20,721 research outputs found
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UK State Pension Reform in a Public Choice Framework
Social security systems for old age have been explicitly studied in a public choice framework for over 30 years. They illustrate extremely well the problems of allocating economic resources through a system of voting. Pension systems also currently provide some of the most significant threats to the long-term budget positions of developed countries, a point that was made in the Nobel Laureate lecture of Professor James Buchanan. In this paper, we look at the costs and benefits that will be faced by different groups of voters as a result of state pension reform in the UK. It is shown that state pension systems will be very difficult to reform in ways that reduce government provision. However, an exception to this general rule is that reform by raising retirement ages may well be politically feasible. These results are in accordance, not just with theoretical work, but with other empirical work and practical observations
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Towards a Theory of Analytical Behaviour: A Model of Decision-Making in Visual Analytics
This paper introduces a descriptive model of the human-computer processes that lead to decision-making in visual analytics. A survey of nine models from the visual analytics and HCI literature are presented to account for different perspectives such as sense-making, reasoning, and low-level human-computer interactions. The survey examines the people and computers (entities) presented in the models, the divisions of labour between entities (both physical and role-based), the behaviour of both people and machines as constrained by their roles and agency, and finally the elements and processes which define the flow of data both within and between entities. The survey informs the identification of four observations that characterise analytical behaviour - defined as decision-making facilitated by visual analytics: bilateral discourse, divisions of labour, mixed-synchronicity information flows, and bounded behaviour. Based on these principles, a descriptive model is presented as a contribution towards a theory of analytical behaviour. The future intention is to apply prospect theory, a economic model of decision-making under uncertainty, to the study of analytical behaviour. It is our assertion that to apply prospect theory first requires a descriptive model of the processes that facilitate decision-making in visual analytics. We conclude it necessary to measure the perception of risk in future work in order to apply prospect theory to the study of analytical behaviour using our proposed model
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Representation Effects and Loss Aversion in Analytical Behaviour: An Experimental Study into Decision Making Facilitated by Visual Analytics
This paper presents the results of an experiment into the relationship between the representation of data and decision-making. Three hundred participants online, were asked to choose between a series of financial investment opportunities using data presented in line charts. A single dependent variable of investment choice was examined over four levels of varying display conditions and randomised data. Three variations to line chart visualisations provided a controlled factor between subjects divided into three groups; -Ëstandardâ line charts, -Ëtallâ line charts, and one dual-series line chart. The final results revealed a consistent main effect and two other interactions between certain display conditions and decision-making. The findings of this paper are significant to the study visualisation and to the field of visual analytics. This experiment was devised as part of a study into Analytical Behaviour, defined as decision-making facilitated by visual analytics - a new topic that encompasses existing research and real-world applications
Mind-reading versus neuromarketing: how does a product make an impact on the consumer?
Purpose
â This research study aims to illustrate the mapping of each consumerâs mental processes in a market-relevant context. This paper shows how such maps deliver operational insights that cannot be gained by physical methods such as brain imaging.
Design/methodology/approach
â A marketed conceptual attribute and a sensed material characteristic of a popular product were varied across presentations in a common use. The relative acceptability of each proposition was rated together with analytical descriptors. The mental interaction that determined each consumerâs preferences was calculated from the individualâs performance at discriminating each viewed sample from a personal norm. These personal cognitive characteristics were aggregated into maps of demand in the market for subpanels who bought these for the senses or for the attribute.
Findings
â Each of 18 hypothesized mental processes dominated acceptance in at least a few individuals among both sensory and conceptual purchasers. Consumers using their own descriptive vocabulary processed the factors in appeal of the product more centrally. The sensory and conceptual factors tested were most often processed separately, but a minority of consumers treated them as identical. The personal ideal points used in the integration of information showed that consumers wished for extremes of the marketed concept that are technologically challenging or even impossible. None of this evidence could be obtained from brain imaging, casting in question its usefulness in marketing.
Research limitations/implications
â Panel mapping of multiple discriminations from a personal norm fills three major gaps in consumer marketing research. First, preference scores are related to major influences on choices and their cognitive interactions in the mind. Second, the calculations are completed on the individualâs data and the cognitive parameters of each consumerâs behavior are aggregated â never the raw scores. Third, discrimination scaling puts marketed symbolic attributes and sensed material characteristics on the same footing, hence measuring their causal interactions for the first time.
Practical implications
â Neuromarketing is an unworkable proposition because brain imaging does not distinguish qualitative differences in behavior. Preference tests are operationally effective when designed and analyzed to relate behavioral scores to major influences from market concepts and sensory qualities in interaction. The particular interactions measured in the reported study relate to the major market for healthy eating.
Originality/value
â This is the first study to measure mental interactions among determinants of preference, as well as including both a marketed concept and a sensed characteristic. Such an approach could be of great value to consumer marketing, both defensively and creatively
FBG-based fibre-optic current sensors for power systems protection : laboratory evaluation
Conventional differential current unit protection schemes rely on a pair of electronic protection relays that measure current phasors separately at the boundaries of the protected zone. The scheme requires a separate, often optical, communications channel for the sharing of measurement information to enable the timely identification of and reaction to internal faults. The high voltage environment that the transducers must operate in poses a number of engineering problems stemming from the need for electrical isolation and requirement for transformation of high primary system current magnitudes. Additionally, when either the number of relays or distance between relays is increased, timing problems can arise due to the limited bandwidth, speed and changeable latencies of the communication channels and the increased computation requirements. Fibre-optical sensor systems are maturing as a technology and offer a number of advantages over conventional electronic sensor regimes, including the possession of inherent electrical isolation, chemical inertness, immunity to electromagnetic interference, and their small size and serial multiplexing capability. Fibre sensor systems are therefore experiencing increased uptake in industries that operate in harsh environments, such as oil and gas, or where specific requirements such as large step-out distances or resistance to radiation prohibit the use of electronic sensors. The Advanced Sensors Team within the Institute for Energy and Environment has developed fibre-optic point sensors for voltage and electrical current, based on fibre Bragg grating (FBG) technology, that have been applied successfully to power systems diagnostics. With the photonic systems capability to interrogate up to 100 km from source at kHz sample rates with up to 30 sensors in series, it is possible and highly desirable to adapt this technology for use in power systems protection, where immediate applications in unit and distance protection are clear. In this paper, the application of the FBG-based hybrid current sensor system to power systems protection is presented for the first time. Experimental tests of the response of an optical unit protection system to a range of internal and external fault scenarios are also reported. Secondary current inputs to the system are modelled using ATP and injected into the prototype test system via an APTS3 (Advanced Protection Testing System) unit. Fibre sensors, separated optically by 24 km of fibre, provide all measurement information via a single interrogation system situated at one end of the protected zone. Experimental results confirm high performance of the optical unit protection both in terms of sensitivity to internal faults and stability under external fault conditions. Therefore, the systems ability to overcome problems experienced in electronic relaying systems using conventional current sensing technologies is demonstrated. No separate communications channel is required in this configuration, with fault algorithms being deployed only at one location that need not be close to the protected zone. The fibre-optic current sensor systems capacity for long-distance interrogation and high sensor count qualify it for further applications in more complex protection schemes, or over larger distances, where a single fibre could form the basis of highly novel distributed protection schemes. This potential will also be discussed in detail in the paper
Lipid bilayer composition influences small multidrug transporters
Background:
Membrane proteins are influenced by their surrounding lipids. We investigate the effect of bilayer composition on the membrane transport activity of two members of the small multidrug resistance family; the Escherichia coli transporter, EmrE and the Mycobacterium tuberculosis, TBsmr. In particular we address the influence of phosphatidylethanolamine and anionic lipids on the activity of these multidrug transporters. Phosphatidylethanolamine lipids are native to the membranes of both transporters and also alter the lateral pressure profile of a lipid bilayer. Lipid bilayer lateral pressures affect membrane protein insertion, folding and activity and have been shown to influence reconstitution, topology and activity of membrane transport proteins.
Results:
Both EmrE and TBsmr are found to exhibit a similar dependence on lipid composition, with phosphatidylethanolamine increasing methyl viologen transport. Anionic lipids also increase transport for both EmrE and TBsmr, with the proteins showing a preference for their most prevalent native anionic lipid headgroup; phosphatidylglycerol for EmrE and phosphatidylinositol for TBsmr.
Conclusion:
These findings show that the physical state of the membrane modifies drug transport and that substrate translocation is dependent on in vitro lipid composition. Multidrug transport activity seems to respond to alterations in the lateral forces exerted upon the transport proteins by the bilayer
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Design Spaces in Visual Analytics Based on Goals: Analytical Behaviour, Exploratory Investigation, Information Design & Perceptual Tasks
This paper considers a number of perspectives on design spaces in visual analytics and proposes a new set of four design spaces, based on user goals. Three of the user goals are derived from the literature and are categorised under the terms exploratory investigation, perceptual tasks, and information design. The fourth goal is categorised as analytical behaviour; a recently defined term referring to the study of decision-making facilitated by visual analytics. This paper contributes to the literature on decision-making in visual analytics with a survey of real-world applications within the analytical behaviour design space and by providing a new perspective on design spaces. Central to our analysis is the introduction of decision concepts and theories from economics into a visual analytics context. Given the recent interest in decision-making we wanted to understand the emerging topic of analytical behaviour as a design space and found it necessary to look at more than just decision-making to make a valuable contribution. The result is an initial framework suitable for use in the analysis or design of analytical behaviour applications
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