Sökning: "random walks"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden random walks.

1. 1. Critical Scaling in Particle Systems and Random Graphs

   Författare :Vasilii Goriachkin; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dissipative force; particles collisions; random graphs; random walks; martingales; geometric random graphs; neural networks; critical scaling; diffusion approximation;

   Sammanfattning : The purpose of this thesis is to study the behavior of macro-systems through their micro-parameters. In particular, we are interested in finding critical scaling in various models.Paper I investigates the influence of discrete-time collisions on particle dynamics. LÄS MER

3. 2. Random Geometry and Reinforced Jump Processes

   Författare :Tuan-Minh Nguyen; Probability and Inference Theory Group; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; random polygons; products of random matrices; vertex-reinforced jump processes; pseudotrajectories; random walks in simplexes; Markov chains in a general state space;

   Sammanfattning : This thesis comprises three papers studying several mathematical models related to geometric Markov processes and random processes with reinforcements. The main goal of these works is to investigate the dynamics as well as the limiting behaviour of the models as time goes to infinity, the existence of invariant measures and limiting distributions, the speed of convergence and other interesting relevant properties. LÄS MER

4. 3. Studies in respondent-driven sampling : Directed networks, epidemics, and random walks

   Författare :Jens Malmros; Tom Britton; Fredrik Liljeros; Erik Volz; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematical Statistics; matematisk statistik;

   Sammanfattning : Respondent-driven sampling (RDS) is a link-tracing sampling methodology especially suitable for sampling hidden populations. A clever sampling mechanism and inferential procedures that facilitate asymptotically unbiased population estimates has contributed to the rising popularity of the method. LÄS MER

5. 4. On Directed Random Graphs and Greedy Walks on Point Processes

   Författare :Katja Gabrysch; Svante Janson; Takis Konstantopoulos; Thomas Mountford; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Directed random graphs; Tracy-Widom distribution; Poisson-weighted infinite tree; Greedy walk; Point processes;

   Sammanfattning : This thesis consists of an introduction and five papers, of which two contribute to the theory of directed random graphs and three to the theory of greedy walks on point processes.          We consider a directed random graph on a partially ordered vertex set, with an edge between any two comparable vertices present with probability p, independently of all other edges, and each edge is directed from the vertex with smaller label to the vertex with larger label. LÄS MER

7. 5. Cover Times, Sign-dependent Random Walks, and Maxima

   Författare :Anna Carlsund; KTH; []
   Nyckelord :;

   Sammanfattning : .... LÄS MER