Misspecification Preferred: The Sensitivity of Inefficiency Rankings

Ruggiero (European Journal of Operational Research 115, 555–563. 1999) compared the two popular parametric frontier methods for cross-sectional data—the stochastic frontier and the corrected OLS—in a simulation study. He demonstrated that the inefficiency ranking accuracy of the established stochastic frontier is uniformly inferior to that of the misspecified Corrected OLS (COLS) (which lacks an error term). The reason for his result remains unclear, however. In this paper, a more extensive simulation study is therefore conducted to find out whether the superiority of COLS is simply due to small sample sizes or to poor performance of the inefficiency level estimator.JEL Classification: C1,C2,C5     

Problems with detecting assumed mediation using the hierarchical multiple regression strategy

In human resource management (HRM) and allied fields (e.g., organizational behavior, management, and industrial and organizational psychology), tests of mediation are frequently conducted using the hierarchical multiple regression (HMR) strategy of Baron and Kenny [Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51, 1173–1182]. Although previous research has identified a number of serious problems with this approach, the present study adds to the literature by identifying yet additional problems with its use in inferring the existence of mediation. Using a statistical simulation, we found that certain patterns of correlation coefficients guarantee inferences about mediation, whereas other patterns preclude such inferences. On the basis of various analyses including logistic regression and inspection of three-dimensional plots, we identified patterns of correlation coefficients needed to satisfy Baron and Kenny's [Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51, 1173–1182] conditions for inferring mediation. The same patterns have no necessary relation to actual causal connections among variables in mediation models. Moreover, as a consequence of the failure of the HMR strategy to detect mediating effects, many instances of actual mediation in HRM and allied fields may have gone undetected. In view of the foregoing, we conclude that the HMR strategy should no longer be used in testing for mediation.     

Are regulations the answer for emerging stock markets? Evidence from the Czech Republic and Poland

Does the emergence of a stock market require a well-developed legal and/or regulatory system? Although historical work by Neal and Davis [Neal, L., & Davis, L. (2005). The evolution of the rules and regulations of the first emerging markets: The London, New York, and Paris stock exchanges, 1792–1914. Quarterly Review of Economics and Finance, 45, 296–311] and Stringham [Stringham, E. (2003). The extralegal development of securities trading in seventeenth century Amsterdam. Quarterly Review of Economics and Finance, 43, 321–344] suggests that securities markets have successfully developed with little government oversight, numerous authors [including Black, B. (2001). The legal and institutional preconditions for strong securities markets. University of California Law Angeles Law Review, 48, 781–855; Coffee, J. (1999). Privatization and corporate governance: The lessons from securities market failure. Journal of Corporation Law, 25, 1–39; Frye, T. (2000). Brokers and bureaucrats: Building market institutions in Russia. Ann Arbor: University of Michigan Press; Glaeser, E., Johnson, S., & Shleifer, A. (2001). Coase versus the Coasians. Quarterly Journal of Economics, 116, 853–899; Mlčoch, L. (2000). Restructuring of property rights: An institutional view. In L. Mlčoch et al. (Eds.), Economic and Social Changes in Czech Society After 1989. Prague: The Karolinum Press; Pistor, K. (2001). Law as a determinant for equity market development – the experience of transition economies. In Peter Murrell (Ed.), The Value of Law in Transition Economies (pp. 249–287). Ann Arbor: Michigan University Press; Stiglitz, J. (1999). Whither reform. Ten years of the transition. Keynote Address, Annual Bank Conference on Development Economics, Washington, DC, April 28–30, 1999; Zhang, X. (2006). Financial market governance in developing countries: Getting the political underpinnings right. Journal of Developing Societies, 2, 169–196] argue that the Czech Republic and other Eastern European governments need more regulation for their newly created stock markets. They maintain that the Warsaw Stock Exchange, which is seen as more regulated, has outperformed the Prague Stock Exchange which is seen as largely unregulated. Thus increased regulations are a key to increased performance. This article, however, maintains that the evidence from the Czech experience has been misinterpreted. This article provides an in depth case study of the Czech stock market and finds that (a) Czech capital markets have been hindered by government intervention from their beginning, (b) that the evidence on Poland's superior performance is not as strong as suggested, and (c) that Czech regulators seem to be unqualified, lack the proper incentives, and are unlikely to benefit the market. Under these circumstances it appears that Neal and Davis (2005:311) are correct that increased government involvement is unlikely to improve the situation.     

Increasing human and social capital by applying job embeddedness theory

Most modern lives are complicated. When employees feel that their organization values the complexity of their entire lives and tries to do something about making it a little easier for them to balance all the conflicting demands, the employees tend to be more productive and stay with those organizations longer. Job embeddedness captures some of this complexity by measuring both the on-the-job and off-the-job components that most contribute to a person's staying. Research evidence as well as ample anecdotal evidence (discussed here and other places) supports the value of using the job embeddedness framework for developing a world-class retention strategy based on corporate strengths and employee preferences.To execute effectively their corporate strategy, different organizations require different knowledge, skills and abilities from their people. And because of occupational, geographic, demographic or other differences, these people will have needs that are different from other organizations. For that reason, the retention program of the week from international consultants won’t always work. Instead, organizations need to carefully assess the needs/desires of their unique employee base. Then, these organizations need to determine which of these needs/desires they can address in a cost effective fashion (confer more benefits than the cost of the program). Many times this requires an investment that will pay off over a longer term – not just a quarter or even year. Put differently, executives will need to carefully understand the fully loaded costs of turnover (loss of tacit knowledge, reduced customer service, slowed production, lost contracts, lack of internal candidates to lead the organization in the future, etc., in addition to the obvious costs like recruiting, selecting and training new people). Then, these executives need to recognize the expected benefits of various retention practices. Only then can leaders make informed decisions about strategic investments in human and social capital.

Selected bibliography

A number of articles have influenced our thinking about the importance of connecting employee retention strategies to business strategies:

• R. W. Beatty, M. A. Huselid, and C. E. Schneier. “New HR Metrics: Scoring on the Business Scorecard,” Organizational Dynamics, 2003, 32 (2), 107–121.

• Bradach. “Organizational Alignment: The 7-S Model,” Harvard Business Review, 1998.

• J. Pfeffer. “Producing Sustainable Competitive Advantage Through the Effective Management of People,” Academy of Management Executive, 1995 (9), 1–13.

• C. J. Collins, and K. D. Clark. “Strategic Human Resources Practices and Top Management Team Social Networks: An Examination of the Role of HR Practices in Creating Organizational Competitive Advantage,” Academy of Management Journal, 2003, 46, 740–752.

The theoretical development and empirical support for the Unfolding Model of turnover are captured in the following articles:

• T. Lee, and T. Mitchell. “An Alternative Approach: The Unfolding Model of Voluntary Employee Turnover,” Academy of Management Review, 1994, 19, 57–89.

• B. Holtom, T. Mitchell, T. Lee, and E.Inderrieden. “Shocks as Causes of Turnover: What They Are and How Organizations Can Manage Them,” Human Resource Management, 2005, 44(3), 337–352.

The development of job embeddedness theory is captured in the following articles:

• T. Mitchell, B. Holtom, T. Lee, C. Sablynski, and M. Erez. “Why People Stay: Using Job Embeddedness to Predict Voluntary Turnover,” Academy of Management Journal, 2001, 44, 1102–1121.

• T. Mitchell, B. Holtom, and T. Lee. “How To Keep Your Best employees: The Development Of An Effective Retention Policy,” Academy of Management Executive, 2001, 15(4), 96–108.

• B. Holtom, and E. Inderrieden. “Integrating the Unfolding Model and Job Embeddedness To Better Understand Voluntary Turnover,” Journal of Managerial Issues, in press.

• D.G. Allen. “Do Organizational Socialization Tactics Influence Newcomer Embeddedness and Turnover?” Journal of Management, 2006, 32, 237–257.

Executive SummaryEmployee turnover is costly to organizations. Some of the costs are obvious (e.g., recruiting, selecting, and training expenses) and others are not so obvious (e.g., diminished customer service ability, lack of continuity on key projects, and loss of future leadership talent). Understanding the value inherent in attracting and keeping excellent employees is the first step toward investing systematically to build the human and social capital in an organization. The second step is to identify retention practices that align with the organization's strategy and culture. Through extensive research, we have developed a framework for creating this alignment. We call this theory job embeddedness. Across multiple industries, we have found that job embeddedness is a stronger predictor of important organizational outcomes, such as employee attendance, retention and performance than the best, well-known and accepted psychological explanations (e.g., job satisfaction and organizational commitment). The third step is to implement the ideas. Throughout this article we discuss examples from the Fortune 100 Best Companies to Work For and many others to demonstrate how job embeddedness theory can be used to build human and social capital by increasing employee retention.     

Restricted houseswapping games

Restricted houseswapping games (RHGs) are a generalization of ‘one-sided matching games’, in which we specify a class II* of ‘allowable’ simple trading cycles. The cores of such games may be empty. Given II*, all possible closed RHGs have non-empty cores of II* is ‘strongly balanced’. Examples include the one-sided matching markets (^{Shapley and Scarf. Journal of Mathematical Economics 1974. 1. 23–37}. ^{Tijs et al., OR Spektrum 1984, 6, 119–123}; ^{Quinzii, International Journal of Game Theory 1984, 13, 41–60}) and the two-sided matching markets (^{Gale and Shapley. American Mathematical Monthly 1962. 69, 9–16}; ^{Shapley and Shubik, International Journal of Game Theory 1972, 1, 111–130}: and ^{Demange and Gale Econometrica 1985, 53, 873–888}).We then consider the subclass of RHGs in which there is no transferable resource. In this case, a weaker condition on II*, called ‘weak balancedness’, is sufficient to guarantee core non-emptiness. In addition, if II* is not weakly balanced, then there exists a preference profile such that the strict core of the resultant game is empty.Several other examples are given of II* that are (a) strongly balanced: (b) weakly balanced but not strongly balanced: and (c) not even weakly balanced.Finally, we discuss the issues of equilibrium definition, existence, and core-equilibrium allocation equivalence in RHGs.     

On the structure of Pareto optimal cake partitions

We study Pareto optimal partitions of a “cake” among n players. Each player uses a countably additive non-atomic probability measure to evaluate the size of pieces of cake. We present two geometric pictures appropriate for this study and consider the connection between these pictures and the maximization of convex combinations of measures, which we studied in Barbanel and Zwicker [Barbanel, J.B., Zwicker, W., 1997. Two applications of a theorem of Dvoretsky, Wald, and Wolfovitz to cake division. Theory and Decision 43, 203–207].     

A generalisation of Gumbel's bivariate logistic distribution

Summary The bivariate distributionF(x, y)=1/[1+exp(–x)+exp(–y)] was examined byGumbel. We have generalised this expression by raising it to an arbitarary power. Such a distribution may occur as a mixture of bivariate extreme-value distribution. As well as giving its basic properties, we have paid special attention to measures of correlation alternative to the product-moment, namely, Kendall's and Spearman's rank correlations and the product-moment correlation calculated after transforming the marginal distributions into Normal ones. An application to the multifactorial model of disease transmission is outlined.     

Multiple equilibria in two-sector monetary economies: An interplay between preferences and the timing for money

In this paper, we study the occurrence of local indeterminacy in two-sector monetary economies. We consider a general MIUF model with two alternative timings in monetary payments: the Cash-In-Advance timing, in which the cash available to buy goods is money in the consumers’ hands after they leave the bond market but before they enter the goods market, and the Cash-After-the-Market timing, in which agents hold money for transactions after leaving the goods market. We consider three standard specifications of preferences: the additively separable formulation, the Greenwood–Hercovitz–Huffman (GHH) (Greenwood et al., 1988) formulation and the King–Plosser–Rebelo (KPR) (King et al., 1988) formulation. First, we show that for all the three types of preferences, local indeterminacy occurs under the CIA timing with a low enough interest rate elasticity of money demand. Second, we show that with the CAM timing, although determinacy always holds under separable preferences, local indeterminacy can occur with GHH and KPR preferences. We thus prove that compared to aggregate models, two-sector models provide new rooms for local indeterminacy when non-separable standard preferences are considered.     

Forecasting bond yields in the Brazilian fixed income market

This paper studies the predictive ability of a variety of models in forecasting the yield curve for the Brazilian fixed income market. We compare affine term structure models with a variation of the Nelson–Siegel exponential framework developed by Diebold and Li [Diebold, F., & Li, C. (2006). Forecasting the Term Structure of Government Yields. Journal of Econometrics, 130, 337–364]. Empirical results suggest that forecasts made with the latter methodology are superior, and appear to be more accurate at long horizons than other different benchmark forecasts. These results are important for policy-makers, as well as for portfolio and risk managers. Further research could study the predictive ability of such models in other emerging markets.     

Measuring and testing Granger causality over the spectrum: An application to European production expectation surveys

Decomposing Granger causality over the spectrum allows us to disentangle potentially different Granger causality relationships over different frequencies. This may yield new and complementary insights compared to traditional versions of Granger causality. In this paper, we compare two existing approaches in the frequency domain, proposed originally by Pierce [Pierce, D. A. (1979). R-squared measures for time series. Journal of the American Statistical Association, 74, 901–910] and Geweke [Geweke, J. (1982). Measurement of linear dependence and feedback between multiple time series. Journal of the American Statistical Association, 77, 304–324], and introduce a new testing procedure for the Pierce spectral Granger causality measure. To provide insights into the relative performance of this test, we study its power properties by means of Monte Carlo simulations. In addition, we apply the methodology in the context of the predictive value of the European production expectation surveys. This predictive content is found to vary widely with the frequency considered, illustrating the usefulness of not restricting oneself to a single overall test statistic.     

E-Leadership and Virtual Teams

In this paper we have identified some key challenges for E-leaders of virtual teams. Among the most salient of these are the following:

• The difficulty of keeping tight and loose controls on intermediate progress toward goals

• Promoting close cooperation among teams and team members in order to integrate deliverables

• Encouraging and recognizing emergent leaders in virtual teams

• Establishing explicit processes for archiving important written documentation

• Establishing and maintaining norms and procedures early in a team’s formation and development

• Establishing proper boundaries between home and work

Virtual team environments magnify the differences between good and bad projects, organizations, teams, and leaders. The nature of such projects is that there is little tolerance for ineffective leadership. There are some specific issues and techniques for mitigating the negative effects of more dispersed employees, but these are merely extensions of good leadership—they cannot make up for the lack of it.

SELECTED BIBLIOGRAPHY

An excellent reference for research on teams is M. E. Shaw, R. M. McIntyre, and E. Salas, “Measuring and Managing for Team Performance: Emerging Principles from Complex Environments,” in R. A. Guzzo and E. Salas, eds., Team Effectiveness and Decision Making in Organizations (San Francisco: Jossey-Bass, 1995). For a fuller discussion of teleworking and performance-management issues in virtual teams, see W. F. Cascio, “Managing a Virtual Workplace,” Academy of Management Executive, 2000, 14(3), 81–90, and also C. Joinson, “Managing Virtual Teams,” HRMagazine, June 2002, 69–73. Several sources discuss the issue of trust in virtual teams: D. Coutu, “Trust in Virtual Teams,” Harvard Business Review, May–June 1998, 20–21; S. L. Jarvenpaa, K. Knoll, and D. E. Leidner, “Is Anybody Out There? Antecedents of Trust in Global Virtual Teams,” Journal of Management Information Systems, 1998, 14(4), 29–64. See also Knoll and Jarvenpaa, “Working Together in Global Virtual Teams,” in M. Igbaria and M. Tan, eds., The Virtual Workplace (Hershey, PA: Idea Group Publishing, 1998).Estimates of the number of teleworkers vary. For examples, see Gartner Group, Report R-06-6639, November 18, 1998, and also Telework America survey, news release, October 23, 2001. We learned about CPP’s approach to managing virtual work arrangements through David Krantz, personal communication, August 20, 2002, Palo Alto, CA.There are several excellent references on emergent leaders. For example, see G. Lumsden and D. Lumsden, Communicating in Groups and Teams: Sharing Leadership (Belmont, CA: Wadsworth, 1993); Lumsden and Lumsden, Groups: Theory and Experience, 4th ed. (Boston: Houghton, 1993); R. W. Napier and M. K. Gershenfeld, Groups: Theory and Experience, 4th ed. (Boston: Houghton, 1989); and M. E. Shaw, Group Dynamics: The Psychology of Small Group Behavior, 3rd ed. (New York: McGraw-Hill, 1981).An excellent source for e-mail style is D. Angell and B. Heslop, The Elements of E-mail Style: Communicate Effectively via Electronic Mail (Reading, MA: Addison-Wesley Publishing Company, 1994). To read more on the growing demand for flexible work arrangements, see “The New World of Work: Flexibility is the Watchword,” Business Week, 10 January 2000, 36.For more on individualism and collectivism, see H. C. Triandis, “Cross-cultural Industrial and Organizational Psychology,” in H. C. Triandis, M. D. Dunnette, and L. M. Hough, eds., Handbook of Industrial and Organizational Psychology, 2nd ed., vol. 4 (Palo Alto, CA: Consulting Psychologists Press, 1994, 103–172).Executive SummaryAs the wired world brings us all closer together, at the same time as we are separated by time and distance, leadership in virtual teams becomes ever more important. Information technology makes it possible to build far-flung networks of organizational contributors, although unique leadership challenges accompany their formation and operation. This paper describes the growth of virtual teams, the various forms they assume, the kinds of information and support they need to function effectively, and the leadership challenges inherent in each form. We then provide workable, practical solutions to each of the leadership challenges identified.     

An alternative approach to housing market segmentation using hedonic price data

Much empirical research has been devoted to housing market segmentation and the implications for the application of the Hedonic Price Model. Market segmentation is demonstrated empirically in (J. Urban Econ., 3:2, 146–166 (1976); J. Urban Econ., 7:1, 102–108 (1980); Rev. Econ. Statist., 66:3, 404–406 (1974)). There appears to be theoretical evidence (J. Pol. Econ., 82:1, 34–55 (1974)) that such empirical efforts may have been less than adequate. Unfortunately, the empirical applications of Rosen's model (J. Environ. Econ. Manag., 5, 81–102 (1978); J. Urban Econ., 5, 3, 357–369 (1978)) do not seem to effectively account for the complexity of the factors which cause multiple equilibria (market segmentation). This paper demonstrates empirically that market segments can be defined along more dimensions than hitherto have been included in any analysis.     

Modeling tourism: A fully identified VECM approach

System-based cointegration methods have become popular tools for economic analysis and forecasting. However, the identification of structural relationships is often problematic. Using a theory-directed sequential reduction method suggested by Hall, Henry and Greenslade [Hall, S. G., Henry, S., & Greenslade, J. (2002). On the identification of cointegrated systems in small samples: A modelling strategy with an application to UK wages and prices. Journal of Economic Dynamics and Control, 26, 1517–1537], we estimate a vector error correction model of Hawaii tourism, where both demand and supply-side influences are important. We identify reasonable long-run equilibrium relationships, and Diebold–Mariano tests for forecast accuracy demonstrate satisfactory forecasting performance.     

Evaluation of supplier capability and performance: A method for supply base reduction

Development of partnership with suppliers is widely recognised today as a potent tool for supply chain improvement. To develop an effective partnership, it is necessary to have a small supply base and an effort to reduce the supply base to a manageable level. Despite its overwhelming importance, models of supply base reduction are rare. Supplier sorting methods, used for pre-selection of suppliers and sometimes seen as methods for supply base reduction, have limitations ranging from (1) requirement of an exhaustive database of historical information (case-based reasoning), (2) inability to predefine the number of elements in a cluster (cluster analysis) and (3) inability to identify suppliers who are both highly capable as well as high performers (data envelopment analysis). In the present work, we develop a systematic framework for carrying out the supply base reduction process. The study assumes two important dimensions of suppliers—performance and capability. Performance of a supplier represents short-term effects on the achievement of supply chain objectives while supplier capability indicates long-term effects. Many of the performance and capability factors are imprecise in nature. In order to account for the imprecision involved in numerous subjective characteristics of suppliers, we use fuzzy set approach to measure the imprecision of these factors and rank a potential list of suppliers against their performance and capability. We then display their ranks in a ‘capability–performance matrix’ that helps a decision maker arrange the suppliers in decreasing order of preference. The desired numbers of suppliers are finally selected on the basis of this ordered list. The suggested framework will be of immense help to the practising managers in reducing the supply base—a prerequisite for building a strong supplier partnership and developing an effective supply chain.     

Is econometrics useful for private policy making? A case study of replacement policy at an auto rental company

The goal of this paper is to illustrate the potential usefulness of econometrics as a tool to assist private policy makers. We provide a case study and detailed econometric analysis of the automobile replacement policy adopted by a large car rental company. Unlike public policy making–where the benefits from using econometric models and “science-based” approaches to policy making are hard to quantify because the outcomes of interest are typically subjective quantities such as “social welfare”–in the case of firms there is an objective, easily quantifiable criterion for judging whether policy A is better than policy B: profits. We introduce and estimate an econometric model of the rental histories of individual cars in the company’s fleet. Via stochastic simulations, we show that the model provides a good approximation to the company’s actual operations. In particular, the econometric model is able to reproduce the extraordinarily high rates of return that the company obtains on its rental cars, with average internal rates of return between purchase and sale of approximately 50%. However, the econometric model can simulate outcomes under a range of counterfactual vehicle replacement policies. We use the econometric model to simulate the profitability of an alternative replacement policy under pessimistic assumptions about the rate maintenance costs would increase and rental rates would have to be decreased if the company were to keep its rental cars longer than it does under the status quo. Depending on the vehicle type, we find that the company’s expected discounted profits would be between 6% to over 140% higher under the suggested alternative operating strategy where vehicles are kept longer and rental rates of older vehicles are discounted to induce customers to rent them. The company found this analysis to be sufficiently convincing that it undertook an experiment to verify the predictions of the econometric model.     

Order imbalance and stock returns: Evidence from China

We investigate the relation between daily order imbalance and return in the Chinese stock markets of Shenzhen and Shanghai. Prior studies have found that daily order imbalance is predictive of subsequent returns. On the two Chinese exchanges we find the autocorrelation in order imbalances is similar to that of the New York Stock Exchange as reported by Chordia and Subrahmanyam [Chordia, T., & Subrahmanyam, A. (2004). Order imbalance and individual stock returns: Theory and evidence. Journal of Financial Economics, 72, 485–518]. We also find a strong contemporaneous relation between daily order imbalances and returns. However, we do not find evidence that order imbalances predict subsequent returns. We attribute the difference in predicative power to differences in trading mechanisms on the two exchanges and to differences in the share turnover rates.     

Planning a mature economy in the USSR

Conclusion Few of the techniques of planning we have now been considering were available to the Soviet economist during the period of intensive industrialisation; those which were available were worked out only in elementary form. In any case, the gap between the goals of the politicians and the assumptions of the economists was so great that little dialogue was possible. The politicians, and the politically-minded economists, undertook the elaboration of their own system of planning and their own ruleof-thumb methods of quantifying their goals to make them operational. In doing this, they acquired a rich fund of valuable experience about the problems of development through central planning; the lessons from this experience, both successful and unsuccessful, could save resources in other economies where central planning is being used for development. Unfortunately, it is information about formal mechanisms for planning and financial control which has until now tended to be communicated from the Eastern bloc to the developing countries, rather than a realistic account of problems and achievements. For the developing countries, the further question exists: now that the new techniques for planning are available, can they be coupled with planning for a high rate of growth in conditions of rapid social change? If so, some of the successes of Soviet-type central planning may be achieved at less cost.For previous articles in this series, see Economics of Planning, Vol. 5, 1965, No. 1–2, pp. 74–86, Vol. 6, 1966, No. 1, pp. 53–67.     

Exact and asymptotic tests for possibly non-regular hypotheses on stochastic volatility models

We study the problem of testing hypotheses on the parameters of one- and two-factor stochastic volatility models (SV), allowing for the possible presence of non-regularities such as singular moment conditions and unidentified parameters, which can lead to non-standard asymptotic distributions. We focus on the development of simulation-based exact procedures–whose level can be controlled in finite samples–as well as on large-sample procedures which remain valid under non-regular conditions. We consider Wald-type, score-type and likelihood-ratio-type tests based on a simple moment estimator, which can be easily simulated. We also propose a C(α)-type test which is very easy to implement and exhibits relatively good size and power properties. Besides usual linear restrictions on the SV model coefficients, the problems studied include testing homoskedasticity against a SV alternative (which involves singular moment conditions under the null hypothesis) and testing the null hypothesis of one factor driving the dynamics of the volatility process against two factors (which raises identification difficulties). Three ways of implementing the tests based on alternative statistics are compared: asymptotic critical values (when available), a local Monte Carlo (or parametric bootstrap) test procedure, and a maximized Monte Carlo (MMC) procedure. The size and power properties of the proposed tests are examined in a simulation experiment. The results indicate that the C(α)-based tests (built upon the simple moment estimator available in closed form) have good size and power properties for regular hypotheses, while Monte Carlo tests are much more reliable than those based on asymptotic critical values. Further, in cases where the parametric bootstrap appears to fail (for example, in the presence of identification problems), the MMC procedure easily controls the level of the tests. Moreover, MMC-based tests exhibit relatively good power performance despite the conservative feature of the procedure. Finally, we present an application to a time series of returns on the Standard and Poor’s Composite Price Index.