Long memory in stock market volatility and the volatility-in-mean effect: The FIEGARCH-M Model

We extend the fractionally integrated exponential GARCH (FIEGARCH) model for daily stock return data with long memory in return volatility of Bollerslev and Mikkelsen (1996) by introducing a possible volatility-in-mean effect. To avoid that the long memory property of volatility carries over to returns, we consider a filtered FIEGARCH-in-mean (FIEGARCH-M) effect in the return equation. The filtering of the volatility-in-mean component thus allows the co-existence of long memory in volatility and short memory in returns. We present an application to the daily CRSP value-weighted cum-dividend stock index return series from 1926 through 2006 which documents the empirical relevance of our model. The volatility-in-mean effect is significant, and the FIEGARCH-M model outperforms the original FIEGARCH model and alternative GARCH-type specifications according to standard criteria.     

Continuous‐time models,realized volatilities,and testable distributional implications for daily stock returns

We provide an empirical framework for assessing the distributional properties of daily speculative returns within the context of the continuous‐time jump diffusion models traditionally used in asset pricing finance. Our approach builds directly on recently developed realized variation measures and non‐parametric jump detection statistics constructed from high‐frequency intra‐day data. A sequence of simple‐to‐implement moment‐based tests involving various transformations of the daily returns speak directly to the importance of different distributional features, and may serve as useful diagnostic tools in the specification of empirically more realistic continuous‐time asset pricing models. On applying the tests to the 30 individual stocks in the Dow Jones Industrial Average index, we find that it is important to allow for both time‐varying diffusive volatility, jumps, and leverage effects to satisfactorily describe the daily stock price dynamics. Copyright © 2009 John Wiley & Sons, Ltd.     

Knowledge flows through social networks in a cluster: Comparing university and industry links

Knowledge spillovers from a university to the local industry play an important role in high-technology clusters, but we know little about these spillovers. This paper examines empirically the extent of informal contacts between employees in firms and local university researchers in a wireless communications cluster. Furthermore, it analyses the features of an engineer who acquires knowledge from these informal contacts. The university–industry contacts are compared to results for informal contacts between employees in firms. The research shows that the interfirm informal contacts are more numerous than university informal contacts. Likewise, knowledge is more frequently acquired from engineers in other firms than through university–industry contacts. However, not all engineers in the cluster have informal contacts or acquire knowledge through these. Engineers who have participated in formal projects with university researchers and engineers who are educated at the local university have a higher likelihood of acquiring knowledge from informal contacts with university researchers.     

Default premia on European government debt

Default Premia on European Government Debt. — This paper addresses the question of the existence and size of a risk premium in the Eurobond market. We measure the yield difference between German government bonds and bonds issued in Deutsche Mark by several European countries. The results are regressed against macroeconomic variables supposed to be determinants of the risk of default on government debt. Our yield differences are smaller than those found between US states. However, some of our macroeconomic variables seem to be good predictors of yield differentials. A conclusion is that yield differentials partially are related to risks perceived by market participants.     

FLOWS OF THE PACIFIC: ASIAN FOREIGN EXCHANGE MARKETS THROUGH TRANQUILITY AND TURBULENCE

Using the longest data set on foreign exchange (FX) order flow to date, along with the broadest coverage of currencies to date, we examine the effect of FX order flow on exchange rates across small and large currencies, currencies with floating or fixed regimes, and across both tranquil and turbulent periods. Over our 15 years of data for 11 Asian and Australasian currencies, we find that order flow has a potentially strong impact on all exchange rates in the sample. The effect is strongest on floating exchange rates, both economically and statistically, but is sizeable also on the other exchange rates, especially during periods of turbulence. By creating a measure of regional order flow, we show that all exchange rates depreciate as flows are moved out of Asia/Australasia and into US dollars. This is true both across regimes and if their own flow is not included in the structure of the regional flow.     

Forming and Dissolving Partnerships in Cooperative Game Situations

A group of players in a cooperative game are partners (e.g., as in the form of a union or a joint ownership) if the prospects for cooperation are restricted such that cooperation with players outside the partnership requires the accept of all the partners. The formation of such partnerships through binding agreements may change the game implying that players could have incentives to manipulate a game by forming or dissolving partnerships. The present paper seeks to explore the existence of allocation rules that are immune to this type of manipulation. An allocation rule that distributes the worth of the grand coalition among players is called partnership formation‐proof if it ensures that it is never jointly profitable for any group of players to form a partnership and partnership dissolution‐proof if no group can ever profit from dissolving a partnership. The paper provides results on the existence of such allocation rules for general classes of games as well as more specific results concerning well‐known allocation rules.     

The importance of consumer multihoming (joint purchases) for market performance: Mergers and entry in media markets

Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming.     

Access price structure and entrant build-or-buy incentives in mobile markets

Journal of Regulatory Economics - We consider a market structure with three mobile providers, two of which are vertically integrated with nationwide coverage. The third provider (an entrant)...     

From the blogosphere into the parliament: The role of digital technologies in organizing social movements

In this paper, we present a process model exploring the roles played by digital technologies (DTs) in the organization of collective action (CA) of social movements (SMs) at different points in their lifecycles. The process model, which is based on an exploratory case study of the Italian Five Star Movement, relates the environmental conditions to the working logic, structure and use of DTs at three different stages of the SMs. We explain how these choices are adopted at each stage to address internal and environmental challenges and how they create further challenges to be addressed to pass to the next stage. We further explore the dynamics between the logic of connective and collective action and reflect on the growing need for structures and control. By so doing, our work addresses the need for a better understanding of the coevolution between DTs and organizational structures and of the ways in which DTs are used to mobilize people to sustain CA along the SM lifecycle.     

Resale price maintenance and restrictions on dominant firm and industry-wide adoption

We consider a model in which firms use resale price maintenance (RPM) to dampen competition. We find that even though the motive for using RPM is thus anti-competitive, market forces may limit the overall adverse impact on consumers. Indeed, we find that when there are a large number of firms in the market, consumer welfare under a laissez-faire policy might be as high or almost as high as it would be under an alternative policy in which RPM is banned. Government interventions that put an upper limit on the extent of industry-wide adoption of RPM can have adverse welfare effects in the model. We further show that proposed guidelines in the United States and Europe may come close to minimizing welfare.