Forecasting high-frequency excess stock returns via data analytics and machine learning

Borsa Istanbul introduced data analytics to present additional information about its market conditions. We examine whether this product can be utilized via various machine learning methods to predict intraday excess returns. Accordingly, these analytics provide significant prediction ratios above 50% with ideal profit ratios that can reach up to 33%. Among all the methods considered, XGBoost (logistic regression) performs better in predicting excess returns in the long-term analysis (short-term analysis). Results provide evidence for the benefits of both the analytics and the machine learning methods and raise further discussion on the semistrong market efficiency.     

How middle managers manage the political environment to achieve market goals: Insights from China's state‐owned enterprises

Research summary: Although the middle management literature has identified various bridging roles performed by middle managers in the market environment, it is relatively vague about whether and how they manage the political environment to achieve market‐related goals. In an inductive field study of four large state‐owned enterprises based in mainland Communist China, operational middle managers were found to take an active role in dealing with political actors to achieve market efficiency in their local environments, performing two distinct bridging strategies. Our field study suggests that middle managers are better equipped than their bosses (top executives) as well as their subordinates (frontline employees) to perform the bridging function between competing market and political imperatives in various local settings. Managerial summary: For firms that operate in diverse geographies, it is challenging for a handful of top executives to deal with numerous political actors. This burden could be shared with operational middle managers, who play a bridging role by drawing on their operational knowledge and local networks. Our research on middle managers who work under the scrutiny of political actors in China found that they bridge market and political ideology by conveying common features that seem legitimate to both. They also bridge market goals and political actors with personal affect. Compared to top executives and frontline employees, middle managers have unique advantages in performing these bridging functions. Firms can enhance their strategy execution ability by training middle managers in dealing with political actors in diverse contexts. Copyright © 2016 John Wiley & Sons, Ltd.     

Solvable local and stochastic volatility models: supersymmetric methods in option pricing

In this paper we provide an extensive classification of one- and two-dimensional diffusion processes which admit an exact solution to the Kolmogorov (and hence Black–Scholes) equation (in terms of hypergeometric functions). By identifying the one-dimensional solvable processes with the class of integrable superpotentials introduced recently in supersymmetric quantum mechanics, we obtain new analytical solutions. In particular, by applying supersymmetric transformations on a known solvable diffusion process (such as the Natanzon process for which the solution is given by a hypergeometric function), we obtain a hierarchy of new solutions. These solutions are given by a sum of hypergeometric functions, generalizing the results obtained in a paper by Albanese et al. (Albanese, C., Campolieti, G., Carr, P. and Lipton, A., Black–Scholes goes hypergeometric. Risk Mag., 2001, 14, 99–103). For two-dimensional processes, more precisely stochastic volatility models, the classification is achieved for a specific class called gauge-free models including the Heston model, the 3?/?2-model and the geometric Brownian model. We then present a new exact stochastic volatility model belonging to this class.     

Portfolio optimization under model uncertainty and BSDE games

We consider robust optimal portfolio problems for markets modeled by (possibly non-Markovian) Itô–Lévy processes. Mathematically, the situation can be described as a stochastic differential game, where one of the players (the agent) is trying to find the portfolio that maximizes the utility of her terminal wealth, while the other player (“the market”) is controlling some of the unknown parameters of the market (e.g., the underlying probability measure, representing a model uncertainty problem) and is trying to minimize this maximal utility of the agent. This leads to a worst case scenario control problem for the agent. In the Markovian case, such problems can be studied using the Hamilton–Jacobi–Bellman–Isaacs (HJBI) equation, but these methods do not work in the non-Markovian case. We approach the problem by transforming it into a stochastic differential game for backward stochastic differential equations (a BSDE game). Using comparison theorems for BSDEs with jumps we arrive at criteria for the solution of such games in the form of a kind of non-Markovian analogue of the HJBI equation. The results are illustrated by examples.     

Application de la théorie collective du risque à la réassurance « Excess-Loss »

Abstract

Introduction.

Les méthodes de calcul de la prime de réassurance Excess-Loss utilisées jusqu'à présent ou bien avaient un caractère purement empirique, ou bien présumaient que les écarts entre le montant des sinistres constatés et le montant des sinistres attendus se répartissent suivant la loi de Laplace-Gauss.     

Herding behaviour in the Australian loan market and its impact on bank loan quality

We examine the effect of herding behaviour on the credit quality of bank loans in Australia. We find that bank herding varies with different types of loans. It tends to be more prevalent in owner‐occupied housing loans and credit cards than other types of loans. During the global financial crisis period, herding in owner‐occupied housing loans was most pronounced due to the flight‐to‐quality phenomenon in the housing sector. Furthermore, we find that the big four banks tend to herd more than smaller and regional banks. Bank herding behaviour is countercyclical, as it is negatively related to real GDP growth and the cost of funding but is positively related to market risk. Regulatory capital requirements may also encourage herding as banks are required to hold less risk‐weighted capital for residential loans. Most importantly, bank herding is related to higher impaired assets and therefore lower loan quality. Our findings may have implications for policymakers and bank regulators.     

The market price of fiscal uncertainty

Recent fiscal interventions have raised concerns about US public debt, future distortionary tax pressure, and long-run growth potential. We explore the long-run implications of public financing policies aimed at short-run stabilization when: (i) agents are sensitive to model uncertainty, as in Hansen and Sargent (2007), and (ii) growth is endogenous, as in Romer (1990). We find that countercyclical deficit policies promoting short-run stabilization reduce the price of model uncertainty at the cost of significantly increasing the amount of long-run risk. Ultimately these tax policies depress innovation and long-run growth and may produce welfare losses.     

Overnight public information,order placement,and price discovery during the pre-opening period

This study examines the impact of corporate news announcements released overnight on price discovery during the pre-opening period in the Australian Securities Exchange. Our results suggest that the presence of these announcements increases the efficiency of indicative opening prices and that the intensity of these announcements significantly influences the aggressiveness of pre-opening orders. Using earnings announcements to compare the speed of price adjustments in response to overnight and daytime information of a homogeneous type, we find that prices respond immediately to overnight news upon the commencement of trading, whereas adjustments based on trading-hours news tend not to be instantaneous. Overall, our evidence highlights the important role of the pre-opening period in price discovery and the prospect of further enhancing this role by timing the release of public information to occur during non-trading hours.     

Rentenversicherung, Bev?lkerungsentwicklung und Kapitalmarktrendite – Eine Simulationsrechnung

How can the pension schemes be sustainably financed? This is an important issue particularly with regard to the demographic changes in many industrialized countries but also in other emerging economies such as China and India. In this paper, we use a macroeconomic model of overlapping generations to analyze the impacts of the demographic changes as well as the interactions between pension system, bond and stock markets. Furthermore, we examine how the pension system influences the distribution of wealth, consumption and saving within generations. We found out that an aging population will cause a drastic decline. Moreover, we examined which impacts on individuals?? welfare demographic changes can have for an existing pay-as-you-go pension scheme. An increase of pension age combined with a decrease of the contributions seems to be the best policy. On the other hand, increases in contributions as a result of demographic changes show the highest welfare losses.