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Visar resultat 1 - 5 av 35 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Statistical methods for register based studies with applications to stroke

   Författare :Anita Lindmark; Marie Eriksson; Xavier de Luna; Eva-Lotta Glader; Saskia le Cessie; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Registers; quality of care; socioeconomic status; hospital performance; stroke; mediation; sensitivity analysis; truncation; censoring; Statistics; statistik;

   Sammanfattning : This thesis adds to the area of register based research, with a particular focus on health care quality and (in)equality. Contributions are made to the areas of hospital performance benchmarking, mediation analysis, and regression when the outcome variable is limited, with applications related to Riksstroke (the Swedish stroke register). LÄS MER

3. 2. Spatial sampling and prediction

   Författare :Lina Schelin; Sara Sjöstedt-de Luna; Silvelyn Zwanzig; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Auxiliary variables; Censoring; Inclusion probabilities; Kriging; Local pivotal method; Minimum detection limit; Prediction intervals; Representative sample; Spatial process; Spatial sampling; Semiparametric bootstrap; Mathematical Statistics; matematisk statistik;

   Sammanfattning : This thesis discusses two aspects of spatial statistics: sampling and prediction. In spatial statistics, we observe some phenomena in space. Space is typically of two or three dimensions, but can be of higher dimension. LÄS MER

4. 3. Estimation of wood fibre length distributions from censored mixture data

   Författare :Ingrid Svensson; Sara Sjöstedt - de Luna; Lennart Bondesson; Aila Särkkä; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; censoring; fibre length distribution; identifiability; increment core; length bias; mixture; stochastic EM algorithm; Mathematical statistics; Matematisk statistik;

   Sammanfattning : The motivating forestry background for this thesis is the need for fast, non-destructive, and cost-efficient methods to estimate fibre length distributions in standing trees in order to evaluate the effect of silvicultural methods and breeding programs on fibre length. The usage of increment cores is a commonly used non-destructive sampling method in forestry. LÄS MER

5. 4. Functional clustering methods and marital fertility modelling

   Författare :Per Arnqvist; Sara Sjöstedt de Luna; Leif Nilsson; Helle Sørensen; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; censoring; Coale-Trussell model; EM-algorithm; functional data analysis; functional clustering; marital fertility; normal approximation; Poisson process; varved lake sediments; warping; Mathematical Statistics; matematisk statistik;

   Sammanfattning : This thesis consists of two parts.The first part considers further development of a model used for marital fertility, the Coale-Trussell's fertility model, which is based on age-specific fertility rates. A new model is suggested using individual fertility data and a waiting time after pregnancies. LÄS MER

7. 5. Fatigue limit, inclusion and finite lives - a statistical point of view

   Författare :Sara Lorén; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; censoring; likelihood; profile predictive likelihood; staircase test; extreme value; likelihood;

   Sammanfattning : An important design property of steel is the fatigue limit, i.e. the load level where a specimen has infinite life. For the material it can also be defined an endurance limit, which is the stress level at which the specimen has a certain life. LÄS MER