Dynamic spatial autoregressive models with autoregressive and heteroskedastic disturbances

We propose a new class of models specifically tailored for spatiotemporal data analysis. To this end, we generalize the spatial autoregressive model with autoregressive and heteroskedastic disturbances, that is, SARAR(1, 1), by exploiting the recent advancements in score‐driven (SD) models typically used in time series econometrics. In particular, we allow for time‐varying spatial autoregressive coefficients as well as time‐varying regressor coefficients and cross‐sectional standard deviations. We report an extensive Monte Carlo simulation study in order to investigate the finite‐sample properties of the maximum likelihood estimator for the new class of models as well as its flexibility in explaining a misspecified dynamic spatial dependence process. The new proposed class of models is found to be economically preferred by rational investors through an application to portfolio optimization.     

Understanding solicitation: Beyond the binary variable of being asked or not being asked

The identity, motivation, and experiences of philanthropists have become increasingly popular topics of study in a wide range of disciplines, yet no equivalent attention has been paid to the askers, despite research showing that almost all donations are solicited in some way. The propensity to be asked for contributions has been found to be positively related to the propensity to give, but despite the usefulness of this finding, it reinforces the suggestion that solicitation is a binary variable, such that people are either asked or they are not asked. This paper, drawing on data from in-depth interviews with 73 successful fundraisers in the UK and Canada, highlights the importance of the quality, as opposed to simply the quantity, of solicitation. Three important factors that lie behind successful “asks” are identified and discussed: First, they are made within relationships of trust rather than as a result of a transactional approach. Second, they occur as a result of fundraisers' ability to be an “honest broker” between donors and the organisations they might support. And third, they rely on the fundraisers' skills in reframing complex issues and finding alignment between the recipient organisation's needs and the philanthropic aspirations of the donor. The paper concludes with implications for practice.     

Identifying new product development best practice

New product development (NPD) practitioners are keen to benchmark NPD practices because identifying any practice that is able to more efficiently and/or effectively deliver a new product could represent the difference between success and failure. A common purpose is therefore to identify NPD best practices with the expectation that companies will manifest and sustain these to augment their NPD efforts. To help in identifying such practices, we present a framework developed from prior benchmarking studies, a Delphi methodology with leading experts, and a survey involving over 300 NPD practitioners. The uniqueness of the framework lies in its ability to distinguish NPD practice across seven dimensions: Strategy, Research, Commercialization, Process, Project Climate, Company Culture, and Metrics/Performance Measurement. The framework is also unique in that across each dimension, poor NPD practices are listed as a starting point from which to improve, alongside best practices to which companies should aspire. To further assist in continuous improvement, an audit tool is derived from the framework, suggesting investigative questions that practitioners can ask to evaluate their company's NPD efforts. We conclude with general observations about NPD practice as the continued search for NPD best practice endures.     

Hospital Financial Conditions and the Provision of Unprofitable Services

Increases in hospital financial pressure resulting from public and private payment policy may substantially reduce a hospital’s ability to provide certain services that are not well compensated or are frequently used by the uninsured. The objective of this study is to examine the impact of hospital financial condition on the provision of these unprofitable services for the insured and uninsured. Economic theory provides the conceptual underpinnings for the analysis, and a longitudinal empirical analysis is conducted for an eight-year study period. The results indicate that not-for-profit hospitals with strong financial performance provide more unprofitable services for the insured and uninsured than do not-for-profit hospitals with weaker condition. For-profit hospital provision of these services is not influenced by their financial condition and instead may reflect actions to meet community expectations or to offer a sufficiently broad service array to maintain the business of insured patients.     

Jumps in cross‐sectional rank and expected returns: a mixture model

We propose a new nonlinear time series model of expected returns based on the dynamics of the cross‐sectional rank of realized returns. We model the joint dynamics of a sharp jump in the cross‐sectional rank and the asset return by analyzing (1) the marginal probability distribution of a jump in the cross‐sectional rank within the context of a duration model, and (2) the probability distribution of the asset return conditional on a jump, for which we specify different dynamics depending upon whether or not a jump has taken place. As a result, the expected returns are generated by a mixture of normal distributions weighted by the probability of jumping. The model is estimated for the weekly returns of the constituents of the SP500 index from 1990 to 2000, and its performance is assessed in an out‐of‐sample exercise from 2001 to 2005. Based on the one‐step‐ahead forecast of the mixture model we propose a trading rule, which is evaluated according to several forecast evaluation criteria and compared to 18 alternative trading rules. We find that the proposed trading strategy is the dominant rule by providing superior risk‐adjusted mean trading returns and accurate value‐at‐risk forecasts. Copyright © 2008 John Wiley & Sons, Ltd.     

An Examination of New Product Development Best Practice

Efforts continue to identify new product development (NPD) best practices. Examples of recognized studies include those by the Product Development and Management Association's Comparative Performance Assessment Study and the American Productivity Quality Center NPD best practices study. While these studies designate practices that distinguish top‐performing companies, it is unclear whether NPD practitioners as a group (not just researchers) are knowledgeable about what represents a NPD best practice. The importance of this is that it offers insight into how NPD practitioners are translating potential NPD knowledge into actual NPD practice. In other words, are practitioners aware of and able to implement NPD best practices designated by noteworthy studies? The answer to this question ascertains a current state of the field toward understanding NPD best practice and the maturity level of various practices. Answering this question further contributes to our understanding of the diffusion of NPD best practices knowledge by NPD professionals, possibly identifying gaps between prescribed and actual practice. Beginning the empirical examination by conducting a Delphi methodology with 20 leading innovation researchers, the study examined the likely dimensions of NPD and corresponding definitions to validate the NPD practices framework originally proposed by Kahn, Barczak, and Moss. A survey was then conducted with practitioners from the United States, United Kingdom, and Ireland to gauge opinions about perceptions of the importance of different NPD dimensions, specific characteristics reflected by each of these dimensions, and the level of NPD practice maturity that these characteristics would represent. The study is therefore unique in that it relies on the opinions of NPD practitioners to see what they perceive as best practice versus prior studies where the researcher has identified and prescribed best practices. Results of the present study find that seven NPD dimensions are recommended, whereas the 2006 Kahn, Barczak, and Moss framework had suggested six dimensions. Among practitioners across the three country contexts, there is consensus on which dimensions are more important, providing evidence that NPD dimensions may be generalizable across Western contexts. Strategy was rated higher than any of the other dimensions followed by research, commercialization, and process. Project climate and metrics were perceived as the lowest in importance. The high weighting on strategy and low weighting on metrics and project climate reinforce previous best practice findings. Regarding the characteristics of each best practice dimension, practitioners appear able to distinguish what constitutes poor versus best practice, but consensus on distinguishing middle range practices are not as clear. The suggested implications of these findings are that managers should emphasize strategy when undertaking NPD efforts and consider the fit of their projects with this strategy. The results further imply that there are clearly some poor practices that managers should avoid and best practices to which managers should ascribe. For academics, the results strongly suggest a need to do a better job of diffusing NPD knowledge and research on best practices. Particular attention by academics to the issues of metrics, project climate, and company culture appears warranted.