Assessing Importance and Satisfaction Judgments of Intermodal Work Commuters with Electronic Survey Methodology, MTI Report WP 12-01

Recent advances in multivariate methodology provide an opportunity to further the assessment of service offerings in public transportation for work commuting. We offer methodologies that are alternative to direct rating scale and have advantages in the quality and precision of measurement. The alternative of methodology for adaptive conjoint analysis for the measurement of the importance of attributes in service offering is implemented. Rasch scaling methodology is used for the measurement of satisfaction with these attributes. Advantages that these methodologies introduce for assessment of the respective constructs and use of the assessment are discussed. In a first study, the conjoint derived weights were shown to have predictive capabilities in applications to respondent distributions of a fixed total budget to improve overall service offerings. Results with the Rasch model indicate that the attribute measures are reliable and can adequately constitute a composite measure of satisfaction. The Rasch items were also shown to provide a basis to discriminate between privately owned vehicles (POVs) and public transport commuters. Dissatisfaction with uncertainty in travel time and income level of respondents were the best predictors of POV commuting

Assessing Importance and Satisfaction with Factors in Intermodal Work Commuting, Research Report WP 11-02

Users of multiple-mode public transportation were compared to users of privately owned vehicle (POV) transportation in work commuting within two different travel corridors of Santa Clara County, California. In the first corridor, high tech companies were the source of questionnaire respondents; in the second corridor, the respondents were predominately municipal and county office employees. Most intermodal travel in the first corridor was with multiple buses. In the second corridor, commuters who used a bus and light-rail combination were studied. Survey results from the sample of work commuters who faced a multiple bus combination in travel in the High Tech corridor indicate uncertainty, travel time and distance (the distance from residence to initial mode, interface between modes, and from final stop to work location) were rated as more important, but lower in satisfaction by POV commuters than by public transportation commuters. Results of Importance-Satisfaction Analysis (ISA) of ratings indicated that for POV commuters, travel time, uncertainty, and distance were factors in the quadrant of high importance and low satisfaction, which is most relevant managerially. In the ratings of public transportation commuters, wait time was clearly the factor in this quadrant. Cleanliness and uncertainty were lower satisfaction factors close to the boundary of the high importance quadrant. In survey results from a sample of work commuters to an urban city center who faced a light-rail and bus combination, POV commuters rated most factors as more important, but less satisfactory than commuters who used public transportation. The differences of largest magnitude in both importance and satisfaction were in cost, total travel time, and distance. The largest difference between POV and public transportation commuters in this corridor was in cost. Design implications of the studies differ across travel corridors. Whereas in the High Tech corridor, improving factors of wait time, travel time, and uncertainty appear to have a priority over cost for both public and POV work commuters. The results in the Downtown corridor suggest the opposite. For public transportation commuters in this corridor, cost is the most important factor. The differences in results in the comparisons across public transportation commuters and POV commuters in each sample strongly suggest that independent studies of travel corridors with different travel mode alternatives can be informative and have different managerial implications, even when they are within the same county

User Evaluations of Intermodal Travel to Work: Exploratory Studies, Research Report WP 10-03

The general importance of intermodal travel (i.e., travel in which there is a combination of modes to a destination, for example, train or light rail and a bus connection) has been emphasized in extensive congressional hearings and in state and regional spon¬sored transportation studies. Available empirical studies of the use of intermodal travel have predominantly been in cases where travel is across cities or regions. These studies have most often related use of intermodal travel options to distance, time of day and user demographics and user-identified factors and ratings that evaluate these factors. The principal objective of this explor¬atory study is to identify candidate factors that users relate to the public transit options when work travel is within a local corridor. Two focus groups were conducted in each of two travel corridors in Northern California’s Bay Area. Results identify four factors that are reported to be major considerations in user evaluation of intermodal travel to work. The importance of these factors is indicated by their independent identification in each group and the amount of discussion of the factors. The cost of uncertainty in waiting time between connections and the imputed lack of coordination between modes in service offerings were among the predominant factors in the discussions of all groups

Stochastic resonance in the recovery of signal from agent price expectations

Contributions that noise can make to the objective of detecting signal in agent expectations for price in financial markets are examined. Although contrary to most assumptions on exogenous noise in financial markets as increasing both risk and uncertainty in the detection of signal, a basis for the contribution that noise can have to agent objectives in signal detection through stochastic resonance (SR) is well-documented across disciplines. After reviewing foundations for the micro-processing of expectations, a multi-component model of networked agents that includes a component of bounded rational processing and a component that has been cited as generating “herding” behavior in financial markets is offered. The signal-to-noise ratios in the proposed models provide a basis to investigate SR in an application to financial markets. Results with both deterministic and stochastic forms of the proposed model support SR as a process in which randomness can contribute to the recovery of signal in agent expectation. Additionally, predictive models that indicate the sensitivity of the occurrence of SR to the parameters of the models of agent expectations were estimated and cross-validated. The discriminative ability of the models is reported through Area Under the Receiver Operating Curve (AUROC) methodology. These results extend the cross-discipline demonstrations of SR to models of price in financial markets.</p

Introduction to a Theory of Group Structure and Information Exchange

This theoretical paper develops a framework for relationships between group structure and information exchange. Status orders among group members are important in situations that lack well-developed practices for work and clear criteria for evaluating outcomes.Preparation of this manuscript was supported in part by a grant from the National Science Foundation (IS 84/7948)

Analysis of coding variants in the betacellulin gene in type 2 diabetes and insulin secretion in African American subjects

BACKGROUND: Betacellulin is a member of the epidermal growth factor family, expressed at the highest levels predominantly in the pancreas and thought to be involved in islet neogenesis and regeneration. Nonsynonymous coding variants were reported to be associated with type 2 diabetes in African American subjects. We tested the hypotheses that these previously identified variants were associated with type 2 diabetes in African Americans ascertained in Arkansas and that they altered insulin secretion in glucose tolerant African American subjects. METHODS: We typed three variants, exon1 Cys7Gly (C7G), exon 2 Leu44Phe (L44F), and exon 4 Leu124Met (L124M), in 188 control subjects and 364 subjects with type 2 diabetes. We tested for altered insulin secretion in 107 subjects who had undergone intravenous glucose tolerance tests to assess insulin sensitivity and insulin secretion. RESULTS: No variant was associated with type 2 diabetes, and no variant altered insulin secretion or insulin sensitivity. However, an effect on lipids was observed for all 3 variants, and variant L124M was associated with obesity measures. CONCLUSION: We were unable to confirm a role for nonsynonymous variants of betacellulin in the propensity to type 2 diabetes or to impaired insulin secretion

Raising the participation age in historical perspective : Policy learning from the past?

The raising of the participation age (RPA) to 17 in 2013 and 18 in 2015 marks a historic expansion of compulsory education. Despite the tendency of New Labour governments to eschew historical understanding and explanation, RPA was conceived with the benefit of an analysis of previous attempts to extend compulsion in schooling. This paper assesses the value of a historical understanding of education policy. The period from inception to the projected implementation of RPA is an extended one which has crossed over the change of government, from Labour to Coalition, in 2010. The shifting emphases and meanings of RPA are not simply technical issues but connect to profound historical and social changes. An analysis of the history of the raising of the school leaving age reveals many points of comparison with the contemporary situation. In a number of key areas it is possible to gain insights into the ways in which the study of the past can help to comprehend the present: the role of human capital, the structures of education, in curriculum development and in terms of preparations for change

<i>HLA</i> and autoantibodies define scleroderma subtypes and risk in African and European Americans and suggest a role for molecular mimicry

Systemic sclerosis (SSc) is a clinically heterogeneous autoimmune disease characterized by mutually exclusive autoantibodies directed against distinct nuclear antigens. We examined HLA associations in SSc and its autoantibody subsets in a large, newly recruited African American (AA) cohort and among European Americans (EA). In the AA population, the African ancestry-predominant HLA-DRB1*08:04 and HLA-DRB1*11:02 alleles were associated with overall SSc risk, and the HLA-DRB1*08:04 allele was strongly associated with the severe antifibrillarin (AFA) antibody subset of SSc (odds ratio = 7.4). These African ancestry-predominant alleles may help explain the increased frequency and severity of SSc among the AA population. In the EA population, the HLA-DPB1*13:01 and HLA-DRB1*07:01 alleles were more strongly associated with antitopoisomerase (ATA) and anticentromere antibody-positive subsets of SSc, respectively, than with overall SSc risk, emphasizing the importance of HLA in defining autoantibody subtypes. The association of the HLA-DPB1*13:01 allele with the ATA+ subset of SSc in both AA and EA patients demonstrated a transancestry effect. A direct correlation between SSc prevalence and HLA-DPB1*13:01 allele frequency in multiple populations was observed (r = 0.98, P = 3 × 10−6). Conditional analysis in the autoantibody subsets of SSc revealed several associated amino acid residues, mostly in the peptide-binding groove of the class II HLA molecules. Using HLA &#x3B1; / &#x3B2; allelic heterodimers, we bioinformatically predicted immunodominant peptides of topoisomerase 1, fibrillarin, and centromere protein A and discovered that they are homologous to viral protein sequences from the Mimiviridae and Phycodnaviridae families. Taken together, these data suggest a possible link between HLA alleles, autoantibodies, and environmental triggers in the pathogenesis of SSc

One-Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter

Purpose To prospectively assess the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). Materials and Methods At 23 sites, 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, unable to use anticoagulation were enrolled. The primary end point was clinical success, including successful filter deployment, freedom from new symptomatic PE through 60 days before filter bioconversion, and 6-month freedom from filter-related complications. Patients were monitored by means of radiography, computerized tomography (CT), and CT venography to assess filtering configuration through 60 days, filter bioconversion, and incidence of PE and filter-related complications through 12 months. Results Clinical success was achieved in 111 of 114 evaluable patients (97.4%, 95% confidence interval [CI] 92.5%–99.1%). The rate of freedom from new symptomatic PE through 60 days was 100% (n = 129, 95% CI 97.1%–100.0%), and there were no cases of PE through 12 months for either therapeutic or prophylactic indications. Two patients (1.6%) developed symptomatic caval thrombosis during the first month; neither experienced recurrence after successful interventions. There was no filter tilting, migration, embolization, fracture, or caval perforation by the filter, and no filter-related death through 12 months. Filter bioconversion was successful for 95.7% (110/115) at 6 months and for 96.4% (106/110) at 12 months. Conclusions The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 12 months of imaging-intense follow-up