Shift-Volatility Transmission in East Asian Equity Markets

This paper attempts to provide evidence of "shift-volatility" transmission in the East Asian equity markets. By shift-volatility, we mean the volatility shifts from a low level to a high level, corresponding respectively to tranquil and crisis periods. We examine the interdependence of equity volatilities between Hong-Kong, Indonesia, Japan, Malaysia, the Philippines, Singapore, Thailand and the United States. Our main issue is whether shift-volatility needs to be considered as a regional phenomenon, or from a more global perspective. We find that the timing/spans of high volatility regimes correspond adequately to years historically documented as those of crises (the Asian crisis and the years following the 2008 crisis). Moreover, we suggest different indicators that could be useful to guide the investors in their arbitrage behavior in the different regimes: the duration of each state, the sensitivity of the volatility in a market following a change in the volatility in another market. Finally, we are able to identify which market can be considered as leading markets in terms of volatility

Randomised controlled study of conjunctival autograft versus amniotic membrane graft in pterygium excision

AIM: To determine whether amniotic membrane can be used as an alternative to conjunctival autograft after pterygium excision. METHODS: 287 eyes with either primary or recurrent pterygium were included in this study. All eyes were randomised to undergo conjunctival autograft or amniotic membrane transplantation after pterygium excision by a single surgeon. 106 eyes in primary pterygium and 14 eyes in the recurrent group were treated with conjunctival autograft, and 148 eyes in primary pterygium and 19 eyes in the recurrent group were treated with amniotic membrane transplantation. Patients were followed up at 6 weeks and 6 months after operation. The main outcome measurement was recurrence rate after surgery. RESULTS: In the conjunctival group, the recurrence rate was 12.3%, 21.4% and 13.1% for primary, recurrent and all pterygia, respectively. In the amniotic membrane group, the recurrence rate was 25.0%, 52.6% and 28.1% for primary, recurrent and all pterygia, respectively. The recurrence rate for all pterygia in the amniotic membrane group was significantly higher than that in the conjunctival group (p = 0.003). CONCLUSIONS: Amniotic membrane graft had a higher recurrence rate than conjunctival autograft. However, it is an alternative choice, especially for advanced cases with bilateral heads or patients who might need glaucoma surgery later

Shift-volatility transmission in East Asian equity markets: new indicators

This paper attempts to provide evidence of “shift-volatility” transmission in the East Asian equity markets. By “shift-volatility”, we mean the volatility shifts from a low level to a high level corresponding respectively to tranquil and crisis periods. We examine the interdependence of equity volatilities between Hong-Kong, Indonesia, Japan, Malaysia, the Philippines, Singapore, Thailand and the United States. Our main issue is whether shift-volatility needs to be considered as a regional phenomenon, or from a more global perspective. We propose several indicators that are be useful to guide the investors in their arbitrage behavior in the different regimes: the duration of each state, the sensitivity of the volatility in a market following a change in the volatility in another market. Finally, we are able to identify which market can be considered as leading markets in terms of volatility