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51.
abstractDespite the attention given to universal design in recent years, many people with impairments still refrain from travelling on public transport. This explorative case study, conducted in the greater Oslo region in Norway, aims to add knowledge on why this is so. Findings indicate that insecurity while travelling and expectations of problems along the way are significant barriers. For many it is the sum of all challenges combined, from experience or anticipation that leads to non-use of public transport. The study shows that universal design policy, as of today, does not lead to accessible public transport systems that rendered impairments irrelevant. If society could safeguard the individuals’ travel needs, this might have profound societal repercussions through increased workforce participation and value added in society. Only then can society make the best use of all its inhabitants while championing inclusiveness and equality. 相似文献
52.
Two-stage designs offer substantial advantages for early phase II studies. The interim analysis following the first stage allows the study to be stopped for futility, or more positively, it might lead to early progression to the trials needed for late phase II and phase III. If the study is to continue to its second stage, then there is an opportunity for a revision of the total sample size. Two-stage designs have been implemented widely in oncology studies in which there is a single treatment arm and patient responses are binary. In this paper the case of two-arm comparative studies in which responses are quantitative is considered. This setting is common in therapeutic areas other than oncology. It will be assumed that observations are normally distributed, but that there is some doubt concerning their standard deviation, motivating the need for sample size review. The work reported has been motivated by a study in diabetic neuropathic pain, and the development of the design for that trial is described in detail. 相似文献
53.
Most studies of quality improvement deal with ordered categorical data from industrial experiments. Accounting for the ordering of such data plays an important role in effectively determining the optimal factor level of combination. This paper utilizes the correspondence analysis to develop a procedure to improve the ordered categorical response in a multifactor state system based on Taguchi's statistic. Users may find the proposed procedure in this paper to be attractive because we suggest a simple and also popular statistical tool for graphically identifying the really important factors and determining the levels to improve process quality. A case study for optimizing the polysilicon deposition process in a very large-scale integrated circuit is provided to demonstrate the effectiveness of the proposed procedure. 相似文献
54.
An approach to the analysis of time-dependent ordinal quality score data from robust design experiments is developed and applied to an experiment from commercial horticultural research, using concepts of product robustness and longevity that are familiar to analysts in engineering research. A two-stage analysis is used to develop models describing the effects of a number of experimental treatments on the rate of post-sales product quality decline. The first stage uses a polynomial function on a transformed scale to approximate the quality decline for an individual experimental unit using derived coefficients and the second stage uses a joint mean and dispersion model to investigate the effects of the experimental treatments on these derived coefficients. The approach, developed specifically for an application in horticulture, is exemplified with data from a trial testing ornamental plants that are subjected to a range of treatments during production and home-life. The results of the analysis show how a number of control and noise factors affect the rate of post-production quality decline. Although the model is used to analyse quality data from a trial on ornamental plants, the approach developed is expected to be more generally applicable to a wide range of other complex production systems. 相似文献
55.
The responses obtained from response surface designs that are run sequentially often exhibit serial correlation or time trends. The order in which the runs of the design are performed then has an impact on the precision of the parameter estimators. This article proposes the use of a variable-neighbourhood search algorithm to compute run orders that guarantee a precise estimation of the effects of the experimental factors. The importance of using good run orders is demonstrated by seeking D-optimal run orders for a central composite design in the presence of an AR(1) autocorrelation pattern. 相似文献
56.
Doubly adaptive biased coin design (DBCD) is an important family of response-adaptive randomization procedures for clinical trials. It uses sequentially updated estimation to skew the allocation probability to favor the treatment that has performed better thus far. An important assumption for the DBCD is the homogeneity assumption for the patient responses. However, this assumption may be violated in many sequential experiments. Here we prove the robustness of the DBCD against certain time trends in patient responses. Strong consistency and asymptotic normality of the design are obtained under some widely satisfied conditions. Also, we propose a general weighted likelihood method to reduce the bias caused by the heterogeneity in the inference after a trial. Some numerical studies are also presented to illustrate the finite sample properties of DBCD. 相似文献
57.
Mediation and moderation are two theories for refining and understanding a causal relationship. Empirical investigation of
mediators and moderators requires an integrated research design rather than the data analyses driven approach often seen in
the literature. This paper described the conceptual foundation, research design, data analysis, as well as inferences involved
in a mediation and/or moderation investigation in both experimental and non-experimental (i.e., correlational) contexts. The
essential distinctions between the investigation of mediators and moderators were summarized and juxtaposed in an example
of a causal relationship between test difficulty and test anxiety. In addition, the more elaborate models, moderated mediation
and mediated moderation, the use of structural equation models, and the problems with model misspecification were discussed
conceptually.
相似文献
Bruno D. ZumboEmail: |
58.
农民工社会养老保险局部推进制度设计研究 总被引:1,自引:0,他引:1
GONG Xiu-quan 《人口与经济》2008,(6)
建立农民工社会保障将促进我国经济和社会协调互动发展。在分析影响农民工社会养老保险各因素的基础上,设计了符合当前我国农民工社会养老保险局部推进战略的制度模式。该模式建立了自动对农民工分层分类的机制,充分考虑了我国城镇职工基本养老保险的未来改革,在保证政府承担有限责任的基础上保护了农民工的权益并平衡了企业利益。 相似文献
59.
Anette Bengs Annika Wiklund-Engblom Joachim Majors Anas Ashfaq 《Innovation: The European Journal of Social Science Research》2018,31(2):106-124
We present our design of a digital service supporting social inclusion among immigrant women in an ethnically and socially diverse neighbourhood of a small Finnish town. The aim is to explore experiences and perceptions as well as potential barriers and challenges for using the web-based service. The case study is framed as design research having a strong user-centred design approach. We describe the design process and present the results of a mixed-method evaluation. The results are scrutinized from the perspectives of experience design. The analysis reveals a potential to facilitate social inclusion through the fulfilment of needs related to relatedness, autonomy, competence, pleasure and stimulations as well as popularity. However, some challenges in the interface design and communication of the security and purpose of the site were identified in the study. Significant differences were also found between immigrant women and local people regarding the need for this digital service. 相似文献
60.
The time‐dependent “cure‐death” model investigating two equally important endpoints simultaneously in trials treating high‐risk patients with resistant pathogens 下载免费PDF全文
A variety of primary endpoints are used in clinical trials treating patients with severe infectious diseases, and existing guidelines do not provide a consistent recommendation. We propose to study simultaneously two primary endpoints, cure and death, in a comprehensive multistate cure‐death model as starting point for a treatment comparison. This technique enables us to study the temporal dynamic of the patient‐relevant probability to be cured and alive. We describe and compare traditional and innovative methods suitable for a treatment comparison based on this model. Traditional analyses using risk differences focus on one prespecified timepoint only. A restricted logrank‐based test of treatment effect is sensitive to ordered categories of responses and integrates information on duration of response. The pseudo‐value regression provides a direct regression model for examination of treatment effect via difference in transition probabilities. Applied to a topical real data example and simulation scenarios, we demonstrate advantages and limitations and provide an insight into how these methods can handle different kinds of treatment imbalances. The cure‐death model provides a suitable framework to gain a better understanding of how a new treatment influences the time‐dynamic cure and death process. This might help the future planning of randomised clinical trials, sample size calculations, and data analyses. 相似文献