This paper (i) proposes a simple multi-currency model of speculative foreign exchange (FX) trading, (ii) uses a natural experiment to identify the implied components of the optimal trading strategy, and (iii) proposes a new spectral inference method to strengthen the statistical evidence on the...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

Should capital cost calculation be based on a global or local market benchmark? The December 2000 redefinition of the global MSCI equity index was a natural experiment addressing this question. It is argued that this event triggered a portfolio shift (by index funds) large enough to affect the...

This paper documents how currency speculators trade when international capital flows generate predictable exchange rate movements. The redefinition of the MSCI world equity index in December 2000 provides an ideal natural experiment identifying exogenous capital flows of index tracking equity...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across ex-changes, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

Should capital cost calculations be based on a global or local market benchmark? The large-scale redefinition of the global MSCI equity index in December 2000 represents a natural experiment to address this important question. It is argued that the MSCI index revision triggered a portfolio shift...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

Since 1965, average idiosyncratic risk (IR) has never been lower than in recent years. In contrast to the high IR in the late 1990s that has drawn considerable attention in the literature, average market-model IR is 44% lower in 2013-2017 than in 1996-2000. Macroeconomic variables help explain...