Stability in Dynamic Cluster Analysis.- Outlier Identification for Symbolic Data with the Application of the DBSCAN Algorithm.- An optimised selection of statistical disclosure control methods – a case study involving microdata from the Polish survey of accidents at work.- Applications in Finance.- Comparison of Influence of Various Proposals of Transforming Nominants Into Stimulants on Linear Ordering and Grouping of Listed Companies.- Attributes affecting the exposure time of a residential property.- Determinants of the real estate prices in Poland.- Similarity of open-ended mutual funds during a pandemic. Research for equity and bond funds.-Applications in Economics.- Application of random forests in the study of differences in perception of the neighbourhood of national parks in the Euroregion Pomerania.- Successes and failures of scientific journals and their determinants.- Spatial effects in regional inequality analysis of own income potential among Polish communes.- Evaluation of quality of neural network models and discriminant analysis in ROPO forecasting.- The Application of Survival Analysis Methods in the Examination of Foreign Divestment in Poland.- Longevity risk versus longevity dividend.- Applications in Social Issues.- Application of the Intuitionistic Fuzzy Synthetic Measure in the subjective quality of life measurement based on survey data.- Measuring Subjective Poverty: Methodological and Application Aspects.- Graphic characters as Twitter age group identifiers.- Cluster Ensemble Stability in Clustering of EU Members in Terms of Sustainable Development Goals.- Perception of climate change – differences between the Y and BB generations.- Applications with COVID-19 Data.- Cash and non-cash payments for in-store purchases during the COVID-19 pandemic - similarities and differences between Generation X and Generation Y consumers. Case of Poland.- Regional labour markets as a result of the impact of the COVID-19 pandemic – a Polish-German borderland case study.- The Labour Market Consequences of the COVID-19 Pandemic in the European Union Countries: Selected Issues.- Analysis of the excessive number of deaths related to the COVID-19 pandemic in European countries.