Will It Spread or Not? The Effects of Social Influences and Network Topology on Innovation Diffusion

Innovation diffusion theory suggests that consumers differ concerning the number of contacts they have and the degree and the direction to which social influences determine their choice to adopt. To test the impacts of these factors on innovation diffusion, in particular the occurrence of hits and flops, a new agent‐based model for innovation diffusion is introduced. This model departs from existing percolation models by using more realistic agents (both individual preferences and social influence) and more realistic networks (scale free with cost constraints). Furthermore, it allows consumers to weight the links they have, and it allows links to be directional. In this way this agent‐based model tests the effect of VIPs who can have a relatively large impact on many consumers. Results indicate that markets with high social influence are more uncertain concerning the final success of the innovation and that it is more difficult for the innovation to take off. As consumers affect each other to adopt or not at the beginning of the diffusion, the new product has more difficulties to reach the critical mass that is necessary for the product to take off. In addition, results of the simulation experiments show under which conditions highly connected agents (VIPs) determine the final diffusion of the innovation. Although hubs are present in almost any network of consumers, their roles and their effects in different markets can be very different. Using a scale‐free network with a cut‐off parameter for the maximum number of connections a hub can have, the simulation results show that when hubs have limits to the maximum number of connections the innovation diffusion is severely hampered, and it becomes much more uncertain. However, it is found that the effect of VIPs on the diffusion curve is often overestimated. In fact when the influence of VIPs on the decision making of the consumers is strengthened compared with the influence of normal friends, the diffusion of the innovation is not substantially facilitated. It can be concluded that the importance of VIPs resides in their capacity to inform many consumers and not in a stronger persuasive power.     

Has the Internet Eliminated Regional Price Differences? Evidence from the Used Car Market

We study the effects of the Internet on regional price differences. Comparing two Dutch regions, we find that before the rise of the Internet, price differences of used cars between those regions amounted to some 11–15%, controlling for mileage, age, fuel type and engine volume. These price differences have completely disappeared after the rise of the Internet, in particular a website that allows consumers to make detailed comparisons between almost all used cars for sale in the Netherlands.     

INDIFFERENCE PRICE WITH GENERAL SEMIMARTINGALES

Using duality methods, we prove several key properties of the indifference price π for contingent claims. The underlying market model is very general and the mathematical formulation is based on a duality naturally induced by the problem. In particular, the indifference price π turns out to be a convex risk measure on the Orlicz space induced by the utility function.     

Economic consequences of intifada

In 2003 the World Bank (WB) and the International Monetary Fund (IMF) published estimates of macro-economic indicators for 2002 of the economy of Palestine. The WB used a micro-founded recursive dynamic computable general equilibrium (CGE) model, calibrated on the 1998 Social Accounting Matrix (SAM) of Palestine, to which shocks were applied, whereas the IMF based its estimates on a macro-founded income-expenditure model relying on more recent data. It turned out that there were substantial differences: the estimate by the WB of the real gross national income (at 1998 prices) was 25% less than the corresponding figure calculated by the IMF. This huge difference is not only relevant for a full understanding of the economic consequences of the intifada, but also for the size of the international community intervention. In this paper we propose our own evaluation with the help of a static CGE model, based on the 1998 SAM and the so-called intifada shock derived from data of the WB that we constructed for the analysis of some forms of emergency assistance in a previous article. It turns out that our estimates, based on an entirely different methodology, are remarkably close to those of the IMF.     

Why Do Companies Go Public? An Empirical Analysis

Using a large database of private firms in Italy, we analyze the determinants of initial public offerings (IPOs) by comparing the ex ante and ex post characteristics of IPOs with those of private firms. The likelihood of an IPO is increasing in the company's size and the industry's market-to-book ratio. Companies appear to go public not to finance future investments and growth, but to rebalance their accounts after high investment and growth. IPOs are also followed by lower cost of credit and increased turnover in control.     

Financial dollarization and systemic risks: New empirical evidence

This paper explores the persistence of financial dollarization in a group of 79 economies with different levels of development. Our main hypothesis is that a high level of domestic debt combined with default risk explains this persistence, even after a decline in inflation rates. Using the generalized method of moments (GMM) in a panel data analysis, our results show that inflation risks caused by increasing probability of default account for financial dollarization more than inflation rate itself. After the decrease in inflation rates, the foreign currency-denominated deposits remain large because of the high debt-to-GDP ratios, particularly in speculative-grade economies. High public indebtedness leads to expectations of default. Dollarization is a rational response to the future inflation associated with investors' expectations of default observed in highly indebted economies.     

Conducting Mode 2 research in HRM: A phase‐based framework

Recent studies in the field of human resource management (HRM) have highlighted that current research is mostly performed and consumed by academics, and is driven by theoretical and disciplinary concerns rather than practical ones. This debate has invoked the need to produce more Mode 2 research in the HRM field, that is, research driven by practical problems that integrate collaborative efforts by academics and practitioners. Yet, guidelines on how academics and practitioners may implement Mode 2 research remain disjointed and incomplete. Our study provides a phase‐based collaborative‐based framework for the implementation of Mode 2 research in the HRM field, in ways that both academic rigor and practical relevance are achieved. Our framework is informed by a comprehensive review of previous Mode 2 research, within and outside the HRM field. The proposed framework details four macro‐phases: the codevelopment of research questions with practitioners; the design of collaborative spaces and mechanisms; the design and management of double‐loop iterative research processes; and finally the academic and practice legitimization of Mode 2 outcomes. Our framework has the objective to support HRM researchers and practitioners, as well as relevant institutions and gatekeepers in the design, implementation, education, and assessment of Mode 2 research.     

Understanding the Racial/Ethnic Gap in Bank Account Ownership among Older Adults

The observed racial/ethnic gap in bank account ownership among older adults is substantial. We investigate socioeconomic, cognitive, and cultural barriers underling it. As additional potential barriers are accounted for, the residual gaps in financial inclusion with respect to Whites are reduced by 19% for blacks and 46% for Hispanics. We find that citizenship and “taste for privacy” play a limited role for both minority groups, while real asset ownership, health, cognitive ability, and cultural hurdles contribute substantially to the gap. For Hispanics, language barriers explain most of the gap, while neighborhood‐level socioeconomic characteristics are more salient for blacks. We also examine how the racial/ethnic composition of couples influences financial decisions. We estimate a significantly smaller residual gap between “mixed” and white couples than between minority and white couples. We provide empirical evidence suggesting that, other things equal, mixed couples are less concerned with the cultural/psychological barriers facing minority couples.     

A unified approach to systemic risk measures via acceptance sets

We specify a general methodological framework for systemic risk measures via multidimensional acceptance sets and aggregation functions. Existing systemic risk measures can usually be interpreted as the minimal amount of cash needed to secure the system after aggregating individual risks. In contrast, our approach also includes systemic risk measures that can be interpreted as the minimal amount of cash that secures the aggregated system by allocating capital to the single institutions before aggregating the individual risks. An important feature of our approach is the possibility of allocating cash according to the future state of the system (scenario‐dependent allocation). We also provide conditions that ensure monotonicity, convexity, or quasi‐convexity of our systemic risk measures.