This book mainly focuses on the application of psychology to applied economics and teaching practice. Representative cases include the following studies: (1) Exploring the Impact of the Escalation of Sino-US Trade Friction on China's Soybean Imports from the Perspective of Investor's Psychological Anxiety; (2) The Impact of Digital Financial Inclusion on Female Employment in China: From the Perspective of Solving the Employment Dilemma and Realizing Psychological Happiness; (3) Empirical Analysis of Infrastructure Construction on Export Performance of Trade in Services under the Belt and Road Initiative Considering Psychological Needs and Happiness Levels; (4) A New Research Framework of International Development of Strategic Emerging Industries considering Residents' Happiness and Psychological Analysis of Decision Makers; (5) Directors' and Executives' Liability Insurance and Investment Efficiency: A Study Based on Managers' Psychological Anxiety and Management Defense Theory; (6) The Impact of Online Teaching on Students' Mental Health State and Happiness of Promoting Teaching and Learning.