This paper considers the issue of whether shocks to ten commodity prices (gold, silver, platinum, copper, aluminum, iron ore, lead, nickel, tin, and zinc) are persistent or transitory. We use two recently developed unit root tests, namely the Narayan and Popp (NP, 2010) test and the Liu and...

This paper considers the issue of whether shocks to ten commodity prices (gold, silver, platinum, copper, aluminum, iron ore, lead, nickel, tin, and zinc) are persistent or transitory. We use two recently developed unit root tests, namely the Narayan and Popp (NP) [14] test and the Liu and...

In this paper, we test the efficient market hypothesis for 100 US firms listed on the New York Stock Exchange. To test the unit root null hypothesis, we develop a generalized autoregressive heteroskedasticity (GARCH) model that not only caters for the GARCH errors but also allows for two...

In this note, we consider the relationship between oil price volatility and firm returns for 560 firms listed on the New York Stock Exchange. Using daily time series data from 2000 to 2008, we find that oil price volatility increases firm returns for the majority of the firms in our sample.

The aim of this paper is to examine the impact of US macroeconomic conditions—namely, exchange rate and short-term interest rate—on the stocks of seven Asian countries (China,India, the Philippines, Malaysia, Singapore, Thailand, and South Korea). Using daily data for the period 2000 to...