46 research outputs found

    Bayes and health care research.

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    Bayes’ rule shows how one might rationally change one’s beliefs in the light of evidence. It is the foundation of a statistical method called Bayesianism. In health care research, Bayesianism has its advocates but the dominant statistical method is frequentism. There are at least two important philosophical differences between these methods. First, Bayesianism takes a subjectivist view of probability (i.e. that probability scores are statements of subjective belief, not objective fact) whilst frequentism takes an objectivist view. Second, Bayesianism is explicitly inductive (i.e. it shows how we may induce views about the world based on partial data from it) whereas frequentism is at least compatible with non-inductive views of scientific method, particularly the critical realism of Popper. Popper and others detail significant problems with induction. Frequentism’s apparent ability to avoid these, plus its ability to give a seemingly more scientific and objective take on probability, lies behind its philosophical appeal to health care researchers. However, there are also significant problems with frequentism, particularly its inability to assign probability scores to single events. Popper thus proposed an alternative objectivist view of probability, called propensity theory, which he allies to a theory of corroboration; but this too has significant problems, in particular, it may not successfully avoid induction. If this is so then Bayesianism might be philosophically the strongest of the statistical approaches. The article sets out a number of its philosophical and methodological attractions. Finally, it outlines a way in which critical realism and Bayesianism might work together. </p

    Community Policing: Broken Windows, Community Building, and Satisfaction with the Police

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    The concept of community policing dominates the law enforcement profession today. One would be hard pressed to find an advertisement for a police chief’s position that does not require a thorough understanding of this method of policing. Like the Kansas City preventive patrol experiment and the Rand report on the criminal investigation process, the call for community policing has led to dramatic changes in the way that police carry out their responsibilities. In spite of its popularity, there have been a number of challenges to community policing from social scientists who are particularly concerned about the ‘broken windows’ model of policing. These challenges have not been received well by the law enforcement community, which argues that sociologists are wedded to the idea that crime is caused by the structural features of capitalist society, including economic injustice, racism, and poverty. The purpose of this article is to bridge the gap between these two positions. Yes, there is a place for community policing, and, yes, social problems do contribute to crime. The article starts by reviewing the development of community policing in the United States. An analysis of the theoretical constructs that support community policing then follows. Finally, we argue that there is sound theoretical evidence to support community policing, particularly those programmes that improve citizen satisfaction with the manner in which police carry out their responsibilities

    Earth Observation Technologies: Low-End-Market Disruptive Innovation

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    After decades of traditional space businesses, the space paradigm is changing. New approaches to more efficient missions in terms of costs, design, and manufacturing processes are fostered. For instance, placing big constellations of micro- and nano-satellites in Low Earth Orbit and Very Low Earth Orbit (LEO and VLEO) enables the space community to obtain a huge amount of data in near real-time with an unprecedented temporal resolution. Beyond technology innovations, other drivers promote innovation in the space sector like the increasing demand for Earth Observation (EO) data by the commercial sector. Perez et al. stated that the EO industry is the second market in terms of operative satellites (661 units), micro- and nano-satellites being the higher share of them (61%). Technological and market drivers encourage the emergence of new start-ups in the space environment like Skybox, OneWeb, Telesat, Planet, and OpenCosmos, among others, with novel business models that change the accessibility, affordability, ownership, and commercialization of space products and services. This chapter shows some results of the H2020 DISCOVERER (DISruptive teChnOlogies for VERy low Earth oRbit platforms) Project and focuses on understanding how micro- and nano-satellites have been disrupting the EO market in front of traditional platforms

    Socio-economic differences and health seeking behaviour for the diagnosis and treatment of malaria: a case study of four local government areas operating the Bamako initiative programme in south-east Nigeria

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    BACKGROUND: Malaria is one of the leading causes of mortality and morbidity in Nigeria. It is not known how user fees introduced under the Bamako Initiative (BI) system affect healthcare seeking among different socio-economic groups in Nigeria for diagnosis and treatment of malaria. Reliable information is needed to initiate new policy thrusts to protect the poor from the adverse effect of user fees. METHODS: Structured questionnaires were used to collect information from 1594 female household primary care givers or household head on their socio-economic and demographic status and use of malaria diagnosis and treatment services. Principal components analysis was used to create a socio-economic status index which was decomposed into quartiles and chi-square for trends was used to calculate for any statistical difference. RESULTS: The study showed that self diagnosis was the commonest form of diagnosis by the respondents. This was followed by diagnosis through laboratory tests, community health workers, family members and traditional healers. The initial choice of care for malaria was a visit to the patent medicine dealers for most respondents. This was followed by visit to the government hospitals, the BI health centres, traditional medicine healers, private clinics, community health workers and does nothing at home. Furthermore, the private health facilities were the initial choice of treatment for the majority with a decline among those choosing them as a second source of care and an increase in the utilization of public health facilities as a second choice of care. Self diagnosis was practiced more by the poorer households while the least poor used the patent medicine dealers and community health workers less often for diagnosis of malaria. The least poor groups had a higher probability of seeking treatment at the BI health centres (creating equity problem in BI), hospitals, and private clinics and in using laboratory procedures. The least poor also used the patent medicine dealers and community health workers less often for the treatment of malaria. The richer households complained more about poor staff attitude and lack of drugs as their reasons for not attending the BI health centres. The factors that encourage people to use services in BI health centres were availability of good services, proximity of the centres to the homes and polite health workers. CONCLUSIONS: Factors deterring people from using BI centres should be eliminated. The use of laboratory services for the diagnosis of malaria by the poor should be encouraged through appropriate information, education and communication which at the long run will be more cost effective and cost saving for them while devising means of reducing the equity gap created. This could be done by granting a properly worked out and implemented fee exemptions to the poor or completely abolishing user fees for the diagnosis and treatment of malaria in BI health centres

    Morphing images: a potential tool for teaching word recognition to children with severe learning difficulties

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    Children with severe learning difficulties who fail to begin word recognition can learn to recognise pictures and symbols relatively easily. However, finding an effective means of using pictures to teach word recognition has proved problematic. This research explores the use of morphing software to support the transition from picture to word recognition. Morphing software was used to teach word recognition to a group of eight children who were previously unable to recognise words. At the end of 16 teaching sessions, in a related design, the morphing technique was more effective than a word-alone approach ( p< 0.05, one-tailed). These results support the use of techniques such as symbol accentuation (Miller & Miller, 1971) and challenge the concept that the use of pictorial information is inherently detrimental to learning in this context, in comparison to the repeated presentation of words alone. The recent advent of accessible morphing software removes previous barriers to this type of approach. The investigation highlights several useful avenues for future research, in particular, the use of mnemonic elements within morphing teaching methods

    Subband electronic temperatures and electron-lattice energyrelaxation in THz QCLs with different coduction band offsets

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    The electronic temperatures of the conduction subbands, the local lattice temperature, and the electron-lattice energy relaxation times E in bound-to-continuum GaAs/AlxGa1−xAs quantum cascade lasers, operating at 2.9 and 2 THz, are reported. This information has been gathered from the analysis of microprobe photoluminescence spectra collected during device continuous wave operation. We find that the electronic distributions in both the active region and the injector are thermalized and that all subbands share the same electronic temperature. The efficiency of electron cooling increases with the conduction band offset
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