264 research outputs found
Measuring Individual Risk Attitudes in the Lab: Task or Ask?: An Empirical Comparison
This paper compares two prominent empirical measures of individual risk attitudes - the Holt and Laury (2002) lottery-choice task and the multi-item questionnaire advocated by Dohmen, Falk, Huffman, Schupp, Sunde and Wagner (forthcoming) - with respect to (a) their within-subject stability over time (one year) and (b) their correlation with actual risk-taking behaviour in the lab - here the amount sent in a trust game (Berg, Dickaut, McCabe, 1995). As it turns out, the measures themselves are uncorrelated (both times) and, most importantly, only the questionnaire measure exhibits test-re-test stability ( · =.78), while virtually no such stability is found in the lottery-choice task. In addition, only the questionnaire measure shows the expected correlations with a Big Five personality measure and is correlated with actual risk-taking behaviour. The results suggest that the questionnaire is the more adequate measure of individual risk attitudes for the analysis of behaviour in economic (lab) experiments. Moreover, with respect to trust, the high re-test stability of trust transfers ( ·= .70) further supports the conjecture that trusting behaviour indeed has a component which itself is a stable individual characteristic (Glaeser, Laibson, Scheinkman and Soutter, 2000).Risk attitudes, trust, personality, lab experiments
A numerical model for the calculation of fretting fatigue crack initiation for a smooth line contact
A numerical model for the calculation of fretting fatigue crack initiation in smooth elastic contact is presented. The model is focused on cylinder-on-plane contact and it can be applied in partial and gross slip conditions by using a constant normal force, a reciprocating tangential force and a cyclic bulk stress. The model is based on explicit stress equations, the multi-axial Dang Van and Findley fatigue criteria and a statistical size factor concept. The model allows non-symmetric traction distribution caused by cyclic bulk stress and the calculation of relative tangential surface displacement. The results from the model correlate well with the corresponding FE-results. The model developed is fast
Cyclic behaviour and fatigue of stainless steels
The cyclic stress-strain curve is used for describing a stabilized (averaged) stress-strain response in strainconcentrations. Importantly, it describes the extremes of the stabilized hysteresis loop. This data is needed forestimating fatigue life based on the strain-life method for components subjected to cyclic loading. A typicalapplication for this calculation method is the design of exhaust manifolds and cylinder heads experiencingsevere temperature cycles and thermal straining. Cyclic tests with variable and constant strain amplitude, aswell as tensile tests have been carried out for three materials: 1.4307, 1.4404 and 1.4541 –type commercialstainless steels in order to study the material response. The formation of martensite was measured in the tests.Secondary hardening was observed with all strain amplitudes in 1.4307 and 1.4541 whereas in 1.4404,secondary hardening occurred only with the smallest test amplitude. Also, the fatigue life of 1.4404 tended tobe shorter than that of 1.4307 and 1.4501 in the high cycle fatigue (HCF) regime
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Basic Personal Values Underlie and Give Coherence to Political Values: A Cross National Study in 15 Countries
Do the political values of the general public form a coherent system? What might be the source of coherence? We view political values as expressions, in the political domain, of more basic personal values. Basic personal values (e.g., security, achievement, benevolence, hedonism) are organized on a circular continuum that reflects their conflicting and compatible motivations. We theorize that this circular motivational structure also gives coherence to political values. We assess this theorizing with data from 15 countries, using eight core political values (e.g., free enterprise, law and order) and ten basic personal values. We specify the underlying basic values expected to promote or oppose each political value. We offer different hypotheses for the 12 non-communist and three post-communist countries studied, where the political context suggests different meanings of a basic or political value. Correlation and regression analyses support almost all hypotheses. Moreover, basic values account for substantially more variance in political values than age, gender, education, and income. Multidimensional scaling analyses demonstrate graphically how the circular motivational continuum of basic personal values structures relations among core political values. This study strengthens the assumption that individual differences in basic personal values play a critical role in political thought
Experience of a Preventive Experiment : Spatial Social Mixing in Post-World War II Housing Estates in Helsinki, Finland
The contingent of large housing estates built in the 1960s and 1970s accounts for almost a half of all high-rises in Finland. The primary ideology in their genesis was to combine industrially prefabricated urban housing development with the surrounding forest landscape—together with a policy of spatial social mixing—to prevent social disorder and segregation. These policies seemed to work as intended until the early 1990s, but have since proved to be insufficient. With Western integration and new information and communication-based economic growth, new trends of population differentiation have emerged. As new wealth has moved out to the fringes of cities, the large housing estates have declined socio-economically—and have been enriched ethnically. This differentiation is structurally produced, works through the regional housing market and, as such, is beyond the scope of the preventive policies pursued. Recent attempts at controlling the regional markets and new forms of spatial social mixing have so far proved difficult.The contingent of large housing estates built in the 1960s and 1970s accounts for almost a half of all high-rises in Finland. The primary ideology in their genesis was to combine industrially prefabricated urban housing development with the surrounding forest landscape—together with a policy of spatial social mixing—to prevent social disorder and segregation. These policies seemed to work as intended until the early 1990s, but have since proved to be insufficient. With Western integration and new information and communication-based economic growth, new trends of population differentiation have emerged. As new wealth has moved out to the fringes of cities, the large housing estates have declined socio-economically—and have been enriched ethnically. This differentiation is structurally produced, works through the regional housing market and, as such, is beyond the scope of the preventive policies pursued. Recent attempts at controlling the regional markets and new forms of spatial social mixing have so far proved difficult.Peer reviewe
Level of suicidal intent predicts overall mortality and suicide after attempted suicide: a 12-year follow-up study
BACKGROUND: The aim of this study was to comprehensively examine clinical risk factors, including suicide intent and hopelessness, for suicide and risk of death from all causes after attempted suicide over a 12-year follow-up period. METHODS: A systematic sample of 224 patients from consecutive cases of attempted suicide referred to health care in four Finnish cities between 1 January and 31 July 1990 was interviewed. RESULTS: After 12 years of follow-up 22% of these patients had died, 8% by committing suicide. The only statistically significant risk factor for eventual suicide was high scores on Beck's Suicidal Intention Scale. Male gender, older age, physical illness or disability and high scores on Beck's Suicidal Intention Scale predicted death overall. CONCLUSIONS: Following attempted suicide, high intention to kill oneself is a significant risk factor for both death from all causes and suicide
Adipocyte-specific protein tyrosine phosphatase 1B deletion increases lipogenesis, adipocyte cell size and is a minor regulator of glucose homeostasis
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A multicenter study on Leigh syndrome: Disease course and predictors of survival
Background: Leigh syndrome is a progressive neurodegenerative disorder, associated with primary or secondary dysfunction of the mitochondrial oxidative phosphorylation. Despite the fact that Leigh syndrome is the most common phenotype of mitochondrial disorders in children, longitudinal natural history data is missing. This study was undertaken to assess the phenotypic and genotypic spectrum of patients with Leigh syndrome, characterise the clinical course and identify predictors of survival in a large cohort of patients. Methods. This is a retrospective study of patients with Leigh syndrome that have been followed at eight centers specialising in mitochondrial diseases in Europe; Gothenburg, Rotterdam, Helsinki, Copenhagen, Stockholm, Brussels, Bergen and Oulu. Results: A total of 130 patients were included (78 males; 52 females), of whom 77 patients had identified pathogenic mutations. The median age of disease onset was 7 months, w
The spatio-relational nature of urban innovation systems: Universities, knowledge intensive business service firms, and collaborative networks
The need to better identify the spatio-relational nature of urban innovation systems and spaces is increasingly acknowledged. The aim of this paper, therefore, is to provide an enhanced understanding of the knowledge networks existing between urban Knowledge Intensive Business Services firms (KIBS) and universities, which are often key components of such systems and spaces. Drawing on an analysis of urban KIBS firms and universities in the UK, it is found that the nature of firms, the location in which they are based, and the research intensity of their university partners are important determinants of the spatiality and localisation of the networks they form. The results show that the smallest urban KIBS firms have the highest propensity to engage in local links with universities, suggesting that they rely most significantly on their own urban innovation system for collaborative network ties.
Keywords : innovation systems; urban innovation spaces; knowledge-based development; proximity; networks; KIBS; universities
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