A number of studies on the S&P 500 index options market claim that the no arbitrage assumption cannot be rejected for this market because either the martingale restriction defined in Longstaff (1995) cannot be rejected by the data, or, even when it is rejected, a large proportion of the...

This study explores the relationship between financial firms' environmental, social, and governance (ESG) activities and their financial stability measured by Altman's Z-score. Based on a dataset of listed financial institutions in Korea, our results indicate a positive association between...

The authors re-examine the return-volatility relationship and its dynamics under a new vector autoregression (VAR) identification framework. By analyzing two model-free impliedvolatility indices – the well-established VIX (in the United States) and the recently published VKOSPI (in Korea) –...