76 research outputs found

    Using big data to understand consumer behaviour on ethical issues

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    The Consumer Data Research Centre (CDRC) was established by the UK Economic and Social Research Council and launched its data services in 2015. The project is led by the University of Leeds and UCL, with partners at the Universities of Liverpool and Oxford. It is working with consumer-related organisations and businesses to open up their data resources to trusted researchers, enabling them to carry out important social and economic research

    Using big data to understand consumer behaviour on ethical issues

    Get PDF
    The Consumer Data Research Centre (CDRC) was established by the UK Economic and Social Research Council and launched its data services in 2015. The project is led by the University of Leeds and UCL, with partners at the Universities of Liverpool and Oxford. It is working with consumer-related organisations and businesses to open up their data resources to trusted researchers, enabling them to carry out important social and economic research

    Testing the stability of utility parameters in repeated best, repeated best-worst and one-off best-worst studies

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    Stated choice (SC) surveys are a key tool for studying travel behaviour and are used to inform policy decisions in many countries. Recently, the best-worst (BW) variant of SC has rapidly increased in popularity in fields as diverse as transport, marketing and health research. A key argument for its implementation has been that it is perceived to be easier for respondents to identify the best and the worst alternative in a choice set compared to identifying the second- or even third best. For elicitation formats asking respondents to consecutively identify the first, second and third best (etc.) alternative, labelled here as repeated best stages, it is well known that utility and scale parameters are generally not stable across the stages. Joint analysis of the responses to each stage may increase the efficiency of the utility and willingness-to-pay parameters (i.e. smaller standard errors), but incorrect inferences may be made if these parameters are not stable across the stages. This paper tests the stability of utility parameters for the repeated BW and one-off BW format. Using data from three different studies, we show that, regardless of the dataset and elicitation format used, the obtained utility parameters and willingness to pay estimates are not stable across stages. The results thereby question the use of BW data in applied work aimed at forecasting and understanding first (best) choices. Our findings thereby contradict recent discussions about potentially beneficial framing effects in BW surveys. The unique presence of corresponding data from a repeated best and repeated BW exercise in one survey highlights the observed rank-orders are highly consistent across the two elicitation formats and that any differences in marginal willingness to pay estimates can be attributed to the imposed econometric model rather than to differences in the behaviour of respondents

    International meta-analysis of stated preference studies of transportation noise nuisance

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    This paper reports the first meta-analysis and most extensive review of stated preference studies of transportation noise nuisance. The meta-analysis is based on a newly compiled data set of 258 values from 49 studies and 23 countries and spanning more than 40 years. Contrast this with the most extensive meta-analysis of the more conventional hedonic pricing approach which includes 53 noise valuations. Moreover, the sample compares favourably with the 444 observations from the very first meta-analysis of the value of travel time savings which is by far the most widely examined parameter in transport planning. A particularly significant finding of the study is that the intertemporal income elasticity is close to one, somewhat larger than the cross-sectional income elasticity typically obtained from individual studies. This demonstrates the importance of distinguishing the effects of 2 income variations that occur over time, which tend to drive policy, from variations across individuals at one point in time, and such findings are typical of those observed in other markets. Importantly, the values derived are transferable across countries and may be used to benchmark existing evidence and provide values in contexts where none exist. Other key results are that values for aircraft noise exceed those for other modes, whilst those exposed to higher noise levels and those who are highly annoyed also have higher values in line with expectations. A wide range of design effects were tested but few were significant and these included the consumer surplus measure, the representation of noise and the context

    Patient Preferences for Pain Management in Advanced Cancer: Results from a Discrete Choice Experiment

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    Background: Pain from advanced cancer remains prevalent, severe and often under-treated. Aim: The aim of this study was to conduct a discrete choice experiment with patients to understand their preferences for pain management services and inform service development. Methods: Focus groups were used to develop the attributes and levels of the discrete choice experiment. The attributes were: waiting time, type of healthcare professional, out-of-pocket costs, side-effect control, quality of communication, quality of information and pain control. Patients completed the discrete choice experiment along with clinical and health-related quality of life questions. Conditional and mixed logit models were used to analyse the data. Results: Patients with cancer pain (n = 221) and within palliative care services completed the survey (45% were female, mean age 64.6 years; age range 21–92 years). The most important aspects of pain management were: good pain control, zero out-of-pocket costs and good side-effect control. Poor or moderate pain control and £30 costs drew the highest negative preferences. Respondents preferred control of side effects and provision of better information and communication, over access to certain healthcare professionals. Those with lower health-related quality of life were less willing to wait for treatment and willing to incur higher costs. The presence of a carer influenced preferences. Conclusions: Outcome attributes were more important than process attributes but the latter were still valued. Thus, supporting self-management, for example by providing better information on pain may be a worthwhile endeavour. However, service provision may need to account for individual characteristics given the heterogeneity in preferences

    A single aromatic residue in transcriptional repressor protein KorA is critical for cooperativity with its co-regulator KorB

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    A central feature of broad host range IncP-1 plasmids is the set of regulatory circuits that tightly control plasmid core functions under steady-state conditions. Cooperativity between KorB and either KorA or TrbA repressor proteins is a key element of these circuits and deletion analysis has implicated the conserved C-terminal domain of KorAand TrbAin this interaction. By NMR we show that KorA and KorB interact directly and identify KorA amino acids that are affected on KorB binding. Studies on mutants showed that tyrosine 84 (or phenylalanine, in some alleles) is dispensable for repressor activity but critical for the specific interaction with KorB in both in vivo reporter gene assays and in vitro electrophoretic mobility shift and co-purification assays. This confirms that direct and specific protein–protein interactions are responsible for the cooperativity observed between KorB and its corepressors and lays the basis for determining the biological importance of this cooperativity

    Values of travel time in Europe: Review and meta-analysis

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    This paper reports the most extensive meta-analysis of values of time yet conducted, covering 3109 monetary valuations assembled from 389 European studies conducted between 1963 and 2011. It aims to explain how valuations vary across studies, including over time and between countries. In addition to the customary coverage of in-vehicle time in review studies, this paper covers valuations of walk time, wait time, service headway, parking space search time, departure time switching, time in congested traffic, schedule delay early and late, mean lateness and the standard deviation of travel time. Valuations are found to vary with type of time, GDP, distance, journey purpose, mode, the monetary numeraire and a number of factors related to estimation. Model output values of time compare favourably with earnings data, replicate well official recommended values obtained from major national studies, and are transferable across countries. These implied monetary values serve as very useful benchmarks against which new evidence can be assessed and the meta-model provides parameters and values for countries and contexts where there is no other such evidence

    Hyperthermophilic Aquifex aeolicus initiates primer synthesis on a limited set of trinucleotides comprised of cytosines and guanines

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    The placement of the extreme thermophile Aquifex aeolicus in the bacterial phylogenetic tree has evoked much controversy. We investigated whether adaptations for growth at high temperatures would alter a key functional component of the replication machinery, specifically DnaG primase. Although the structure of bacterial primases is conserved, the trinucleotide initiation specificity for A. aeolicus was hypothesized to differ from other microbes as an adaptation to a geothermal milieu. To determine the full range of A. aeolicus primase activity, two oligonucleotides were designed that comprised all potential trinucleotide initiation sequences. One of the screening templates supported primer synthesis and the lengths of the resulting primers were used to predict possible initiation trinucleotides. Use of trinucleotide-specific templates demonstrated that the preferred initiation trinucleotide sequence for A. aeolicus primase was 5′-d(CCC)-3′. Two other sequences, 5′-d(GCC)-3′ and d(CGC)-3′, were also capable of supporting initiation, but to a much lesser degree. None of these trinucleotides were known to be recognition sequences used by other microbial primases. These results suggest that the initiation specificity of A. aeolicus primase may represent an adaptation to a thermophilic environment

    Class-specific restrictions define primase interactions with DNA template and replicative helicase

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    Bacterial primase is stimulated by replicative helicase to produce RNA primers that are essential for DNA replication. To identify mechanisms regulating primase activity, we characterized primase initiation specificity and interactions with the replicative helicase for gram-positive Firmicutes (Staphylococcus, Bacillus and Geobacillus) and gram-negative Proteobacteria (Escherichia, Yersinia and Pseudomonas). Contributions of the primase zinc-binding domain, RNA polymerase domain and helicase-binding domain on de novo primer synthesis were determined using mutated, truncated, chimeric and wild-type primases. Key residues in the β4 strand of the primase zinc-binding domain defined class-associated trinucleotide recognition and substitution of these amino acids transferred specificity across classes. A change in template recognition provided functional evidence for interaction in trans between the zinc-binding domain and RNA polymerase domain of two separate primases. Helicase binding to the primase C-terminal helicase-binding domain modulated RNA primer length in a species-specific manner and productive interactions paralleled genetic relatedness. Results demonstrated that primase template specificity is conserved within a bacterial class, whereas the primase–helicase interaction has co-evolved within each species

    New appraisal values of travel time saving and reliability in Great Britain

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    © 2017, The Author(s). This paper provides an overview of the study ‘Provision of market research for value of time savings and reliability’ undertaken by the Arup/ITS Leeds/Accent consortium for the UK Department for Transport (DfT). The paper summarises recommendations for revised national average values of in-vehicle travel time savings, reliability and time-related quality (e.g. crowding and congestion), which were developed using willingness-to-pay (WTP) methods, for a range of modes, and covering both business and non-work travel purposes. The paper examines variation in these values by characteristics of the traveller and trip, and offers insights into the uncertainties around the values, especially through the calculation of confidence intervals. With regards to non-work, our recommendations entail an increase of around 50% in values for commute, but a reduction of around 25% for other non-work—relative to previous DfT ‘WebTAG’ guidance. With regards to business, our recommendations are based on WTP, and thus represent a methodological shift away from the cost saving approach (CSA) traditionally used in WebTAG. These WTP-based business values show marked variation by distance; for trips of less than 20miles, values are around 75% lower than previous WebTAG values; for trips of around 100miles, WTP-based values are comparable to previous WebTAG; and for longer trips still, WTP-based values exceed those previously in WebTAG
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