Both Internet use's impact on depression and urban-rural disparities related to information and communication technologies (ICTs) are crucial topics in the information systems discipline. So far, limited studies have explored these topics in a comprehensive way. This study aims to explore the...

This paper derives a new method for comparing the weak-form efficiency of markets. The author derives the formula of the Sharpe ratio from the ARMA-GARCH model and finds that the Sharpe ratio just depends on the coefficients of the AR and MA terms and is not affected by the GARCH process. For...

This paper explores the effects of innovation efficiency on technology gap and product diversity between a leading firm and its competitor. Our analysis shows some interesting results: when innovation efficiency is sufficiently large and increases, the leading firm may expand technology gap, and...