Adaptive Bayesian compound designs for dose finding studies

We consider the problem of how to efficiently and safely design dose finding studies. Both current and novel utility functions are explored using Bayesian adaptive design methodology for the estimation of a maximum tolerated dose (MTD). In particular, we explore widely adopted approaches such as the continual reassessment method and minimizing the variance of the estimate of an MTD. New utility functions are constructed in the Bayesian framework and are evaluated against current approaches. To reduce computing time, importance sampling is implemented to re-weight posterior samples thus avoiding the need to draw samples using Markov chain Monte Carlo techniques. Further, as such studies are generally first-in-man, the safety of patients is paramount. We therefore explore methods for the incorporation of safety considerations into utility functions to ensure that only safe and well-predicted doses are administered. The amalgamation of Bayesian methodology, adaptive design and compound utility functions is termed adaptive Bayesian compound design (ABCD). The performance of this amalgamation of methodology is investigated via the simulation of dose finding studies. The paper concludes with a discussion of results and extensions that could be included into our approach.     

The development of the resource-based view of the firm: A critical appraisal

Over the last 20 years, the resource-based view (RBV) has reached a pre-eminent position among theories in the field of strategy, but debate continues as to its precise nature. This paper contributes to the debate by critically reviewing the development of the RBV to date. The critical appraisal examines the development of the RBV in terms of theory, method, empirical evidence and practical insights. It is contended that the permeable and eclectic nature of the RBV stems from its being a theory about what firms are and how they function, and that its popularity is due to an absence of limiting behavioural assumptions. Finally, the authors provide their own subjective views on where they think RBV scholars should focus their efforts in the future.     

‘Shared intelligibility’ and two reflexive strategies as methods of supporting ‘responsible decisions’ in a hermeneutic phenomenological study

Hermeneutic phenomenologists propose that researchers inescapably bring themselves into their research because interpretation must inevitably be influenced by their contexts and pre-understandings. They propose that interpretation is a dynamic and active part of the construction of a text’s meaning, and involvement in this construction process leads to deep empathic understanding of others’ experience, reappraisal of accepted social and cultural systems, and a level of self-enlightenment. The strengths of the hermeneutic methodological approach have led to its use in a number of disciplines, however, there remains concerns about interpretative validity. It is widely acknowledged that in order to support rigour and validity in hermeneutic studies, researchers are required to develop and integrate strategies within the research process to promote awareness of the interplay between their pre-understandings and interpretation. This paper discusses how episodic interviewing which capitalizes on ‘shared intelligibility’, and the reflexive strategies of ‘oppositional arrangement of perspectives’ and ‘backgrounding’ were used to shed light on data from a study of the experiences and views of nursing home nurses regarding their occupational role and status, and work identity.     

Teaching Tacting of Private Events Based on Public Accompaniments: Effects of Contingencies,Audience Control,and Stimulus Complexity

Our current understanding of the role of private events in the science of behavior is based largely on Skinner’s natural science interpretation of private events. Skinner described public accompaniments as one source of control for a verbal community to differentially reinforce verbal behavior regarding private events. In this study, we developed an experimental analogue to study variables influencing tacting of private events. The participant had exclusive access to one set of stimuli (the private stimuli), and the experimenter attempted to teach tacts for private stimuli based on their correspondence with public stimuli accessible to both the experimenter and participant. Results of experiments 1 and 2 demonstrated that reports of private stimuli were a function of degree of public-private correspondence, reinforcement contingency, and audience control. In some cases, we encountered reports controlled exclusively by public stimuli. Results of experiment 3 showed that public control was less likely when public stimuli were more complex and the experimenter had a unique behavioral history with respect to those stimuli that was not shared by the learner. The orderly patterns of data obtained suggest that analogue arrangements might be a useful, and even necessary, starting point for experimental investigations of how private events may enter into the analysis of behavior.     

Why targeting matters: The apprenticeship program for youth in the Czech Republic

In this paper, we analyze the targeting and outcomes of the apprenticeship program implemented under the Youth Guarantee/YG scheme in the Czech Republic. We examine the outcomes and targeting using counterfactual impact evaluation (quasi-experimental design) of the apprenticeship program on the basis of administrative data from the Czech Employment Office. The implementation strategy is analyzed using various policy documents. The findings indicate that the program is apparently targeted at those groups of young people who are less disadvantaged as regards education level and previous unemployment experience. At the same time, paradoxically, the effects in terms of outflows from the unemployment register are weak for the short-term and medium-term unemployed, as well as for low-skilled and high-skilled youth, and stronger effects are evident in the case of long-term unemployed and medium-skilled youth. The failures in targeting and in adjusting the program to the needs of more vulnerable groups of youth are due to an inconsistent implementation strategy of Czech Public Employment Services.     

Wildfire Risk Transmission in the Colorado Front Range,USA

Wildfires are a global phenomenon that in some circumstances can result in human casualties, economic loss, and ecosystem service degradation. In this article we spatially identify wildfire risk transmission pathways and locate the areas of highest exposure of human populations to wildland fires under severe, but not uncommon, weather events. We quantify varying levels of exposure in terms of population potentially affected and tie the exposure back to the spatial source of the risk for the Front Range of Colorado, USA. We use probabilistic fire simulation modeling to address where fire ignitions are most likely to cause the highest impact to human communities, and to explore the role that various landowners play in that transmission of risk. Our results indicated that, given an ignition and the right fire weather conditions, large areas along the Front Range in Colorado could be exposed to wildfires with high potential to impact human populations, and that overall private ignitions have the potential to impact more people than federal ignitions. These results can be used to identify high‐priority areas for wildfire risk mitigation using various mitigation tools.