Does Market Incompleteness Matter?

This paper argues that incompleteness of intertemporal financial markets has little effect (on welfare, prices, or consumption) in an economy with a single consumption good, provided that traders are long–lived and patient, a riskless bond is traded, shocks are transitory, and there is no aggregate risk. In an economy with aggregate risk, a similar conclusion holds, provided traders share the same CRRA utility function and the right assets are traded. Examples demonstrate that these conclusions need not hold if the wrong assets are traded or if the economy has multiple consumption goods.     

Competence and Competitive Advantage: Towards a Dynamic Model

Over the last ten years the concept of ‘competence’ has emerged as a central concept for competitive strategy. Several rich theoretical streams have contributed an extensive array of frameworks, definitions and papers using the concept. There is now a need to integrate these many contributions. Indeed, some of the frustration expressed recently by academics may be due to the large volume of conversation and the low level of integration. A concept that is considered so useful that many writers have incorporated it in their work will be of little value if it takes on different meanings for every use. If competence is to be used to explain relationships among variables and to build richer understandings of the roots of competitive advantage, then the field needs to engage in a serious conversation that attempts to focus this concept. Competence needs to be understood in a way that is faithful to its theoretical roots, allows the multiple dimensions that underpin competitive advantage to be meaningfully integrated and is specific enough that meaningful differences can emerge when used as a variable in empirical research. This paper seeks to begin a conversation toward that end by presenting a conceptualization that meets all of these requirements. The paper builds its conceptualization around satisfying the elements of a dynamic model of the relationship between competence and competitive advantage.     

Random effects and shrinkage estimation in capture-recapture models

We discuss the analysis of random effects in capture-recapture models, and outline Bayesian and frequentists approaches to their analysis. Under a normal model, random effects estimators derived from Bayesian or frequentist considerations have a common form as shrinkage estimators. We discuss some of the difficulties of analysing random effects using traditional methods, and argue that a Bayesian formulation provides a rigorous framework for dealing with these difficulties. In capture-recapture models, random effects may provide a parsimonious compromise between constant and completely time-dependent models for the parameters (e.g. survival probability). We consider application of random effects to band-recovery models, although the principles apply to more general situations, such as Cormack-Jolly-Seber models. We illustrate these ideas using a commonly analysed band recovery data set.     

On three and four vicious walkers

We establish a reflection principle for three lattice walkers and use this principle to reduce the enumeration of configurations of three vicious walkers to the enumeration of configurations of two vicious walkers. More precisely, the reflection principle leads to a bijection between three walks (L₁, L₂, L₃) such that L₂ intersects both L₁ and L₃ and three walks (L₁, L₂, L₃) such that L₁ intersects L₃. Hence we find a combinatorial interpretation of the formula for the generating function for the number of configurations of three vicious walkers, originally derived by Bousquet-Mélou by using the kernel method, and independently by Gessel by using tableaux and symmetric functions. This answers a question posed by Gessel and Bousquet-Mélou. We also find a reflection principle for four vicious walks that leads to a combinatorial interpretation of a formula derived from Gessel's theorem.     

Integration Between Business Planning and Information Systems Planning: Validating a Stage Hypothesis

This paper proposes and empirically validates a stages of growth model for the evolution of Information Systems Planning (ISP). A questionnaire survey of senior IS executives is used to gather information pertaining to the stages of growth model, which includes measurement of the nature and level of integration between business planning (BP) and ISP. The del test is used to validate empirically benchmark variables for each stage of BP-ISP integration. The results support the stages of growth model of BP-ISP integration and the benchmark variables are generally found to be successful in predicting the stage of integration.     

Bayesian model selection for join point regression with application to age-adjusted cancer rates

Summary.  The method of Bayesian model selection for join point regression models is developed. Given a set of K +1 join point models M ₀,  M ₁, …,  M _K with 0, 1, …,  K join points respec-tively, the posterior distributions of the parameters and competing models M _k are computed by Markov chain Monte Carlo simulations. The Bayes information criterion BIC is used to select the model M _k with the smallest value of BIC as the best model. Another approach based on the Bayes factor selects the model M _k with the largest posterior probability as the best model when the prior distribution of M _k is discrete uniform. Both methods are applied to analyse the observed US cancer incidence rates for some selected cancer sites. The graphs of the join point models fitted to the data are produced by using the methods proposed and compared with the method of Kim and co-workers that is based on a series of permutation tests. The analyses show that the Bayes factor is sensitive to the prior specification of the variance σ ², and that the model which is selected by BIC fits the data as well as the model that is selected by the permutation test and has the advantage of producing the posterior distribution for the join points. The Bayesian join point model and model selection method that are presented here will be integrated in the National Cancer Institute's join point software ( http://www.srab.cancer.gov/joinpoint/ ) and will be available to the public.     

Near‐Misses and Future Disaster Preparedness

Disasters garner attention when they occur, and organizations commonly extract valuable lessons from visible failures, adopting new behaviors in response. For example, the United States saw numerous security policy changes following the September 11 terrorist attacks and emergency management and shelter policy changes following Hurricane Katrina. But what about those events that occur that fall short of disaster? Research that examines prior hazard experience shows that this experience can be a mixed blessing. Prior experience can stimulate protective measures, but sometimes prior experience can deceive people into feeling an unwarranted sense of safety. This research focuses on how people interpret near‐miss experiences. We demonstrate that when near‐misses are interpreted as disasters that did not occur and thus provide the perception that the system is resilient to the hazard, people illegitimately underestimate the danger of subsequent hazardous situations and make riskier decisions. On the other hand, if near‐misses can be recognized and interpreted as disasters that almost happened and thus provide the perception that the system is vulnerable to the hazard, this will counter the basic “near‐miss” effect and encourage mitigation. In this article, we use these distinctions between resilient and vulnerable near‐misses to examine how people come to define an event as either a resilient or vulnerable near‐miss, as well as how this interpretation influences their perceptions of risk and their future preparedness behavior. Our contribution is in highlighting the critical role that people's interpretation of the prior experience has on their subsequent behavior and in measuring what shapes this interpretation.     

Integrating strategic issues into strategic management

The notion of a ‘strategic issues’ is rather pervasive in the field of planning in both conceptual [5, 19] and practical contexts. For instance, sometime ago the Wall Street Journal [41] reported that at least 50 large firms have created positions of ‘issues management director’; a dramatic increase in the number of such positions. ‘True’ strategic issues have a readily apparent importance to any organization; yet the process of identifying such issues and of integrating them into strategic planning and management is not well developed. Most treatments of strategic issues deal only with specific segments of the overall process through which relevant issues may be initially identified and finally translated into appropriate strategy [e.g. 5, 17]. This paper demonstrates that it is practical to develop a comprehensive process of ‘strategic issue management’ (SIM) that will facilitate the systematic identification, assessment and analysis of such issues. Such a process can ensure that issue-related factors are fully integrated into the formulation and implementation of strategy and plans. As such, SIM is a process whereby strategic issues may become an integral element of strategic management.     

Determinants of fertility levels and change among developed countries: 1958–1978

This article provides a multivariate cross-national test of the hypothesis that national population/family planning policies have effected levels, and changes in fertility in developed nations over the past two decades. Variation is assessed in the total fertility rates (TFR) in 1978, and in the change in these rates between 1958 and 1978, among thirty developed countries. Measures include socioeconomic development, divorce, percent in consensual unions, female labor force participation, abortion policy, and level of contraceptive use by married couples and, government population/family planning policy. Seventy percent of the variation in 1978 TFR is related to the percent contracepting, female labor force, and the population/family planning policy measures. These are the only measures with significant direct effects. A longitudinal analysis of 1958 to 1978 change in TFRs is also conducted. This model increases R² to 75%, and the three independent variables remain significant. Implications of these findings for policy makers interested in increasing or decreasing fertility rates are noted.