2,364 research outputs found
Generalized fiducial inference for normal linear mixed models
While linear mixed modeling methods are foundational concepts introduced in
any statistical education, adequate general methods for interval estimation
involving models with more than a few variance components are lacking,
especially in the unbalanced setting. Generalized fiducial inference provides a
possible framework that accommodates this absence of methodology. Under the
fabric of generalized fiducial inference along with sequential Monte Carlo
methods, we present an approach for interval estimation for both balanced and
unbalanced Gaussian linear mixed models. We compare the proposed method to
classical and Bayesian results in the literature in a simulation study of
two-fold nested models and two-factor crossed designs with an interaction term.
The proposed method is found to be competitive or better when evaluated based
on frequentist criteria of empirical coverage and average length of confidence
intervals for small sample sizes. A MATLAB implementation of the proposed
algorithm is available from the authors.Comment: Published in at http://dx.doi.org/10.1214/12-AOS1030 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Financial Inclusion and Financial Stability: Current Policy Issues
The recent financial crisis has shown that financial innovation can have devastating systemic impacts. International standard setters’ and national regulators’ response has been a global concerted effort to overhaul and tighten financial regulations. However, at a time of designing stricter regulations, it is crucial to avoid a backlash against financial inclusion. In this chapter, we argue that greater financial inclusion presents opportunities to enhance financial stability. Our arguments are based on the following insights: - Financial inclusion poses risks at the institutional level, but these are hardly systemic in nature. Evidence suggests that low-income savers and borrowers tend to maintain solid financial behavior throughout financial crises, keeping deposits in a safe place and paying back their loans. - Institutional risk profiles at the bottom end of the financial market are characterized by large numbers of vulnerable clients who own limited balances and transact small volumes. Although this profile may raise some concerns regarding reputational risks for the central bank and consumer protection, in terms of financial instability, the risk posed by inclusive policies is negligible. - In addition, risks prevalent at the institutional level are manageable with known prudential tools and more effective customer protection. - The potential costs of financial inclusion are compensated for by important dynamic benefits that enhance financial stability over time through a deeper and more diversified financial system. In the following pages, we present the current state of financial inclusion globally. We also explore some trends in financial inclusion and what the most effective policies are to favor it. In doing so, we suggest that innovations aimed at countering financial exclusion may help strengthen financial systems rather than weakening them.financial inclusion; financial stability; costs and benefits; current policy issues
Antigen-specific electrophoretic cell separation for immunological investigations
Preincubation of human blood lymphocytes with cell surface antigen specific antibodies under non-capping conditions reduces the electrophoretic mobility of the corresponding lymphocyte subpopulation. Antigen-positive and antigen-negative cells can be separated by free flow electrophoresis with high yield, purity and viability. The use of fluorescence-labelled second antibodies augments the induced decrease in net surface charge density, and allows rapid detection of antigen-positive cells in the fractions of electrophoresis. Carrier-free cell electrophoresis of human peripheral blood lymphocytes after reaction with anti-IgM-antibody or the monoclonal antibodies OKT4 or OKT8, and sandwich staining with tetrarhodamine isothiocyanate-labelled anti-IgG resulted in the large-scale separation of high pure human B and T lymphocyte subpopulations. Their functional integrity was shown in assays of lymphocyte transformation and of antigen-specific induction and regulation of antibody synthesis in vitro. These separate lymphocyte subpopulations are useful tools for immunological investigations. While, for instance, the effects of drugs on human lymphocytes are obscured by coincident changes in cell composition of the peripheral blood tested that do not by themselves reflect whole body immunocompetence, the cell separation and in vitro assays at a defined cell number and cell composition allow the recording of quantitative changes in the function of different cell subpopulations. We studied the influence of the anesthetic thiopental on separated human lymphocyte subsets. In both polyclonal lectin stimulation and in vitro antibody production, thiopental exhibited a noncytotoxic suppression of lymphocyte functions. B-Cells, T-helper and T-suppressor cells were equally affected and showed the same dose response.(ABSTRACT TRUNCATED AT 250 WORDS
Caries Management :The Role of Surface Interactions in De- and Remineralization-Processes
Background: Bioadhesion and surface interactions on enamel are of essential relevance
for initiation, progression and prevention of caries and erosions. Salivary proteins on and within
initial carious and erosive lesions can facilitate or aggravate de- and remineralization. This applies
for the pellicle layer, the subsurface pellicle and for proteins within initial carious lesions. Little is
known about these proteinaceous structures related to initial caries and erosion. Accordingly, there is
a considerable demand for an understanding of the underlying processes occurring at the interface
between the tooth surface and the oral cavity in order to develop novel agents that limit and modulate
caries and erosion. Objectives and findings: The present paper depicts the current knowledge of the
processes occurring at the interface of the tooth surface and the oral fluids. Proteinaceous layers on
dental hard tissues can prevent or aggravate demineralization processes, whereas proteins within
initial erosive or carious lesions might hinder remineralization considerably and restrict the entry
of ions into lesions. Conclusions: Despite the fact that organic–inorganic surface interactions are
of essential relevance for de- and remineralization processes at the tooth surface, there is limited
knowledge on these clinically relevant phenomena. Accordingly, intensive research is necessary to
develop new approaches in preventive dentistry
Perceptions of Bike Sharing in Underserved Communities Within Milwaukee and the Twin Cities
Despite becoming increasingly more popular in cities across North America, many bikeshare systems have received criticism for not reaching minority and low-income populations. Several bikeshare operators have implemented measures to reach these populations including removing financial barriers, placing stations in underserved neighborhoods, and partnering with various community organizations. However, until recently, few have explored how people in these underserved areas perceive bike sharing.
Feedback was solicited from key community partners in Milwaukee, Wisconsin and Minneapolis/St. Paul, Minnesota to better understand how bike sharing is perceived in underserved communities and to determine whether other models could better address the transportation needs of these communities. A total of 26 interviews were conducted with community partner organizations including social service providers, housing authorities, bicycle advocates, transit advocates, institutions of higher education, and other nonprofit organizations.
The study indicated that there is still a great deal of research needed to understand how underserved communities truly perceive bike sharing—or even biking for that matter. However, relationships play a key role in building trust and empowering communities to participate in activities such as biking and bike sharing.
Other entry points to biking and bike sharing such as long-term bicycle loans and biking as recreation (e.g., initial station installations in parks) may be more effective in making the bike more acceptable to community members who wish to realize its benefits. In the long-term, investing in these types of programs may prove more effective in building a bikeshare customer base in underserved communities.
Finally, efforts to provide equitable access to bike sharing need to include targeted activities for women, families, and groups. Evidence suggests that women and families are particularly disenfranchised and excluded from biking and bike sharing opportunities. By making intentional accommodations to include women and families, bicycle advocates and bikeshare operators may realize increased participation from all members of the community.
As a more substantial library around the topic of bike and bikeshare equity emerges, advocates, planners, and bikeshare operators need to ensure that equitable practices are being explored and implemented to the greatest extent possible—particularly in the way underserved communities’ needs are met through inclusion and engagement
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