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871.
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.  相似文献   
872.
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.  相似文献   
873.
874.
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.  相似文献   
875.
‘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.  相似文献   
876.
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.  相似文献   
877.
In this article, for the first time, we propose the negative binomial–beta Weibull (BW) regression model for studying the recurrence of prostate cancer and to predict the cure fraction for patients with clinically localized prostate cancer treated by open radical prostatectomy. The cure model considers that a fraction of the survivors are cured of the disease. The survival function for the population of patients can be modeled by a cure parametric model using the BW distribution. We derive an explicit expansion for the moments of the recurrence time distribution for the uncured individuals. The proposed distribution can be used to model survival data when the hazard rate function is increasing, decreasing, unimodal and bathtub shaped. Another advantage is that the proposed model includes as special sub-models some of the well-known cure rate models discussed in the literature. We derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes. We analyze a real data set for localized prostate cancer patients after open radical prostatectomy.  相似文献   
878.
879.
Revisiting the work of Weber [Weber, M. (1921). The theory of social and economic organizations. New York: Free Press], Mumford and colleagues (e.g., [Strange, J. M., & Mumford, M. D. (2002). The origins of vision: Charismatic versus ideological leadership. Leadership Quarterly, 13, 343?377; Mumford, M.D. (2006). Pathways to outstanding leadership: A comparative analysis of charismatic, ideological and pragmatic leaders. Mahwah, NJ: Erlbaum.]) explored the thesis that in addition to charismatic leadership, there exist at least two additional pathways to outstanding leadership: ideological and pragmatic. Despite the compelling results of initial studies, however, questions remain as to when and under what situational conditions these three leaders operate most effectively. As such, an experiment was conducted to investigate two noteworthy contextual influences: 1) situational congruence with a leader's mental model and 2) environmental complexity. The experiment made use of a computerized leadership simulation where participants took on the role of a university chancellor. Results indicate that leader type, complexity, and situational framing were critical factors in determining leader performance on multiple game performance criteria as well as creative process criteria. Implications and avenues for future research are discussed.  相似文献   
880.
Let G be a graph and be the complement of G. The complementary prism of G is the graph formed from the disjoint union of G and by adding the edges of a perfect matching between the corresponding vertices of G and . For example, if G is a 5-cycle, then is the Petersen graph. In this paper we consider domination and total domination numbers of complementary prisms. For any graph G, and , where γ(G) and γ t (G) denote the domination and total domination numbers of G, respectively. Among other results, we characterize the graphs G attaining these lower bounds. Research supported in part by the South African National Research Foundation and the University of KwaZulu-Natal.  相似文献   
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