Editorial statement and research ideas for behavioral economics and behavioral finance Both Behavioral Economics and Behavioral Finance are the milestones of modern development in both Economics and Finance because many empirical phenomena, anomalies and paradoxes cannot be explained by traditional theories in Economics and Finance. For example, the Efficient Market Hypothesis concludes that no investor can perform better than the market because the hypothesis claims that all the information has been reflected in stock prices. Nonetheless, it is well known that some investors not only perform better than other investors but also outperform the market. Moreover, some anomalies and paradoxes, for example, the diversification puzzle, the Friedman-Savage paradox, overreaction, under-reaction and excess volatility, could persist while some other anomalies could die off, for example, the January effect, and some could re-appear again.To explain empirical phenomena and explain some paradoxes and anomalies that cannot be explained by traditional theories, academics can use the ideas from both Behavioral Economics and Behavioral Finance. To do so, academics can first develop theoretical theories and thereafter establish the corresponding econometric estimations or testing models in Behavioral Economics and Behavioral Finance. They could examine both powers and sizes and determine whether the econometric estimation or testing is efficient. Thereafter, scholars could use the models to study some interesting problems in Behavioral Economics and Behavioral Finance.There are many directions in developing theories for Behavioral Economics and Behavioral Finance. For example, one can develop theories for different utility functions, like utilities of risk aversion, risk-seeking, regret aversion and disappointment aversion, S-shaped and reverse S-shaped utility functions and multivariate utility functions. One could develop theories for different risk measures, including mean-variance rules, Sharpe ratio, Omega ratio, Value-at-Risk (VaR), conditional-VaR, Kappa ratio, Farinelli-Tibiletti ratio and economic performance measure. There are many other theories for Behavioral Economics and Behavioral Finance, for example, stochastic dominance (SD), almost SD and indifference curves for different types of utility functions, arbitrage opportunity and market efficiency, portfolio optimization, capital asset pricing model, diversification, models with Background Risk (Guo et al., 2018), Bayesian models for investors with conservatism and representativeness heuristics (Lam et al., 2010) and investors' behavior model with segregating or integrating multiple outcomes (Egozcue et al., 2014), cost of capital (Wong and Chan, 2004), economic and financial indicators, technical analysis, trading rules, trading strategies, contagion, cointegration, causality, nonlinearity, jump, wavelet and copulas. There are also many applications by using the theories in Behavioral Economics and Behavioral Finance. Readers may refer to Wong (2020) for more infor...