Waterloo economics series | 2010 | Economics

#10-001 -- Cathy Ning, Tony Wirjanto and Dinghai Xu

Modeling asymmetric volatility clusters using copulas and high frequency data (PDF)

Abstract

Volatility clustering is a well-known stylized feature of financial asset returns. In this paper, we investigate the asymmetric pattern of volatility clustering on both the stock and foreign exchange rate markets. To this end, we employ copula-based semi-parametric univariate time-series models that accommodate the clusters of both large and small volatilities in the analysis. Using daily realized volatilities of the individual company stocks, stock indices and foreign exchange rates constructed from high frequency data, we find that volatility clustering is strongly asymmetric in the sense that clusters of large volatilities tend to be much stronger than those of small volatilities. In addition, the asymmetric pattern of volatility clusters continues to be visible even when the clusters are allowed to be changing over time, and the volatility clusters themselves remain persistent even after forty days.

JEL classification

C51, G32

#10-002 -- Yuying Li and Dinghai Xu

Empirical evidence of the leverage effect in a stochastic volatility model a realized volatility approach (PDF)

Abstract

Increasing attention has been focused on the analysis of the realized volatility, which can be treated as a proxy for the true volatility. In this paper, we study the potential use of the realized volatility as a proxy in a stochastic volatility model estimation. We estimate the leveraged stochastic volatility model using the realized volatility computed from five popular methods across six sampling-frequency transaction data (from 1-min to 60-min). Availability of the realized volatility allows us to estimate the model parameters via the Maximum Likelihood Estimation (MLE) and thus avoids computational challenge in the high dimensional integration. Six stock indices are considered in the empirical investigation. We discover some consistent findings and interesting patterns from the empirical results. In general, the significant leverage effect is consistently detected at each sampling frequency. The volatility persistence becomes weaker at the lower sampling frequency. We also find that the consistent-scaling and "optimal"-weighted realized volatility method proposed by Hansen and Lunde (2005) provide relatively better performances compared to other methods considered.

JEL classification

C01, C51

#10-003 -- Dinghai Xu

A threshold stochastic volatility model with realized volatility (PDF)

Abstract

Rapid development in the computer technology has made the financial transaction data visible at an ultimate limit level. The realized volatility, as a proxy for the "true" volatility, can be constructed using the high frequency data. This paper extends a threshold stochastic volatility specification proposed in So, Li and Lam (2002) by incorporating the high frequency volatility measures. Due to the availability of the volatility time series, the parameters' estimation can be easily implemented via the standard maximum likelihood estimation (MLE) rather than using the simulated Bayesian methods. In the Monte Carlo section, several mis-specification and sensitivity experiments are conducted. The proposed methodology shows good performance according to the Monte Carlo results. In the empirical study, three stock indices are examined under the threshold stochastic volatility structure. Empirical results show that in different regimes, the returns and volatilities exhibit asymmetric behavior. In addition, this paper allows the threshold in the model to be exible and uses a sequential optimization based on MLE to search for the "optimal" threshold value. We find that the model with a flexible threshold is always preferred to the model with a fixed threshold according to the log-likelihood measure. Interestingly, the "optimal" threshold is found to be stable across different sampling realized volatility measures.

JEL classification

C01, C51

#10-004 -- Alain-Désiré Nimubona

Pollution policy and liberalization of trade in environmental goods (PDF)

Abstract

During the Doha Round at the World Trade Organization (WTO), reductions in trade barriers on environmental goods (EG) were put forward as a means of helping developed and developing countries alike deal with current environmental problems. We examine the potential effectiveness of such a strategy in countries that rely on imports for their needs in EG.We point out that liberalizing trade in EG might in fact lead to less stringent environmental regulations, resulting in an actual rise in pollution levels. We then show conditions under which the environmental effectiveness and the welfare improvement objective of this trade reform are compromised.

JEL classification

F12, F18, H23, Q58

#10-005 -- Horatiu Rus

Corruption, conflict and the management of natural resources (PDF)

Abstract

The documented link between natural resources and civil conflict is not well understood. This paper uses a political economy framework to explore the emergence of resource-based civil conflict driven by group-level discontent. Previous models of resource conflicts are premised on the idea that the desire of enrichment by appropriating resources is the driving force for insurgents. This approach, however, treats the management of the contentious resources as exogenous, while also failing to account for the grassroots dissatisfaction that is often reported to spark and/or sustain rebellions. The proposed theoretical model offers a policy-based alternative: under conditions related to the quality of governance, discontent about resource management can be instrumental in increasing the likelihood of an insurgency. While influential contributions in the literature tell the ‘resource abundance implies opportunity, implies greed-based conflict’ story, this paper focuses on relative scarcity to justify discontent and prompt a ‘grievance-based’ rebellion. The resource policy arises endogenously as the corrupt government trades off industry contributions and the cost induced by manifestations of resource-related discontent. Conservation effects of both internal pressure, in the form of civil unrest, and external pressure in the form of international trade and aid measures are analyzed in turn, and regulator corruption is shown to be an important ingredient of conflict. The last part presents some empirical evidence in support of the model’s predictions.

JEL classification

Q27, Q56, D74, H56

#10-006 -- Horatiu Rus

Renewable resources, pollution and trade in a small open economy (PDF)

Abstract

Industrial pollution often exerts negative spillovers on resource-based productive sectors. International trade creates conditions for the overexploitation of an open-access renewable resource, but also provides opportunities for separating the productive sectors spatially. The existing literature suggests that a diversified exporter of the renewable resource good tends to lose from trade due to over-depletion, while the exporter of the non-resource good gains. This paper shows that, depending on the relative damage inflicted by the two industries on the environment, it is possible that the production externality will persist and that specialization in the manufacturing/dirty good may not be the optimal choice from a welfare perspective. In addition, the resource exporter does not necessarily have to lose from trade even when specializing incompletely, due to the partially offsetting external effects.

JEL classification

Q27, Q22, Q53

#10-007 -- Horatiu Rus

Environmental depletion, governance and conflict (PDF)

Abstract

The link between natural resource dependence and internal conflict has been approached from a variety of angles in a large and growing interdisciplinary literature. While there is an expanding consensus as to what matters the most for such intra-state violence episodes, the

feasibility - discontent dichotomy still appears to characterize a disciplinary divide between economists and political scientists. This paper attempts to help bridge the gap by allowing for both intrinsic and extrinsic motivations of potential rebels. Simple non-cooperative bargaining yields a nonlinear impact of regulatory quality on the likelihood of conflict and shows that corruption and resource depletion jointly affect the outcome. The empirical analysis that follows looks at the effect of environmental depletion and government corruption on the emergence of civil conflicts using a large panel dataset. Resource depletion, the quality of governance and their interaction are found to be significant determinants of civil conflict incidence. Results are robust to several steps taken to address potential endogeneity concerns.

JEL classification

Q27, Q56, D74, H56

#10-008 -- Jean-Paul Lam

The importance of commitment in the New Keynesian model (PDF)

Abstract

In the New Keynesian model, even if the central bank does not have an over-ambitious output target, policy under discretion leads to an inefficiency known as the stabilisation bias. In this paper, using a New Keynesian model, we explore and quantify how various uncertainties such as an information lag, a cost channel and multi-period data revisions affect the size of the stabilisation bias. When an information lag is introduced in an otherwise standard New Keynesian model, we find that the size of the stabilisation bias is considerably reduced. The presence of a cost-channel in the model, on the other hand, increases the stabilisation bias significantly. Finally, multi-period revisions to output and inflation, reduces the inefficiency associated with discretionary policy.

JEL classification

E52, E58, E61

#10-009 -- Alain-Désiré Nimubona and Bernard Sinclair-Desgagne

Polluters and abaters (PDF)

Abstract

To comply with laws, regulations and social demands, polluting firms increasingly purchase the needed means from specialized suppliers. This paper analyzes this relatively recent phenomenon. We show how environmental regulation, the size of the output market, the elasticity of demand for abatement goods and services, and the fact that in-house and outsourced abatement expenses are substitutes or complements can influence a polluter's make-or-buy decision. Specific features of abatement outsourcing are highlighted, qualifications and refinements of the theory of vertical integration are then proposed, and some consequences for environmental policy are briefly discussed.

JEL classification

L23, L24, Q52

#10-010 -- Matthew Doyle and Jean-Paul Lam

Is the New Keynesian explanation of the great dis-inflation consistent with the cross country data (PDF)

Abstract

A leading explanation of long run U.S. inflation trends attributes both the fall of inflation in the 1980s and the subsequent years of low and stable inflation to well run monetary policy pinning down inflationary expectations. Most other Organisation for Economic Co-operation and Development (OECD) economies experienced a similar rise and fall of inflation, as well as subsequent low and stable inflation over the same period. This observation has been under-explored in the literature. In this paper we exploit the international dimension of the fall of inflation to investigate the hypothesis that good monetary policy is responsible for recent inflation outcomes. Our results suggest that this theory is not compatible with the cross country data.

JEL classification

E42, E50

#10-011 -- Jean Guillaume Forand

Two-party competition with persistant policies (PDF)

Abstract

This paper studies the Markov perfect equilibrium outcomes of a dynamic game of electoral competition between two policy-motivated parties. I model incumbent policy persistence: parties commit to implement a policy for their full tenure in office, and hence in any election only the opposition party renews its platform. In equilibrium, parties alternate in power and policies converge to symmetric alternations about the median voter's ideal policy. Parties' disutility from opponents' policies leads to alternations that display bounded extremism; alternations far from the median are never limits of equilibrium dynamics. Under a natural restriction on strategies, I find that robust long-run outcomes display bounded moderation; alternations close to the median are reached in equilibrium only if policy dynamics start there. I show that these results are robust to voters being forward-looking, the introduction of term limits, costly policy adjustments for incumbents, and office benefits.

JEL classification

C73, D72, D78

#10-012 -- Mikko Packalen and Tony Wirjanto

Inference about clustering and parametric assumptions in covariance matrix estimation (PDF)

Abstract

Selecting an estimator for the variance covariance matrix is an important step in hypothesis testing. From less robust to more robust, the available choices include: Eicker/White heteroskedasticity-robust standard errors, Newey and West heteroskedasticity-and-autocorrelation-robust standard errors, and cluster-robust standard errors. The rationale for using a less robust covariance matrix estimator is that tests conducted using a less robust covariance matrix estimator can have better power properties. This motivates tests that examine the appropriate level of robustness in covariance matrix estimation. We propose a new robustness testing strategy, and show that it can dramatically improve inference about the proper level of robustness in covariance matrix estimation. Our main focus is on inference about clustering although the proposed robustness testing strategy can also improve inference about parametric assumptions in covariance matrix estimation, which we demonstrate for the case of testing for heteroskedasticity. We also show why the existing clustering test and other applications of the White (1980) robustness testing approach perform poorly, which to our knowledge has not been well understood. The insight into why this existing testing approach performs poorly is also the basis for the proposed robustness testing strategy.

JEL classification

C10, C12, C13, C52

#10-013 -- Mikko Packalen

Identification and estimation of social interactions through variation in equilibrium influence (PDF)

Abstract

This paper presents a new method for estimating social interaction effects. The proposed approach is based on using network interaction structure induced variation in equilibrium influence to construct conditionally balanced interaction structures. As equilibrium influence is determined by the known interaction structure and the unknown endogenous social interaction parameter, interaction structures are constructed for different imputed values of the unknown parameter. Each constructed interaction structure is conditionally balanced in the sense that when it is combined with observations on the outcome variable to construct a new variable, the constructed variable is a valid instrumental variable for the endogenous social interaction regressor if the true and imputed parameter values are the same. Comparison of each imputed value with the associated instrumental variable estimate thus yields a confidence set estimate for the endogenous social interaction parameter as well as for other model parameters. We provide conditions for point identification and partial identification.

The contrast between the proposed and existing approaches is stark. In the existing approach instruments are constructed from observations on exogenous variables, whereas in the proposed approach instruments are constructed from observations on the outcome variable. Both approaches have advantages, and the two approaches complement one another. We demonstrate the feasibility of the proposed approach with analyses of the determinants of subjective college completion and income expectations among adolescents in the Add Health data and with Monte Carlo simulations of Erdös-Rényi and small-world networks.

JEL classification

C31, C26

#10-014 -- Jay Bhattacharya and Mikko Packalen

Opportunities and benefits as determinants of the direction of scientific research (PDF)

Abstract

Scientific research and private-sector technological innovation are different in terms of objectives, constraints, and organizational forms. For example, the for-profit objective that drives private-sector innovation is absent from much of scientific research, and individual researchers have many times more control in scientific research than in private-sector innovation. These differences and the lack of any obvious objective that would drive the direction of scientific research raise the possibility that the direction of scientific research is exogenous in the sense that it may not be influenced by factors such as the quality of research opportunities and the expected benefit from research that not only drive private-sector innovation but also in part determine the socially optimal allocation of research. Alternatively, some--yet largely unexplored--mechanisms drive also the direction of scientific research to respond to these factors. In this paper we test these two competing hypotheses of scientific research. In particular, we examine whether the composition of medical research responds to changes in disease prevalence and research opportunities. The extent of inventive activity is measured from the Medical Literature Analysis and Retrieval System Online (MEDLINE) database on 16 million biomedical publications. We match these data with data on disease prevalence. We develop and apply a method for estimating the quality of research opportunities from structural productivity parameters. Our results show that the direction of medical research responds to changes in disease prevalence and research opportunities.

JEL classification

O31, O33, I12, L65

#10-015 -- Jay Bhattacharya and Mikko Packalen

The other ex-ante moral hazard in health (PDF)

Abstract

It is well known that pooled insurance coverage can induce a form of ex-ante moral hazard: people make inefficiently low investments in self-protective activities. This paper identifies another ex-ante moral hazard that runs in the opposite direction: it causes people to choose inefficiently high levels of self-protection. This other ex-ante moral hazard arises through the impact that self-protective activities have on the reward for innovation. Lower levels of self-protection and the associated chronic conditions and behavioural patterns such as obesity, smoking, and malnutrition increase the incidence of many diseases for an individual. This increases the individual's consumption of treatments to those diseases, which increases the reward for innovation that an innovator receives. By the induced innovation hypothesis, which has broad empirical support, the increase in the reward for innovation in turn increases the rate of innovation, which benefits all consumers. As individuals do not take these positive externalities on the innovator and other consumers into account when deciding the level of self-protective activities, they each invest an inefficiently high level in self-protective activities. In the quantitative part of our analysis we show that for obesity the magnitude of this positive innovation externality roughly coincides with the magnitude of the negative Medicare-induced health insurance externality of obesity. The other ex-ante moral hazard that we identify can thus be as important as the ex-ante moral hazard that has been a central concept in health economics for decades. The quantitative finding also implies that the current Medicare-induced subsidy for obesity is approximately optimal. Thus the presence of this obesity subsidy is not a sufficient rationale for "soda taxes", "fat taxes" or other penalties on obesity.

JEL classification

I10, I18, D62, H23

#10-016 -- Shan Chen and Margaret Insley

Regime switching in stochastic models of commodity prices: an application to an optimal tree harvesting problem (PDF)

Abstract

This paper investigates whether a regime switching model of stochastic lumber prices is better for the analysis of optimal harvesting problems in forestry than a more traditional single regime model. Prices of lumber derivatives are used to calibrate a regime switching model, with each of two regimes characterized by a different mean reverting process. A single regime, mean reverting process is also calibrated. The value of a representative stand of trees and optimal harvesting prices are determined by specifying a Hamilton-Jacobi-Bellman Variational Inequality, which is solved for both pricing models using a fully implicit finite difference approach. The regime switching model is found to more closely match the behaviour of futures prices than the single regime model. In addition, analysis of a tree harvesting problem indicates significant differences in terms of land value and optimal harvest thresholds between the regime switching and single regime models.

JEL classification

C63, C61, Q23, D81

#10-017 -- Margaret Insley and Shilei Niu

On the economics of ramping rate restrictions at hydro power plants balancing profitability and environmental costs (PDF)

Abstract

This paper examines the impact of ramping rate restrictions imposed on hydro operations to protect aquatic ecosystems. A dynamic optimization model of the profit maximizing decisions of a hydro operator is solved for various restrictions on water flow, using data for a representative hydro operation in Ontario. Profits are negatively affected, but for a range of restrictions the impact is not large. Ramping restrictions cause a redistribution of hydro production over a given day, which can result in an increase in total hydro power produced. This affects the need for power from other sources with consequent environmental impacts.