Sökning: "Observational Method"

Visar resultat 16 - 20 av 161 avhandlingar innehållade orden Observational Method.

  1. 16. Aerosol-cloud interaction from an observational and modeling perspective

    Författare :Anders Engström; Annica Ekman; Heiner Körnich; Philip Stier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : Clouds may respond strongly to changes in the atmospheric aerosol population, and the response of clouds to an increased global aerosol burden could to some extent mask the warming caused by enhanced greenhouse gas concentrations. However, estimates of the impact of aerosols on cloud properties are associated with large uncertainties, both because of difficulties representing the aerosol-cloud interaction within models, and because of problems of unequivocally isolating the effect of aerosols on cloud properties in observational data. LÄS MER

  3. 17. Method developments for the attributable fraction in causal inference

    Författare :Elisabeth Dahlqwist; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : In public health and policy making, understanding the overall impact of an intervention is of essential importance. A way to quantify the disease burden due to some risk factor is by the attributable fraction (AF). LÄS MER

  4. 18. Spatial positioning : method development for spatial analysis of interaction in buildings

    Författare :Henrik Markhede; Jesper Steen; John Peponis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Architecture; Arkitektur;

    Sammanfattning : In offices, knowledge sharing largely depends on everyday face-to-face interaction patterns. These interaction patterns may depend on how employees move through the office space. This thesis explores how these spatial relations influence individual choices with respect to employee movements or routes. LÄS MER

  5. 19. Design and analysis of response selective samples in observational studies

    Författare :Maria Grünewald; Ola Hössjer; Keith Humphreys; Marie Reilly; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ascertainment; missing data; outcome dependent sampling; response selective samples; sequential design; stochastic EM algorithm; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : Outcome dependent sampling may increase efficiency in observational studies. It is however not always obvious how to sample efficiently, and how to analyze the resulting data without introducing bias. LÄS MER

  7. 20. Sensitivity Analysis of Untestable Assumptions in Causal Inference

    Författare :Mathias Lundin; Xavier de Luna; Maria Karlsson; Sune Karlsson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Observational studies; semiparametric regression; unconfoundedness; Causal inference; Statistics; Statistik; Statistics; statistik;

    Sammanfattning : This thesis contributes to the research field of causal inference, where the effect of a treatment on an outcome is of interest is concerned. Many such effects cannot be estimated through randomised experiments. For example, the effect of higher education on future income needs to be estimated using observational data. LÄS MER