Volatility‐Managed Portfolios

When is the Price of Risk High?

Managed portfolios that take less risk when volatility is high produce large alphas, substantially increase factor Sharpe ratios, and produce large utility gains for mean-variance investors. We document this for the market, value, momentum, profitability, return on equity, and investment factors in equities, as well as the currency carry trade. Volatility timing increases Sharpe ratios because changes in factor volatilities are not offset by proportional changes in expected returns. Our strategy is contrary to conventional wisdom because it takes relatively less risk in recessions and crises yet still earns high average returns. This rules out typical risk-based explanations and is a challenge to structural models of time-varying expected returns.

Nigeria being a mono-product economy, where the main export commodity is crude oil, changes in oil prices has implications for the Nigerian economy and, in particular, exchange rate movements. The latter is mostly important due to the double dilemma of being an oil exporting and oil-importing country, a situation that emerged in the last decade. The study examined the effects of oil price, external reserves and interest rate on exchange rate volatility in Nigeria using annual data covering the period 1970 to 2011. The theoretical framework of this study is based on Generalized Autoregressive Conditional Heteroskedasity modeled by Tim Bolerslev (1986) and Exponential General Autoregressive Conditional heteroskedastic modeled by Daniel Nelson (1991). These models were used to estimate the relationship between oil price changes and exchange rate. Relevant descriptive and econometric analyses were employed. The econometric tests adopted include the unit root tests, Johansen co-integration technique and the Vector Error Correction Model (VECM); the time series property examined shows that all the variables were stationary at first difference. The long run relationship among the variables was determined using the Johansen Co-integration technique while the vector correction mechanism was used to examine the speed of adjustment of the variables from the short run dynamics to the long run. It was observed that a proportionate change in oil price leads to a more than proportionate change in exchange rate volatility in Nigeria; which implies that exchange rate is susceptible to changes in oil price. The study therefore recommend that the Nigeria government should diversify from the Oil sector to other sectors of the economy so that Crude oil will no longer be the mainstay of the economy and frequent changes in crude oil price will not influence exchange rate volatility significantly in Nigeria.

The tea sector plays an important role in the Kenyan economy mainly through employment, contribution to Gross Domestic Product (GDP) and foreign exchange earnings. However, the sector faces a number of risks including but not limited to production, technological, price and market risks, legal and personal risks. Price and exchange rate volatility is one of the main sources of risk in the agribusiness sector. This paper sought to determine if foreign income, exchange rate, relative prices, price and exchange rate volatility have effects on Kenya’s black tea export demand. The study used panel data from World Bank and Central Bank of Kenya statistical bulletins for the period 1997 to 2010. Price and exchange volatility cannot be observed directly and were thus computed using Moving Average Standard Deviation (MASD) method. Sixteen major importer countries of Kenya’s tea were considered in the study. Im Peseran and Shin (IPS) unit root tests were used for testing the variables for the presence of unit roots. The study employed dynamic heterogeneous panel techniques developed by Peseran and Shin using autoregressive distributed lag (ARDL) model in the error correction form. The empirical model was estimated using pooled mean group (PMG) estimator. The study found that growth in foreign income and changes in price and exchange rate volatility were significant in the long and short run. Proportional changes in relative prices and foreign exchange rate were insignificant in the long run and short run. Key words: Price volatility, exchange rate volatility, Kenya’s black tea exports, autoregressive distributed lag (ARDL) model, pooled mean group (PMG) estimation.

What's so great about the Great Moderation?

The article analyses the influence of crisis-induced changes in economic activity on the monetary transmission mechanism in the small open economies of Czechia, Hungary, Poland, and Sweden from 2000: 1 to 2016: 5 using the Markov Switching Structural Bayesian Vector Autoregressive models. The results confirm that in countries where the exchange rate transmission channel is relatively weak (Hungary and Sweden), changes in volatilities coincide with changes in the coefficients of the monetary transmission mechanism, reducing the efficiency of a monetary policy during a crisis. The changes of the coefficients occurred in neither Poland nor Czechia, where the exchange rate pass-through was not closed completely. The results imply that in small open economies, public authorities’ efforts to sustain exchange rate pass-through may critically affect their ability to retain monetary control during a crisis.

A growing line of research makes use of structural changes and different volatility regimes found in the data in a constructive manner to improve the identification of structural parameters in structural vector autoregressions (SVARs). A standard assumption made in the literature is that the reduced form unconditional error covariance matrix varies while the structural parameters remain constant. Under this hypothesis, it is possible to identify the SVAR without needing to resort to additional restrictions. With macroeconomic data, the assumption that the transmission mechanism of the shocks does not vary across volatility regimes is debatable. We derive novel necessary and sufficient rank conditions for local identification of SVARs, where both the error covariance matrix and the structural parameters are allowed to change across volatility regimes. Our approach generalizes the existing literature on ‘identification through changes in volatility’ to a broader framework and opens up interesting possibilities for practitioners. An empirical illustration focuses on a small monetary policy SVAR of the US economy and suggests that monetary policy has become more effective at stabilizing the economy since the 1980s.

Can Market Regimes Really be Timed with Historical Volatility?

Volatility forecasting of crude oil futures market: Which structural change-based HAR models have better performance?

The Chicago Mercantile Exchange reduced the size of its S&P 500 futures contract when it reduced the multiplier from 500 to 250 and increased the minimum tick from 0.05 to 0.10 on November 3, 1997. This is a rare major change in a very successful contract's specifications. We analyze effects of this change on liquidity and market dynamics in both a univariate and a multivariate context. The main contribution of this study is the use of multiple intervention analysis with various dynamic response functions to examine the effects of the split while taking into account several other major market events surrounding it. A multivariate analysis is also used to test the impact of the split using a structural model of liquidity and market dynamics. Empirical findings offer limited support for the hypotheses that smaller contract size resulted in smoother trading, and that more public customers trade the S&P 500 futures contract following its split. We observe a reduction in the average transaction size as well as a temporary narrowing of the bid-ask spreads, but no significant change in volatility that can be attributed to the split. We do not find any significant and lasting impact on other liquidity and market variables.

Commodity prices are volatile, and volatility itself varies over time. Changes in volatility can affect market variables by directly affecting the marginal value of storage, and by affecting a component of the total marginal cost of production, the opportunity cost of producing the commodity now rather than waiting for more price information. I examine the role of volatility in short‐run commodity market dynamics and the determinants of volatility itself. I develop a structural model of inventories, spot, and futures prices that explicitly accounts for volatility, and estimate it using daily and weekly data for the petroleum complex: crude oil, heating oil, and gasoline. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:1029–1047, 2004

Optimal Factor Strategy in FX Markets

We investigate how the relation between gold prices and the U.S. Dollar has been affected by the recent turmoil in financial markets. We use spot prices of gold and spot bilateral exchange rates against the Euro and the British Pound to study the pattern of volatility spillovers. We estimate the bivariate structural GARCH models proposed by Spargoli e Zagaglia (2008) to gauge the causal relations between volatility changes in the two assets. We also apply the tests for change of co-dependence of Cappiello, Gerard and Manganelli (2005). We document the ability of gold to generate stable comovements with the Dollar exchange rate that have survived the recent phases of market disruption. Our findings also show that exogenous increases in market uncertainty have tended to produce reactions of gold prices that are more stable than those of the U.S. Dollar.

Gold and the U.S. Dollar: Tales from the Turmoil

We investigate how the relation between gold prices and the U.S. dollar has been affected by the recent turmoil in financial markets. We use spot prices of gold and spot bilateral exchange rates against the euro and the British pound to study the pattern of volatility spillovers. We estimate the bivariate structural GARCH models proposed by Spargoli and Zagaglia to gauge the causal relations between volatility changes in the two assets. We also apply the tests for change of co-dependence of Cappiello et al. to study the impact of the turmoil on the relation between gold and the U.S. dollar. We document the ability of gold to generate stable comovements with the dollar exchange rate that have survived the recent phases of market disruption. Our findings also show that exogenous increases in market uncertainty have tended to produce reactions of gold prices that are more stable than those of the U.S. dollar.