Aggregative games and oligopoly theory: short-run and long-run analysis

We compile an IO toolkit for aggregative games with positive and normative comparative statics results for asymmetric oligopoly in the short and long run. We characterize the class of aggregative Bertrand and Cournot oligopoly games, and the subset for which the aggregate is a summary statistic for consumer welfare. We close the model with a monopolistically competitive fringe for long-run analysis. Remarkably, we show strong neutrality properties in the long run across a wide range of market structures. The results elucidate aggregative games as a unifying principle in the literature on merger analysis, privatization, Stackelberg leadership, and cost shocks.     

Target price forecasts: The roles of the 52-week high price and recent investor sentiment

This paper reveals that in addition to fundamental factors, the 52-week high price and recent investor sentiment play an important role in analysts’ target price formation. Analysts’ forecasts of short-term earnings and long-term earnings growth are shown to be important explanatory variables for target prices; equally, the 52-week high price and recent investor sentiment are also shown to explain target price levels and especially target price biases. Our analysis additionally reveals that analysts place greater weight on these two non-fundamental factors in settings with greater task complexity and to some extent in those with greater resource constraints. Conversely, on balance, the results suggest that this increased reliance does not translate into an increased impact per unit of each non-fundamental factor on forecast bias. Finally, our results show that target prices are useful in predicting future stock returns beyond earnings forecasts and commonly used risk proxies. However, in an internally consistent fashion, the informativeness of target prices for future returns is significantly reduced when greater weight is placed on either the 52-week high or recent investor sentiment in the target price formation process.     

For fraud,look under ‘serious and organized crime’

ABSTRACT

The UK government’s response to fraud cannot be disentangled from its broader ‘serious and organized crime’ (SOC) strategy. In order to explore whether fraud should—in public policy, criminal justice and law enforcement terms—be seen primarily as an SOC issue, there is a need to consider questions about whether or not ‘SOC’ is a sensible object of policy-making in the first place. Several arguments in favour of an SOC policy are identified in the paper. However, the notion of an overarching SOC policy is problematic for three reasons. First, SOC is a fundamental misrepresentation of reality, which does not correspond to a real social problem. Second, SOC policy can limit the development of more problem-specific crime strategies, Third, the ‘SOC’ label can negatively transform how social problems are perceived over the long term. If fraud is to be better understood and dealt with, it may therefore be necessary to extract it from its current inclusion within wider SOC strategy.     

Options pricing under the one-dimensional jump-diffusion model using the radial basis function interpolation scheme

This paper will demonstrate how European and American option prices can be computed under the jump-diffusion model using the radial basis function (RBF) interpolation scheme. The RBF interpolation scheme is demonstrated by solving an option pricing formula, a one-dimensional partial integro-differential equation (PIDE). We select the cubic spline radial basis function and adopt a simple numerical algorithm (Briani et al. in Calcolo 44:33–57, 2007) to establish a finite computational range for the improper integral of the PIDE. This algorithm reduces the truncation error of approximating the improper integral. As a result, we are able to achieve a higher approximation accuracy of the integral with the application of any quadrature. Moreover, we a numerical technique termed cubic spline factorisation (Bos and Salkauskas in J Approx Theory 51:81–88, 1987) to solve the inversion of an ill-conditioned RBF interpolant, which is a well-known research problem in the RBF field. Finally, our numerical experiments show that in the European case, our RBF-interpolation solution is second-order accurate for spatial variables, while in the American case, it is second-order accurate for spatial variables and first-order accurate for time variables.     

Supporting ALARP decision making by cost benefit analysis and multiattribute utility theory

Current guidance in the UK and elsewhere indicate upper and target risk limits for the operation of nuclear plant in terms of individual risk per annum. ‘As low as reasonably practicable’ (ALARP) arguments are used to justify the acceptance or rejection of policies that lead to risk changes between these limits. The suitability of cost‐benefit analysis (CBA) and multiattribute utility theory (MAUT) are assessed for performing ALARP (‘as low as reasonably possible’) assessments, in particular within the nuclear industry. Four problems stand out in current CBA applications to ALARP, concerning the determination of prices of safety gains or detriments, the valuation of group and individual risk, calculations using ‘disproportionality’, and the use of discounting to trade‐off risks through time. This last point has received less attention in the past but is important because of the growing interest in risk‐informed regulation in which policies extend over several timeframes and distribute the risk unevenly over these, or in policies that lead to a nonuniform risk within a single timeframe (such as maintenance policies). The problems associated with giving quantitative support to such decisions are discussed. It is argued that multiattribute utility methods (MAUT) provide an alternative methodology to CBA which enable the four problems described above to be addressed in a more satisfactory way. Through sensitivity analysis MAUT can address the perceptions of all stakeholder groups, facilitating constructive discussion and elucidating the key points of disagreement. It is also argued that by being explicitly subjective it provides an open, auditable and clear analysis in contrast to the illusory objectivity of CBA. CBA seeks to justify a decision by using a common basis for weights (prices), while MAUT recognizes that different parties may want to give different valuations. It then allows the analyst to explore the ways in which different parties might (or might not) come to the same conclusion even when weighting items differently.     

A longitudinal ethnographic study of night‐freight pilots

This paper records the lived reality of night‐freight operations at a UK‐registered airline. Observations were made over an 18‐month period. The paper answers calls for more research into the working and living conditions of night‐freight pilots. Pilots perceived numerous issues. These included cultural cleavage, terms and conditions, roster instability and the impact of night flying on physical and psychological health. Some issues (volatile rosters and deep first nights, for example) had the potential to increase operational risk. Two sub‐cultures were identified within the airline: the quality‐of‐working‐life sub‐culture and competitiveness and corporate survival sub‐culture. A ‘paradox of control’ was observed. While pilots controlled the aircraft in flight, their patterns and conditions of work were decided by roster managers, crewing officers and other office‐based technocrats. Technocrats’ directive power was resented by some pilots. Some claimed that technocrats did not understand the lived reality of the line, resulting in ‘uninformed’ decisions that augmented operational risk. The study involved a single airline. No claims are made for the generalisability of the findings. More studies are required.     

Mean-reversion properties of implied volatilities

In this paper, we present a new stylized fact for options whose underlying asset is a stock index. Extracting implied volatility time series from call and put options on the Deutscher Aktien index (DAX) and financial times stock exchange index (FTSE), we show that the persistence of these volatilities depends on the moneyness of the options used for its computation. Using a functional autoregressive model, we show that this effect is statistically significant. Surprisingly, we show that the diffusion-based stochastic volatility models are not consistent with this stylized fact. Finally, we argue that adding jumps to a diffusion-based volatility model help recovering this volatility pattern. This suggests that the persistence of implied volatilities can be related to the tails of the underlying volatility process: this corroborates the intuition that the liquidity of the options across moneynesses introduces an additional risk factor to the one usually considered.     

Female participation in African labor markets: The role of information and communication technologies

This article investigates the effects of information and communication technologies (ICT) on female labor force participation in a sample of 48 African countries. We specify and estimate linear regression and dynamic panel data models with fixed effects (FE) and system-generalized method of moments (SYS-GMM) estimation over the period 2001–2017. The three main results are that ICT use (mobile phone and internet) significantly stimulates female labor force participation in Africa; this effect is enhanced by financial development and female education; the effect of ICT on female employment in Africa is strongest in the industrial sector. These results remain robust to the provision of social, cultural, and institutional variables.