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History Analysis (history + analysis)
Kinds of History Analysis Selected AbstractsSurvival and Event History Analysis: A Process Point of View by Odd O. Aalen, Ørnulf Borgan, Håkon K. GjessingINTERNATIONAL STATISTICAL REVIEW, Issue 3 2009Jayanta K. Ghosh No abstract is available for this article. [source] Survival and Event History Analysis: A Process Point of View by AALEN, O. O., BORGAN, O., and GJESSING, H. K.BIOMETRICS, Issue 2 2009Patricia Grambsch No abstract is available for this article. [source] Seismic performance evaluation of a 34-story steel building retrofitted with response modification elementsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 6 2009Yuan-Tao Weng Abstract The original structural design of this case study consisted of five basement floors and a 34-story hotel tower in Kaohsiung, Taiwan. The construction started in 1993, and the erection of the entire steel frame and the pouring of concrete slabs up to the 26th floor were completed before 1996. However, construction of the original hotel was subsequently suspended for 10 years. Recently, this building has been retrofitted for residential purposes. Buckling restrained braces (BRBs) and eccentrically braced frames were incorporated into the seismic design of the new residential tower. This paper presents the seismic resisting structural system, seismic design criteria, full-scale test results of one BRB member and the as-built welded moment connections. Test results confirm that the two side web-plate stiffening details can effectively improve the rotational capacity of welded moment connection. The paper also discusses the analytical models for simulating the experimental responses of the BRB members and the welded moment connections. Nonlinear response history analyses (NLRHA) indicate that the inelastic deformational demands of the original and the redesigned structures induced by the maximum considered earthquakes are less than those found in the seismic building codes or laboratory tests. This paper also proposes a ground motion scaling method considering multi-mode effects for NLRHA of the example building. It is shown that the proposed scaling method worked well in reducing the scatter in estimated peak seismic demands. Copyright © 2008 John Wiley & Sons, Ltd. [source] Bench,shelf system dynamic characteristics and their effects on equipment and contentsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 13 2006Tara C. Hutchinson Abstract Economic losses during past earthquakes are strongly associated with damage and failure to nonstructural equipment and contents. Among the vast types of nonstructural elements, one important category, is scientific equipment in biological or chemical laboratories. These equipment are often mounted on heavy ceramic bench-tops of bench,shelf systems, which in turn may amplify the dynamic motions imposed. To investigate the seismic response of these types of systems, a series of shake table and field experiments were conducted considering different representative bench and shelf-mounted equipment and contents. Results from shake table experiments indicate that these equipment are generally sliding-dominated. In addition, the bench,shelf system is observed to be very stiff and when lightly loaded, has a fundamental frequency between 10 and 16 Hz. An approximate 50% reduction in the first and second fundamental frequencies is observed considering practical loading conditions. Insight into a broader range of system response is provided by conducting eigenvalue and time history analyses. Non-linear regression through the numerical data indicate acceleration amplification ratios , range from 2.6 to 1.4 and from 4.3 to 1.6, for fixed,fixed and pinned,pinned conditions, respectively. Both the experimental and numerical results support the importance of determining the potential dynamic amplification of motion in the context of accurately determining the maximum sliding displacement of support equipment and contents. Copyright © 2006 John Wiley & Sons, Ltd. [source] Evaluation of the influence of vertical irregularities on the seismic performance of a nine-storey steel frameEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2006Fragiadakis Michalis Abstract A methodology based on incremental dynamic analysis (IDA) is presented for the evaluation of structures with vertical irregularities. Four types of storey-irregularities are considered: stiffness, strength, combined stiffness and strength, and mass irregularities. Using the well-known nine-storey LA9 steel frame as a base, the objective is to quantify the effect of irregularities, both for individual and for combinations of stories, on its response. In this context a rational methodology for comparing the seismic performance of different structural configurations is proposed by means of IDA. This entails performing non-linear time history analyses for a suite of ground motion records scaled to several intensity levels and suitably interpolating the results to calculate capacities for a number of limit-states, from elasticity to final global instability. By expressing all limit-state capacities with a common intensity measure, the reference and each modified structure can be naturally compared without needing to have the same period or yield base shear. Using the bootstrap method to construct appropriate confidence intervals, it becomes possible to isolate the effect of irregularities from the record-to-record variability. Thus, the proposed methodology enables a full-range performance evaluation using a highly accurate analysis method that pinpoints the effect of any source of irregularity for each limit-state. Copyright © 2006 John Wiley & Sons, Ltd. [source] From Soviet Modernization to Post,Soviet Transformation: Understanding Marriage and Fertility Dynamics in UzbekistanDEVELOPMENT AND CHANGE, Issue 3 2003Victor Agadjanian In this article we analyse the dynamics of marriage and childbearing in Uzbekistan through the prism of the recent socioeconomic and political history of that country. After becoming an independent nation in 1991, Uzbekistan abandoned the Soviet modernization project and aspired to set out on a radically different course of economic, social, and political development. We argue, however, that not only independence but also the preceding period of perestroika reforms (1985,91) had a dramatic effect on social conditions and practices and, consequently, the demographic behaviour of the country's population. Using data from the 1996 Uzbekistan Demographic and Health Survey we apply event,history analysis to examine changes in the timing of entry into first marriage, first and second births over four periods: two periods of pre,perestroika socialism, the perestroika years, and the period since independence. We investigate the factors that influenced the timing of these events in each of the four periods among Uzbeks, the country's eponymous and largest ethnic group, and among Uzbekistan's urban population. In general, our results point to a dialectic combination of continuity and change in Uzbekistan's recent demographic trends, which reflect the complex and contradictory nature of broader societal transformations in that and other parts of the former Soviet Union. [source] Evaluation of simplified methods of analysis for structures with triple friction pendulum isolatorsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 1 2010Fabio Fadi Abstract Triple friction pendulum isolators, that exhibit behavior with amplitude-dependent strength and instantaneous stiffness, represent a new development in seismic isolation. The application of simplified methods of analysis for this type of seismically isolated structures requires development of tools of simplified analysis and demonstration of their accuracy. This paper describes these tools and presents validation studies based on a large number of nonlinear response history analysis results. It is shown that simplified methods of analysis systematically provide good and often conservative estimates of isolator displacement demands and good estimates of isolator peak velocities. Copyright © 2009 John Wiley & Sons, Ltd. [source] Rigid-plastic models for the seismic design and assessment of steel framed structuresEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 14 2009C. Málaga-Chuquitaype Abstract This paper demonstrates the applicability of response history analysis based on rigid-plastic models for the seismic assessment and design of steel buildings. The rigid-plastic force,deformation relationship as applied in steel moment-resisting frames (MRF) is re-examined and new rigid-plastic models are developed for concentrically-braced frames and dual structural systems consisting of MRF coupled with braced systems. This paper demonstrates that such rigid-plastic models are able to predict global seismic demands with reasonable accuracy. It is also shown that, the direct relationship that exists between peak displacement and the plastic capacity of rigid-plastic oscillators can be used to define the level of seismic demand for a given performance target. Copyright© 2009 John Wiley & Sons, Ltd. [source] Seismic behaviour of self-centring braced frame buildings with reusable hysteretic damping braceEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2007Songye Zhu Abstract This paper presents the seismic behaviour of a concentrically braced frame system with self-centring capability, in which a special type of bracing element termed reusable hysteretic damping brace (RHDB) is used. The RHDB is a passive energy dissipation device with its core energy-dissipating component made of superelastic Nitinol wires. Compared with conventional bracing in steel structures, RHDB has a few prominent performance characteristics: damage free under frequent and design basis earthquakes in earthquake prone areas; minimal residual drifts due to the self-centring capability of RHDB frame; and ability to survive several strong earthquakes without the need for repair or replacement. This paper also includes a brief discussion of the RHDB's mechanical configuration and analytical model for RHDB. The seismic performance study of RHDB frame was carried out through a non-linear time history analysis of 3-storey and 6-storey RHDB frame buildings subjected to two suites of 20 earthquake ground motions. The analysis results were compared with buckling-restrained brace (BRB) frames. This study shows that RHDB frame has a potential to outperform BRB frames by eliminating the residual drift problem. Copyright © 2007 John Wiley & Sons, Ltd. [source] Simplified seismic analysis of asymmetric building systemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2007Jui-Liang Lin Abstract The paper reviews the uncoupled modal response history analysis (UMRHA) and modal pushover analysis (MPA) procedure in the analysis of asymmetric structures. From the pushover curves in ADRS format, showing the relationships of base shear versus roof translation and base torque versus roof rotation, a bifurcating characteristic of the pushover curves of an asymmetric structure is observed. A two-degree-of-freedom (2DOF) modal stick is constructed using lump mass eccentrically placed at the end of beam which is connected with the column by a rotational spring. By converting the equation of motion of a whole structure into 2DOF modal equations, all of the elastic properties in the 2DOF modal sticks can be determined accurately. A mathematical proof is carried out to demonstrate that the 2DOF modal stick is consistent with the single-degree-of-freedom (SDOF) modal stick at elastic state. The bifurcating characteristic of modal pushover curves and the interaction of modal translation and rotation can be considered rationally by this 2DOF modal stick. In order to verify the effectiveness of this proposed 2DOF modal stick, a two-storey asymmetric building structure was analysed by the UMRHA procedure incorporating this novel 2DOF modal sticks (2DMPA) and conventional SDOF modal sticks (SDMPA), respectively. The analytical results are compared with those obtained by nonlinear response history analysis (RHA). It is illustrated that the accuracy of the rotational response histories obtained by 2DMPA is much better than those obtained by SDMPA. Consequently, the estimations of translational response histories on flexible side (FS) and stiff side (SS) of the building structure are also improved. Copyright © 2006 John Wiley & Sons, Ltd. [source] Resource allocation-based life histories: A conceptual basis for studies of ecological toxicology,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2001Justin D. Congdon Abstract Whereas ecological assessments of contaminants are concerned with populations and higher levels of organization, most mechanistic work in toxicology is directed at effects on individuals and their parts. We propose that studies based on individuals can be useful in ecological analysis of polluted systems when based on the concepts of resource allocation-based life history analysis. At the heart of the resource allocation approach is the concept of operative environments of individuals (i.e., environmental factors influencing birth, death, or migration). Contaminants can have strong influences on operative environments, modifying resource allocation strategies that reflect changes in energy assimilation and demands. By examining contaminant-induced responses of individuals from the perspective of changing operative environments, individual-based changes and population dynamics can be addressed in an ecologically rigorous manner. [source] Cumulative adversity and drug dependence in young adults: racial/ethnic contrastsADDICTION, Issue 3 2003R. Jay Turner ABSTRACT Aims To study cumulative exposure to stressors as a risk factor for drug dependence, and evaluate whether group differences in exposure contribute to differences in prevalence. Design Cross-sectional community survey of life-time adverse experiences and substance and psychiatric disorders. Setting Data collected between 1997 and 2000 in Miami,Dade County, USA. Participants A total of 1803 former Miami,Dade public school students, 93% between ages 19 and 21 years when interviewed. Males and females of Cuban origin, other Caribbean basin Hispanics, African-Americans and non-Hispanic whites are represented equally. Measurements Drug dependence disorder assessed by DSM-IV criteria using the Composite International Diagnostic Interview, and a 41-item checklist of life-time exposure to major and potentially traumatic experiences. Both measures include age at time of first occurrence. Findings Life-time rate of drug dependence disorder (total 14.3%) did not vary significantly (P > 0.05) by socio-economic group. Male rate (17.6%) was significantly greater than female rate (10.9%). The African-American rate (6.5%) was dramatically lower than non-Hispanic white (17.0%), Cuban (18.1%) and non-Cuban Hispanic (16.0%) rates despite their dramatically higher exposure to adversity. Twenty-eight of 33 individual adversities were associated with the subsequent onset of drug dependence (P < 0.05). Cumulative life-time exposure was greatest for males and for African-Americans, and was associated inversely with socio-economic level. Multivariate discrete-time event history analysis revealed significant independent effects of distal (>1 year earlier) and proximal (previous year) exposure to adverse events (P < 0.05), controlling for childhood conduct disorder, attention deficit hyperactive disorder and previous psychiatric disorder. Conclusions Life-time cumulative exposure to distant as well as more recent adversity predicts risk of subsequent drug dependence, although it does not explain ethnic group differences in risk. [source] Shaky attachments: Individual-level stability and change of partisanship among West German voters, 1984,2001EUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 4 2006RÜDIGER SCHMITT-BECK In this article, the authors take advantage of a unique longitudinal database , the German Socio-Economic Panel (GSOEP) , to test the basic premise of partisanship's high persistence. Analysing individual-level data from 18 annual panel waves conducted in West Germany between 1984 and 2001, it was found that only a minority of the electorate appears steadfast with regard to partisanship over the entire period. Using event history analysis, the authors demonstrate how movements from partisanship into independence and changes between parties are affected by: personal attributes of voters, especially cognitive mobilisation; by properties of their social contexts, in particular spousal relationships and family constellations; by situational contexts, specifically election campaigns; and by the type of party with which voters identify. [source] An efficient time-domain damping solvent extraction algorithm and its application to arch dam,foundation interaction analysisINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 9 2008Hong Zhong Abstract The dynamic structure,unbounded foundation interaction plays an important role in the seismic response of structures. The damping solvent extraction (DSE) method put forward by Wolf and Song has a great advantage of simplicity, with no singular integrals to be evaluated, no fundamental solution required and convolution integrals avoided. However, implementation of DSE in the time domain to large-scale engineering problems is associated with enormous difficulties in evaluating interaction forces on the structure,unbounded foundation interface, because the displacement on the corresponding interface is an unknown vector to be found. Three sets of interrelated large algebraic equations have to be solved simultaneously. To overcome these difficulties, an efficient algorithm is presented, such that the solution procedure can be greatly simplified and computational effort considerably saved. To verify its accuracy, two examples with analytical solutions were investigated, each with a parameter analysis on the domain size and amount of artificial damping. Then with the parameters suggested in the parameter study, the complex frequency,response functions and earthquake time history analysis of Morrow Point dam were presented to demonstrate the applicability and efficiency of DSE approach. Copyright © 2007 John Wiley & Sons, Ltd. [source] Transnational Networks and Policy Diffusion: The Case of Gender MainstreamingINTERNATIONAL STUDIES QUARTERLY, Issue 1 2001Jacqui True How can we account for the global diffusion of remarkably similar policy innovations across widely differing nation-states? In an era characterized by heightened globalization and increasingly radical state restructuring, this question has become especially acute. Scholars of international relations offer a number of theoretical explanations for the cross-national convergence of ideas, institutions, and interests. We examine the proliferation of state bureaucracies for gender mainstreaming. These organizations seek to integrate a gender-equality perspective across all areas of government policy. Although they so far have received scant attention outside of feminist policy circles, these mainstreaming bureaucracies,now in place in over 100 countries,represent a powerful challenge to business-as-usual politics and policymaking. As a policy innovation, the speed with which these institutional mechanisms have been adopted by the majority of national governments is unprecedented. We argue that transnational networks composed largely of nonstate actors (notably women's international nongovernmental organizations and the United Nations) have been the primary forces driving the diffusion of gender mainstreaming. In an event history analysis of 157 nation-states from 1975 to 1998, we assess how various national and transnational factors have affected the timing and the type of the institutional changes these states have made. Our findings support the claim that the diffusion of gender-mainstreaming mechanisms has been facilitated by the role played by transnational networks, in particular by the transnational feminist movement. Further, they suggest a major shift in the nature and the locus of global politics and national policymaking. [source] Perceptions about services and dropout from a substance abuse case management programJOURNAL OF COMMUNITY PSYCHOLOGY, Issue 5 2007Michael R. Sosin This article uses event history analysis to examine certain determinants of dropout from a case management program that serves homeless adults with substance abuse problems. The examined determinants are perceptions of conventional treatment services: (a) client perceptions concerning the value of the conventional services that case managers help them to obtain, (b) the views of use services held by social contacts, and (c) client perceptions of the legitimacy of conventional services. The findings, some of which involve statistical interactions, suggest that clients drop out of case management services more slowly (a) when they favor pursuit of particularly efficacious conventional programs; (b) when they find conventional programs to be of low legitimacy; (c) when, under special conditions, they perceive that conventional services are less caring; or (d) when social contracts do not pressure them. These findings generally imply that clients look to case management services when they are more skeptical about conventional services. The variables predicting dropout from case management poorly predict continuation in conventional substance abuse services, indicating that dropout is linked to perceptions of services in context-specific ways. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 583,602, 2007. [source] The Substitution Hypothesis: The Impact of Premarital Liaisons and Human Capital on Marital TimingJOURNAL OF MARRIAGE AND FAMILY, Issue 2 2002Monica Gaughan Nonmarital romantic and sexual relationships occur concurrently with the human capital acquisition process and contribute to delaying or forgoing marriage. Event history analysis is used to model the marital hazard rate of 341 White women born between 1960 and 1963 in a Western metropolitan area. In addition to family background, adolescent characteristics, and employment and educational histories, the structure of the women's premarital liaisons is shown to play an important role in the timing of first marriage. The greater a woman's involvement in nonmarital romantic and sexual activity, the less likely she is to be married by age 27,30. Human capital characteristics and the dynamics of relationship histories operate independently to explain marital timing. This supports the theory that women substitute premarital liaisons for marriage early in the adult life course. However, there is no evidence that highly educated women, or those who are students, are more or less likely to do so than others. [source] Changes in Wives' Income: Effects on Marital Happiness, Psychological Well-Being, and the Risk of DivorceJOURNAL OF MARRIAGE AND FAMILY, Issue 2 2001Stacy J. Rogers We investigate the effects of increases in married women's actual income and in their proportion of total family income on marital happiness, psychological well-being, and the likelihood of divorce. We use data from a sample of 1,047 married individuals (not couples) in medium-duration marriages, drawn from a five-wave panel survey begun in 1980 and continuing to 1997. Structural equation modeling is used to assess the impact of increases in married women's absolute and relative income from 1980 to 1988 on the marital happiness and well-being of married men and women in 1988. Event history analysis is used to determine how these changes affect the risk of divorce between 1988 and 1997. We find that increases in married women's absolute and relative income significantly increase their marital happiness and well-being. Increases in married women's absolute income generally have nonsignificant effects for married men. However, married men's well-being is significantly lower when married women's proportional contributions to the total family income are increased. The likelihood of divorce is not significantly affected by increases in married women's income. Nevertheless, increases in married women's income may indirectly lower the risk of divorce by increasing women's marital happiness. [source] Nonparametric maximum likelihood estimation for shifted curvesJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 2 2001Birgitte B. Rønn The analysis of a sample of curves can be done by self-modelling regression methods. Within this framework we follow the ideas of nonparametric maximum likelihood estimation known from event history analysis and the counting process set-up. We derive an infinite dimensional score equation and from there we suggest an algorithm to estimate the shape function for a simple shape invariant model. The nonparametric maximum likelihood estimator that we find turns out to be a Nadaraya,Watson-like estimator, but unlike in the usual kernel smoothing situation we do not need to select a bandwidth or even a kernel function, since the score equation automatically selects the shape and the smoothing parameter for the estimation. We apply the method to a sample of electrophoretic spectra to illustrate how it works. [source] Effects of pets on asthma development up to 8 years of age: the PIAMA studyALLERGY, Issue 8 2009M. Kerkhof Background:, Recall bias may provide discrepant relationships of pet exposure with sensitization and asthma development. We studied prospectively effects of pets at home on development of sensitization, asthma and respiratory symptoms from birth up to age 8 years. Methods:, Event history analysis was performed on annually registered data of 2951 children, participating in the PIAMA birth cohort study. Results:, Children with a cat or dog at home at 3 months of age had a significantly lower prevalence of sensitization to inhalant allergens at age 8, but not of asthma. A cat decreased the risk of house dust mite sensitization at age 8 [odds ratio (OR) = 0.68, 95% confidence interval (CI) 0.49,0.95], a dog of pollen sensitization (OR = 0.49, 95% CI: 0.29,0.83). A cat or dog at home did not significantly affect asthma incidence in each subsequent year. From 2 years of age onwards, the incidence of wheeze (OR = 1.52, 95% CI: 1.12,2.05) and a dry cough at night (OR = 1.28, 95% CI: 1.05,1.57) was higher in children with a dog, whereas removal of a dog increased the risk of developing asthma symptoms. Comparing analyses using prospectively and retrospectively collected data on diagnosed asthma showed important recall bias. Conclusions:, Our prospective study shows a protective effect of early presence of pets at home on sensitization to inhalant allergens, but no prevention of asthma development. Furthermore, children with pets had more frequent transient or intermittent asthma symptoms. Parental report of asthma by recall may provide spurious results of these associations. [source] Kolmogorov,Smirnov-type testing for the partial homogeneity of Markov processes,with application to credit riskAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 3 2007Rafael Weißbach Abstract In banking, the default behaviour of the counterpart is not only of interest for the pricing of transactions under credit risk but also for the assessment of a portfolio credit risk. We develop a test against the hypothesis that default intensities are chronologically constant within a group of similar counterparts, e.g. a rating class. The Kolmogorov,Smirnov-type test builds up on the asymptotic normality of counting processes in event history analysis. The right censoring accommodates for Markov processes with more than one no-absorbing state. A simulation study and two examples of rating systems demonstrate that partial homogeneity can be assumed, however occasionally, certain migrations must be modelled and estimated inhomogeneously. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||