Sökning: "random covariance matrix"
Visar resultat 6 - 10 av 25 avhandlingar innehållade orden random covariance matrix.
6. Contributions to High–Dimensional Analysis under Kolmogorov Condition
Sammanfattning : This thesis is about high–dimensional problems considered under the so{called Kolmogorov condition. Hence, we consider research questions related to random matrices with p rows (corresponding to the parameters) and n columns (corresponding to the sample size), where p > n, assuming that the ratio converges when the number of parameters and the sample size increase. LÄS MER
7. Data driven modeling in the presence of time series structure: : Improved bounds and effective algorithms
Sammanfattning : This thesis consists of five appended papers devoted to modeling tasks where the desired models are learned from data sets with an underlying time series structure. We develop a statistical methodology for providing efficient estimators and analyzing their non-asymptotic behavior. LÄS MER
8. Modeling Realized Covariance of Asset Returns
Sammanfattning : In this thesis, which consists of two papers, we consider the modeling of positive definitive symmetric matrices, in particular covariance matrices of financial asset returns. The return covariance matrix describes the magnitude in which prices of financial assets tend to change over time, and how price changes between different assets are related. LÄS MER
9. Scalable Bayesian spatial analysis with Gaussian Markov random fields
Sammanfattning : Accurate statistical analysis of spatial data is important in many applications. Failing to properly account for spatial autocorrelation may often lead to false conclusions. LÄS MER
10. Studies in Estimation of Patterned Covariance Matrices
Sammanfattning : Many testing, estimation and confidence interval procedures discussed in the multivariate statistical literature are based on the assumption that the observation vectors are independent and normally distributed. The main reason for this is that often sets of multivariate observations are, at least approximately, normally distributed. LÄS MER
