195 resultados para Missing values


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Transparent evidence-based decision making has been promoted worldwide to engender trust in science and policy making. Yet, little attention has been given to transparency implementation. The degree of transparency (focused on how uncertain evidence was handled) during the development of folate and vitamin D Dietary Reference Values was explored in three a priori defined areas: (i) value request; (ii) evidence evaluation; and (iii) final values.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Missing data is a common phenomenon with survey-based research; patterns of missing data may elucidate why participants decline to answer certain questions. Objective: To describe patterns of missing data in the Pediatric Quality of Life and Evaluation of Symptoms Technology (PediQUEST) study, and highlight challenges in asking sensitive research questions. Design: Cross-sectional, survey-based study embedded within a randomized controlled trial. Setting: Three large children's hospitals: Dana-Farber/Boston Children's Cancer and Blood Disorders Center (DF/BCCDC); Children's Hospital of Philadelphia (CHOP); and Seattle Children's Hospital (SCH). Measurements: At the time of their child's enrollment, parents completed the Survey about Caring for Children with Cancer (SCCC), including demographics, perceptions of prognosis, treatment goals, quality of life, and psychological distress. Results: Eighty-six of 104 parents completed surveys (83% response). The proportion of missing data varied by question type. While 14 parents (16%) left demographic fields blank, over half (n=48; 56%) declined to answer at least one question about their child's prognosis, especially life expectancy. The presence of missing data was unrelated to the child's diagnosis, time from progression, time to death, or parent distress (p>0.3 for each). Written explanations in survey margins suggested that addressing a child's life expectancy is particularly challenging for parents. Conclusions and Relevance: Parents of children with cancer commonly refrain from answering questions about their child's prognosis, however, they may be more likely to address general cure likelihood than explicit life expectancy. Understanding acceptability of sensitive questions in survey-based research will foster higher quality palliative care research. © Copyright 2014, Mary Ann Liebert, Inc. 2014.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper raises issues concerning the relationship between student assessment and the values which academic institutions propagate. It argues that many current assessment practices are incompatible with the goals of independence, thoughtfulness and critical analysis to which most academics would subscribe; that forms of assessment which are commonplace are not consistent with the behaviour of academics in their own contributions to knowledge; and that there is evidence to suggest that the assessment policy of many departments undermines deep approaches to learning on the part of students. Some indications are given of possible strategies to address the problems which have been identified, drawing upon ideas from academic and professional practice in general and self-assessment and peer review in particular.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper, a novel robust finite-horizon Kalman filter is developed for discrete linear time-varying systems with missing measurements and normbounded parameter uncertainties. The missing measurements are modelled by a Bernoulli distributed sequence and the system parameter uncertainties are in the state and output matrices. A two stage recursive structure is considered for the Kalman filter and its parameters are determined guaranteeing that the covariances of the state estimation errorsare not more than the known upper bound. Finally, simulation results are presented to illustrate the outperformance of the proposed robust estimator compared with the previous results in the literature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The consideration of information on social values in conjunction with biological data is critical for achieving both socially acceptable and scientifically defensible conservation planning outcomes. However, the influence of social values on spatial conservation priorities has received limited attention and is poorly understood. We present an approach that incorporates quantitative data on social values for conservation and social preferences for development into spatial conservation planning. We undertook a public participation GIS survey to spatially represent social values and development preferences and used species distribution models for 7 threatened fauna species to represent biological values. These spatially explicit data were simultaneously included in the conservation planning software Zonation to examine how conservation priorities changed with the inclusion of social data. Integrating spatially explicit information about social values and development preferences with biological data produced prioritizations that differed spatially from the solution based on only biological data. However, the integrated solutions protected a similar proportion of the species' distributions, indicating that Zonation effectively combined the biological and social data to produce socially feasible conservation solutions of approximately equivalent biological value. We were able to identify areas of the landscape where synergies and conflicts between different value sets are likely to occur. Identification of these synergies and conflicts will allow decision makers to target communication strategies to specific areas and ensure effective community engagement and positive conservation outcomes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

K’gari-Fraser Island, the world's largest barrier sand island, is at the crossroads of World Heritage status, due to destructive environmental use in concert with climate change. Will K’gari-Fraser Island exemplify innovative, adaptive management or become just another degraded recreational facility? We synthesize the likely impact of human pressures and predicted consequences on the values of this island. World-renown natural beauty and ongoing biological and geological processes in coastal, wetland, heathland and rainforest environments, all contribute to its World Heritage status. The impact of hundreds of thousands of annual visitors is increasing on the island's biodiversity, cultural connections, ecological functions and environmental values. Maintaining World Heritage values will necessitate the re-framing of values to integrate socioeconomic factors in management and reduce extractive forms of tourism. Environmentally sound, systematic conservation planning that achieves social equity is urgently needed to rectify historical mistakes and update current management practices. Characterizing and sustaining biological refugia will be important to retain biodiversity in areas that are less visited. The development of a coherent approach to interpretation concerning history, access and values is required to encourage a more sympathetic use of this World Heritage environment. Alternatively, ongoing attrition of the islands values by increased levels of destructive use is inevitable.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

PURPOSE: Preventable patient harm due to adverse events (AEs) is a significant health problem today facing contemporary health care. Knowledge of patients' experiences of AEs is critical to improving health care safety and quality. A systematic review of studies of patients' experiences of AEs was conducted to report their experiences, knowledge gaps and any challenges encountered when capturing patient experience data. DATA SOURCES: Key words, synonyms and subject headings were used to search eight electronic databases from January 2000 to February 2015, in addition to hand-searching of reference lists and relevant journals. STUDY SELECTION: Titles and abstracts of publications were screened by two reviewers and checked by a third. Full-text articles were screened against the eligibility criteria. DATA EXTRACTION: Data on design, methods and key findings were extracted and collated. RESULTS: Thirty-three publications demonstrated patients identifying a range of problems in their care; most commonly identified were medication errors, communication and coordination of care problems. Patients' income, education, health burden and marital status influence likelihood of reporting. Patients report distress after an AE, often exacerbated by receiving inadequate information about the cause. Investigating patients' experiences is hampered by the lack of large representative patient samples, data over sufficient time periods and varying definitions of an AE. CONCLUSION: Despite the emergence of policy initiatives to enhance patient engagement, few studies report patients' experiences of AEs. This information must be routinely captured and utilized to develop effective, patient-centred and system-wide policies to minimize and manage AEs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In today's dynamic business environment the success of a firm often depends on its ability to create brand loyalty. While there is a large body of research exploring brand loyalty and its antecedents, little has been done to examine how the relationship between these antecedents and brand loyalty is moderated by consumer differences in individual level collectivist values. This understanding is important however as consumers high in individual level collectivist values have been found to make different brand choices than consumers low in individual level collectivist values. We develop and test theory that suggests consumer differences in individual level collectivist values have a significant moderating effect on the relationship between perceived value, perceived quality, brand trust and brand loyalty. The results show that consumers high in individual level collectivist values are significantly more loyal to a focal brand, especially when brand trust and perceived quality are at relatively low levels. © 2014 Elsevier Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study examines whether individually held cultural values moderate the relationship between transformational leadership behavior of supervisors and the job involvement of subordinates in the Middle Eastern organizational context. Hierarchical regression analysis was used to analyze survey data from 229 employees of 10 organizations in the United Arab Emirates. In line with the findings of studies in Western countries, transformational leadership was found to influence job involvement positively. In addition, the cultural value orientations of individuals were found to moderate this relationship. Collectivism positively influenced the relationship between transformational leadership and job involvement, whereas uncertainty avoidance had a negative effect. These findings provide an insight into how transformational leadership may be used to motivate culturally diverse groups of employees within the Middle East. To enhance job involvement, organizations need to realize that the attitudinal response of subordinates to transformational leadership can depend on their cultural values. This has significant implications regarding the training and effective deployment of transformational leaders within Middle Eastern organizations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research aims to understand why one of two almost identical subspecies of the Australian yellow chat Ephthianura crocea has received significantly higher levels of local and institutional support than the other despite both having the same conservation status and taxonomic distinctiveness, factors commonly thought to influence conservation effort. Using a qualitative multiple case study approach we explored how a range of social factors, including stakeholder attitudes and institutional, policy and operational aspects, might have affected conservation efforts for the two taxa. Our results suggest that the conservation trajectories of these two subspecies have diverged since their identification as threatened species in 2000 because of differences in the social landscapes within which they persist. For one subspecies local advocacy was kindled initially by the small number of local endemic bird species but developed into a strong emotional engagement, resulting in increased local awareness, government funding, and effectiveness of conservation action. The other subspecies has had to compete for attention with approximately 200 other threatened taxa occurring in its region. No individual advocate has accorded this subspecies a high priority for action, and none of those responsible for its conservation have seen it or acknowledged an emotional attachment to it. Our findings confirm that initiation of conservation effort is strongly tied to the social values of individuals with power to take action, regardless of legislation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We investigated how the socio–political and ecological environment are associated with the conservation management strategies for two rare, endemic and almost identical Australian white-tailed black-cockatoos: Baudin's (Calyptorhynchus baudinii) and Carnaby's black-cockatoo (C. latirostris). Substantially less investment and action has occurred for Baudin's black-cockatoo. Interviews with key informants revealed that this disparity has probably arisen because Baudin's black-cockatoo has long been considered a pest to the apple industry, lives primarily in tall forests and has had little research undertaken on its biology and threats. By contrast, Carnaby's black-cockatoo has been the subject of one of the longest running research projects in Australia, is highly visible within the urban environment and does not appear to affect the livelihoods of any strong stakeholder group. We suggest the social context within which recovery efforts occur could be an important determinant in species persistence. We argue that social research is fundamental to a better understanding of the nature of efforts to conserve particular species, the factors associated with these efforts and their likelihood of success.