The article explores the economic transition and EU enlargement in East European countries using a quantitative approach. Researchers analyze factors like financial markets, GDP growth, agriculture, wages, and stock markets in countries like Latvia, Hungary, Poland, and Romania. They use methods like Markov chains, econometric models, and simulation results to understand the impact of EU accession on these economies. Key findings include the response of the external sector to transition, the effects of agricultural accession on welfare, and the dynamics of wage and price inflation during the transition period. The study also examines the maturity of stock exchanges in countries like Poland and the volatility of stock returns in Central and Eastern Europe.