Operations in the Service Industries: Introduction to the Special Issue

This special issue of Production and Operations Management offers a sample of ongoing research that focuses currently on the services industries. The articles selected cover a spectrum of application areas as well as methodologies.     

Improved adaptive group testing algorithms with applications to multiple access channels and dead sensor diagnosis

We study group-testing algorithms for resolving broadcast conflicts on a multiple access channel (MAC) and for identifying the dead sensors in a mobile ad hoc wireless network. In group-testing algorithms, we are asked to identify all the defective items in a set of items when we can test arbitrary subsets of items. In the standard group-testing problem, the result of a test is binary—the tested subset either contains defective items or not. In the more generalized versions we study in this paper, the result of each test is non-binary. For example, it may indicate whether the number of defective items contained in the tested subset is zero, one, or at least two. We give adaptive algorithms that are provably more efficient than previous group testing algorithms. We also show how our algorithms can be applied to solve conflict resolution on a MAC and dead sensor diagnosis. Dead sensor diagnosis poses an interesting challenge compared to MAC resolution, because dead sensors are not locally detectable, nor are they themselves active participants. A preliminary version of this paper was presented at SPAA 2006.     

Care: A Critical Review of Theory,Policy and Practice

‘Care’ is a source of critical tension in current social theory, and the policy and practice implications of that tension are evidenced in its current prominence on the political agenda of developed welfare states. This article critically appraises current developments in the theory, policy and practice of care, drawing on interdisciplinary developments in political theory, sociology and social policy. Developing feminist and disability‐rights theories, it explores a critical synthesis of conflicting normative and theoretical positions regarding the giving and receiving of care, and of the ethics and justice of care. It examines case studies of current comparative policy developments across a range of different welfare regimes, including the marketization/commodification and de/re‐familiaization of care, exploring ideological and normative trends in the design of contemporary policies. It discusses the impact of theory and policy on the practice of care, looking particularly at the issue of long‐term care for disabled and older adults. Finally, the authors argue for the development of a citizenship‐based approach to care that decouples it from individualistic and paternalistic paradigms that disempower those who give and receive care.     

A new double sampling control chart for monitoring process mean using auxiliary information

Statistical quality control charts have been widely accepted as a potentially powerful process monitoring tool because of their excellent speed in tracking shifts in the underlying process parameter(s). In recent studies, auxiliary-information-based (AIB) control charts have shown superior run length performances than those constructed without using it. In this paper, a new double sampling (DS) control chart is constructed whose plotting-statistics requires information on the study variable and on any correlated auxiliary variable for efficiently monitoring the process mean, namely AIB DS chart. The AIB DS chart also encompasses the classical DS chart. We discuss in detail the construction, optimal design, run length profiles, and the performance evaluations of the proposed chart. It turns out that the AIB DS chart performs uniformly better than the DS chart when detecting different kinds of shifts in the process mean. It is also more sensitive than the classical synthetic and AIB synthetic charts when detecting a particular shift in the process mean. Moreover, with some realistic beliefs, the proposed chart outperforms the exponentially weighted moving average chart. An illustrative example is also presented to explain the working and implementation of the proposed chart.     

Double sampling |S| control chart with variable sample size and variable sampling interval

This study presents a control chart for monitoring shifts in the covariance matrix of a multivariate normally distributed process. This chart combines the double sampling, variable sample size and variable sampling interval features, and is called the DSVSSI |S| chart. A Markov chain approach is developed to design the DSVSSI |S| chart, by minimizing the average time to signal (ATS), for a specified shift size in the covariance matrix. The DSVSSI |S| chart has a better ATS performance compared to other existing charts. An example is given to illustrate the operation of the DSVSSI |S| chart.     

Shards of the old looking glass: restoring the significance of identity in promoting positive outcomes for looked‐after children

There is a driving force within current UK child welfare policies which promotes a strengths led approach to both assessment and care planning for children in need. Social policy emphasizes the importance of tangible outcomes such as education achievement, which have been enshrined in statute. However, other developmental outcomes, such as identity, are subordinated. Notwithstanding the relevance of these more concrete indicators, this paper suggests that this focus has left a gap at theoretical, strategic and operational levels relating to more psychosocial aspects of human growth and development, such as identity. This paper seeks to redress that gap by considering identity as both a process and an outcome. Following a review of the literature on identity development, it presents an analysis of semi‐structured interviews with 13 young people and their social workers. The findings show how young people's identity is shaped by their relationships, can be a protective mechanism, and deferred or put on standby. In the concluding discussion the implications for social work practice are highlighted.     

The Civilizing Process of Trust: Developing Quality Mechanisms which are Local,Professional‐led and thus Legitimate

‘Quality’ and ‘performance’ have become defining concepts for policymakers and health‐care systems alike. Yet whilst these principles are of fundamental importance, their practical implementation and assurance are far from straightforward. This commentary analyses the difficulties faced in enhancing quality and performance in the English NHS. Many recent initiatives have been driven through incentives and external auditing of the professionals providing health care on the frontline. Drawing on recent literature and research findings, we argue that this checking‐based ‘audit culture’ is fundamentally flawed in driving quality and performance. Many targets and measures are too crude to reflect important aspects affecting patient outcomes and therefore these frameworks lack legitimacy amongst professionals. An alternative, trust‐based model is proposed – one more capable of acknowledging the meaning, complexity and specificities inherent to professional work. Quality mechanisms developed locally by professionals are able to produce the legitimacy crucial for their effectiveness. It is argued that the normative obligation of approaches based on conditional trust is a more compelling incentive towards good practice than targets and sanctions. This governance by ‘the social’ is able to motivate a more holistically enlightened and consistent reflexivity towards practice, though it is only able to flourish in the absence of purposive‐rational systems.     

Three's a crowd? The Nader vote in the 2000 presidential, election in U.S. metropolitan areas

The 2000 U.S. presidential election resulted in one of the closest and most controversial outcomes in U.S. history. Green Party candidate Ralph Nader had little chance of winning, but nevertheless impacted the race in several close states and arguably swung the race from Al Gore to George W. Bush. This research examines Ralph Nader's “urban strategy” to win 5% of the vote for president and the bases of his electoral support. This study uses the METRO_2000 data set which contains a variety of publicly available variables for 276 U.S. metropolitan statistical areas (MSAs) in the year 2000. The analysis uses OLS regression to examine the determinants of the percentage of the vote for Nader in each MSA. The results indicate that the Nader vote was positively influenced by key electoral variables such as the level of electoral participation, whether Nader was on the ballot or could be written in, and the closeness of the race in state polls leading up to the election. The Nader vote was also higher in MSAs with high percentages of voters who supported Nader programs including environmentalists, those favoring universal health care and gay rights, union members, and MSAs that were college towns or with high percentages of college-educated voters. Ralph Nader's urban strategy effectively mobilized enough of his electoral base to impact the 2000 election, but electoral constraints and the closeness of the race prevented him from achieving his goal of attaining 5% of the vote. This case holds lessons about the limits and possibilities of third party campaigns in U.S. presidential elections.