A quasi-Newton acceleration for high-dimensional optimization algorithms

In many statistical problems, maximum likelihood estimation by an EM or MM algorithm suffers from excruciatingly slow convergence. This tendency limits the application of these algorithms to modern high-dimensional problems in data mining, genomics, and imaging. Unfortunately, most existing acceleration techniques are ill-suited to complicated models involving large numbers of parameters. The squared iterative methods (SQUAREM) recently proposed by Varadhan and Roland constitute one notable exception. This paper presents a new quasi-Newton acceleration scheme that requires only modest increments in computation per iteration and overall storage and rivals or surpasses the performance of SQUAREM on several representative test problems.     

Implementing a Multidimensional Poverty Measure Using Mixed Methods and a Participatory Framework

Recently, there have been advances in the development of multidimensional poverty measures. Work is needed however on how to implement such measures. This paper deals with the process of selecting dimensions and setting weights in multidimensional poverty measurement using qualitative and quantitative methods in a participatory framework. We estimate the multidimensional poverty measures developed by Alkire and Foster for a particular group: persons with psychiatric diagnoses in the United States. To select relevant dimensions and their relative ordering, two discussion groups are convened: one consisting of persons with lived-experience expertise and the other consisting of people with mental health service provision or research expertise. Several methods are used to convert dimension rankings into weights. The selection and ordering of dimensions differed between the two discussion groups, as did the resulting poverty measures. For instance, the poverty headcount using the dimensions and weights of the ‘lived experience’ group ranged from 20.61 to 26.96% as compared to a range of 18.62–33.19% using those of the ‘provider/researcher’ group. One of the main results of this study is that the Alkire Foster method is sensitive to the selection of dimensions and the methods used to derive rankings and weights. It points toward the limitation of relying exclusively on small scale qualitative methods for the selection and ranking of dimensions. In addition, the participatory framework used in this study was found to be essential in interpreting results, in particular with respect to the limitations of the data set in measuring relevant dimensions.     

The role of inferential accuracy in performance rating

The presence of shared implicit theories of performance is used in explaining the failure of behavioral anchors to improve performance ratings. It is proposed that efforts to improve rating accuracy also will be hampered by a preoccupation with observation. Instead, attention needs to be focused on the inferential accuracy of the rater and the cognitive processes and implicit theories upon which raters rely.     

Ethical Considerations in Management Research: A ‘Truth’ Seeker's Guide

Within a growing Knowledge-Management context, it would appear that Management Research calls for researchers to explicitly understand their own values, have increasing capacity for reflexivity and anticipate various ethical dilemmas that emerge from the research endeavour. This paper provides an overview of the philosophy of ethics and focuses on a researcher's ethical reasoning. It provides a framework for understanding causes of ethical dilemmas in the context of management research and provides strategies for a way forward through such dilemmas. The paper, finally, outlines exercises pertinent to research ethics and ‘hands on’ research praxis.     

Ethical Considerations in Management Research: A ‘Truth’ Seeker''s Guide

Within a growing Knowledge-Management context, it would appear that Management Research calls for researchers to explicitly understand their own values, have increasing capacity for reflexivity and anticipate various ethical dilemmas that emerge from the research endeavour. This paper provides an overview of the philosophy of ethics and focuses on a researcher's ethical reasoning. It provides a framework for understanding causes of ethical dilemmas in the context of management research and provides strategies for a way forward through such dilemmas. The paper, finally, outlines exercises pertinent to research ethics and ‘hands on’ research praxis. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Dilemma of Privatized Public Services: Philosophical Frames in Understanding Failure and Managing Partnership Terminations

This paper uses social theory to explicate the competing perspectives on the on-going and, increasing, privatization of public services in the U.K. It suggests that if business ignores these perspectives then political imperatives will come into play that will inevitably turn privatization initiatives commercially sour.Contrary to political rhetoric, public/private partnerships (PPPs) constitute a more strategic form and process of out-sourcing, demanding that wherever public funding flows, private rent-seeking opportunities be created for the private sector. Seen in these terms, managerial elites will need to understand and anticipate conditions under which the state would seek to terminate lucrative partnering arrangements in the public interest.Political–administrative dialogue on partnerships can involve an unresponsive discourse or a dialogue of the deaf, both constituting a threat to business through the imposition of undefined community service obligations or hostile and unprofitable terminations by the state. Performance required of PPPs goes beyond market success and requires co-optation of strategic stakeholders, raising significant issues about corporate governance directions. Business leaders will need to develop communicative rationalities that build pluralized decision structures and implementation capacities. The paper concludes by outlining design features of more effective regulatory regimes to avoid hostile and unprofitable terminations of increasingly contested PPPs. The conclusion is less sanguine about the ability, or even the wish, of governments to do so.     

Sex offender notification and protective behavior

A primary purpose of sex offender community notification statutes is to give community members the opportunity to engage in precautionary behavior to prevent victimization. This exploratory study examines the effect of notification by comparing the behavior of 87 Hamilton County, Ohio, residents receiving sex offender notification to the behavior of 149 other residents who had not received notification. The findings indicate that notified respondents are significantly more likely to engage in behaviors to protect themselves and others from victimization, and to engage in community reporting behavior.     

The potential of the SSI program to reduce poverty among the elderly

Is it more effective to reduce poverty among the elderly by increasing the benefits paid by the Supplemental Security Income (SSI) program or by increasing eligibility for the program? This paper answers that question from a policymaker's perspective. At given program cost levels, we compare the potential reduction in poverty from increasing benefit levels to the potential reduction associated with a variety of policy proposals that would increase eligibility for the program. This paper employs a microsimulation model containing an eligibility and benefits calculator, a participation model, and an optimization algorithm. The data are from the Survey of Income and Program Participation supplemented by the administrative records of the SSI program. The results show that increasing eligibility by relaxing the restrictions of the means tests can be more effective in reducing poverty than raising benefit levels.     

Men and women who like continuous shiftwork are more ‘hardy’: But what does it mean?

Abstract

Continuous shiftworkers of both genders who like shiftwork and report fewer digestive problems have higher scores on hardiness than those who dislike shiftwork. Whether this is a causal, consequential or accidental relationship requires a longitudinal investigation. It is also not clear how far ‘hardiness’ is a personality measure, a behavioural style, a coping strategy, or a consequence of the stress of shiftwork.