Solving the incomplete markets model with aggregate uncertainty using explicit aggregation

We propose a method to solve models with heterogeneous agents and aggregate uncertainty. The law of motion describing aggregate behavior is obtained by explicitly aggregating the individual policy rule. The algorithm is simpler and faster than existing algorithms that rely on parameterization of the cross-sectional distribution and/or a computationally intensive simulation step. Explicit aggregation establishes a link between the individual policy rule and the set of necessary aggregate state variables, an insight that can be helpful in determining what state variables to include in other algorithms as well.     

Innovation Management Practices Compared: The Example of Project‐Based Firms*

The importance of project‐based firms is increasing, as they fulfill the growing demands for complex integrated systems and knowledge‐intensive services. While project‐based firms are generally strong in innovating their clients' systems and processes, they seem to be less successful in innovating their own products or services. The reasons behind this are the focus of this paper. The characteristics of project‐based firms are investigated, how these affect management practices for innovation projects, and the influence of these practices on project performance. Using survey data of 203 Dutch firms in the construction, engineering, information technology, and related industries, differences in characteristics between project‐based and nonproject‐based firms are identified. Project‐based firms are distinguished from nonproject‐based firms on the basis of organizational configuration, the complexity of the operational process, and the project management capabilities of the firm. Project‐based firms also differ with regard to their level of collaboration and their innovation strategy, but not in the level of autonomy. A comparison of 135 innovation projects in 96 of the firms shows that project‐based firms do not manage their innovation projects different from other firms. However, the effects of specific management practices on project performance are different, particularly the effects of planning, multidisciplinary teams and heavyweight project leaders. Differences in firm characteristics provide an explanation for the findings. The implication for the innovation management literature is that “best” practices for innovation management are firm dependent.     

Database marketing modelling for financial services using hazard rate models

This paper investigates the effectiveness of using direct mail message as an element in the communication mix of a financial retail company. The focus in this study will be on interpurchase time, i.e. duration times between the last purchase of any type of financial service by a customer at that bank and the purchasing of a personal loan.

Our findings indicate that (1) direct mail message have a very significant effect on shortening the interpurchase time, (2) the combined effect of several direct mail messages exhibits diminishing returns to scale, (3) incorporating time-varying variables in the model significantly improves model results, (4) Ownership of certain other services has a significant impact on the probability of purchase of the personal loan, and (5) conditional probability of purchase is found to increase with time elapsed since last purchase. The latter finding shows that the receny effect, known to be very important in most RRM models, may to dependent on the product category.