Sökning: "instrumental variable"

Visar resultat 16 - 20 av 64 avhandlingar innehållade orden instrumental variable.

  1. 16. Methods for improving covariate balance in observational studies

    Författare :Philip Fowler; Xavier de Luna; Ingeborg Waernbaum; Martin Huber; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; causal effect; coarsening; discretisation; proxy variables; register study; swedish social insurance agency; unobserved variables;

    Sammanfattning : This thesis contributes to the field of causal inference, where the main interest is to estimate the effect of a treatment on some outcome. At its core, causal inference is an exercise in controlling for imbalance (differences) in covariate distributions between the treated and the controls, as such imbalances otherwise can bias estimates of causal effects. LÄS MER

  3. 17. Factors influencing prognosis in acute coronary syndrome - A report from the SWEDEHEART registry

    Författare :Oskar Angerås; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Acute coronary syndrome; acute myocardial infarction; risk factors; obesity paradox; socioeconomic status; cardiogenic shock; thrombus aspiration; SWEDEHEART; SCAAR; RIKS-HIA;

    Sammanfattning : Background: Acute coronary syndrome (ACS) is one of the major causes of mortality in the world. The prognosis for patients with ACS is affected by several factors, such as baseline characteristics and treatment before, during and after hospitalisation. . LÄS MER

  4. 18. Graybox Modelling of Ships Using Indirect Input Measurements

    Författare :Jonas Linder; Martin Enqvist; Fredrik Gustafsson; Johan Sjöberg; Magnus Mossberg; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : A ship's roll dynamics is very sensitive to changes in the loading conditions and a worst-case scenario is that the ship will capsize. Actually, the mass and center of mass are two of the most influential parameters in most mechanical systems. LÄS MER

  5. 19. Essays on Estimation Methods for Factor Models and Structural Equation Models

    Författare :Shaobo Jin; Fan Yang-Wallentin; Rolf Larsson; Li Cai; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; shrinkage; factor rotation; penalized maximum likelihood; pseudo-maximum likelihood; multi-group analysis; ordinal data; robustness; Statistics; Statistik;

    Sammanfattning : This thesis which consists of four papers is concerned with estimation methods in factor analysis and structural equation models. New estimation methods are proposed and investigated.In paper I an approximation of the penalized maximum likelihood (ML) is introduced to fit an exploratory factor analysis model. LÄS MER

  7. 20. Estimation of Nonlinear Greybox Models for Marine Applications

    Författare :Fredrik Ljungberg; Martin Enqvist; Svante Gunnarsson; Håkan Hjalmarsson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : As marine vessels are becoming increasingly autonomous, having accurate simulation models available is turning into an absolute necessity. This holds both for facilitation of development and for achieving satisfactory model-based control. LÄS MER