A comparison of pricing and hedging performances of equity derivatives models

This article investigates the pricing/hedging conundrum, i.e. the observation of a mismatch between derivatives models’ pricing and hedging performances, that has so far been under-emphasized as the literature tends to focus on increasingly complicated option pricing models, without adequately addressing hedging performance. Hence, we analyse the ability of the Black–Scholes, Practitioner Black–Scholes, Heston–Nandi and Heston models to Delta-hedge a set of call options on the S&P500 index and Apple stock. We extend earlier studies in that we consider the impact of asset dynamics, apply a stringent payoff replication strategy, look at the impact of moneyness at maturity and test for the robustness to the parameters’ calibration frequency and Delta-Vega hedging. The study shows that adding risk factors to a model, as stochastic volatility, should only be considered in light of the data dynamics. Even then, however, more complicated models generally fare poorly for hedging purposes. Hence, a better fit of a model to option prices is not a good indicator of its hedging performance, and so of its ability to describe the underlying dynamics. This can be understood for reasons of over-fitting. Those findings hint to a potentially appealing hedging-based calibration of models’ parameters, rather than the standard pricing-based one.     

For Better or worse: Organizational turnaround in New York City schools

The performance of public organizations has become a more salient issue as the popularity of accountability policies has grown. Though organizations are often defined as underperforming, little is known about the effectiveness of various strategies commonly recommended for agency turnaround. This study provides a large-N test of three common categories of turnaround mechanisms – retrenchment, repositioning, and reorganization – in nearly 300 failing New York City schools between 2008 and 2011. Models show that none of the three turnaround strategies appear to be significantly associated with improvements in core organizational performance from an administrative perspective, although repositioning appears to improve client satisfaction.     

The effect of a Durbin–Watson pretest on confidence intervals in regression

Consider a linear regression model and suppose that our aim is to find a confidence interval for a specified linear combination of the regression parameters. In practice, it is common to perform a Durbin–Watson pretest of the null hypothesis of zero first‐order autocorrelation of the random errors against the alternative hypothesis of positive first‐order autocorrelation. If this null hypothesis is accepted then the confidence interval centered on the ordinary least squares estimator is used; otherwise the confidence interval centered on the feasible generalized least squares estimator is used. For any given design matrix and parameter of interest, we compare the confidence interval resulting from this two‐stage procedure and the confidence interval that is always centered on the feasible generalized least squares estimator, as follows. First, we compare the coverage probability functions of these confidence intervals. Second, we compute the scaled expected length of the confidence interval resulting from the two‐stage procedure, where the scaling is with respect to the expected length of the confidence interval centered on the feasible generalized least squares estimator, with the same minimum coverage probability. These comparisons are used to choose the better confidence interval, prior to any examination of the observed response vector.     

Trent J. MacDonald,The Political Economy of Non-Territorial Exit: Cryptosecession. Northampton: Edward Elgar, 2019. x + 233 pages. USD 125.00 (hardback)

The Review of Austrian Economics -     

HARSH NORMS AND SCREENING FOR LOYALTY

Norms that restrict choice sets or impose otherwise harsh requirements would seem to act as barriers to group formation by raising the costs of adherence to potential and continuing members. Contrary to that intuition, one observes a broad range of group norms in the real world that impose large costs on group members. Iannaccone provides a rationale for harsh norms as a mechanism to reduce free‐riding in supplying a club good. This paper proposes a new rationalization for harsh group norms as a mechanism under which harsh norms serve to screen out disloyal members, providing what is essentially a technology for measuring loyalty in environments where group leaders cannot reliably measure group members' loyalty. The model demonstrates that loyalty can be signalled through acts that are seemingly irrelevant to the group's core objectives and identity.     

An empirical study of credit shock transmission in a small open economy

In this paper, we identify and estimate the dynamic effects of foreign (US) and national (Canadian) credit shocks in a small open economy. We use standard credit spreads as proxies to the external finance premium. Our first result suggests that the US and Canadian credit spreads contain substantial forecasting power for several measures of the Canadian real economic activity, especially during the recent financial crisis and its aftermath. Secondly, an adverse US credit shock generates a significant and persistent economic slowdown in Canada: the national external finance premium rises immediately while interest rates, credit aggregates, output and employment indicators decline. Variance decomposition reveals that credit shocks have a sizeable effect on real activity measures, leading indicators and credit spreads. Yet, the unexpected shocks in domestic credit spreads are not able to generate any significant dynamic response of the real activity once we control for the US credit market conditions.     

A JIT-type stocking system for hospital pharmacies: the stockless method

During the past few years, hospitals have been actively evaluating the use of newer-type stocking systems for their pharmacies. While "stockless," a just-in-time (JIT) variation, appears to be emerging as perhaps the most promising method, it is far from being accepted as the industry standard. Because of growing concern for health care reform, with its cost containment component, it may well be anticipated that both the pace and profoundness of these efforts will continue to intensify.     

The Structure of Sprawl: Identifying and Characterizing Employment Centers in Polycentric Metropolitan Areas

This paper applies a consistent framework to four comparably sized metropolitan areas to identify and characterize their employment centers. Employment centers are identified as places that exceed a threshold employment density and a threshold employment level. They are also characterized as specializing on the basis of location quotient analysis. We find clear evidence of specialization in every employment center in the four metropolitan areas studied. Our interpretation is that what we are observing is a systematic change in metropolitan structure rather than a random sprawling of firms. We also find some evidence that the size distribution of employment centers follows the rank-size rule. This suggests that there is structure not only in the distribution of economic activity among the employment centers but also in their size distribution. Because less than 50 percent of metropolitan employment is within employment centers, future research should focus on understanding the more diffuse employment patterns. The rank-size rule gives some guidance as to the expected size distribution of employment throughout the metropolitan area.     

Leadership Lessons of Triangular Desire from René Girard

René Girard examined famous novels depicting something he called displaced desire, in which a follower emulates someone believed to be exemplary. These relationships can become problematic, twisted, and even contagious, as people affect desires only because someone else exhibits them. This often results in inauthentic choices and rivalry, which Girard diagnoses. In the last section of the paper are some implications for the practice and study of leadership.     

Consistency and asymptotic normality for equilibrium models with partially observed outcome variables

We derive conditions under which structural econometric models that rely on numerical computation of equilibria produce consistent and asymptotically normal parameter estimates. The conditions are weaker than those required for the application of the implicit function theory.