Now showing items 44-63 of 130

    • Least squares estimates of regression functions with certain monotonicity and concavity/convexity restrictions 

      Dahlbom, Ulla (University of Gothenburg, 1998-06-01)
      In all regression problems the choice of model and estimation method is due to a priori information about the regression function. In some situations it is motivated to consider regression functions with specific non-parametric ...
    • Likelihood based methods for detection of turning points in business cycles - A comparative study 

      Andersson, Eva; Bock, David; Frisén, Marianne (University of Gothenburg, 2001-05-01)
      Methods for on-line monitoring of business cycles are compared with respect to the ability of early prediction of the next tum by an alarm for a tum in a leading index. Three likelihood-based methods for turning point ...
    • Longitudinal methods for analysis of early child health in Pakistan 

      Carlquist, Anders (University of Gothenburg, 1999-12-01)
      Statistical methods to analyse some aspects on early child health in Lahore, Pakistan are discussed. The aim of this thesis is to choose, examine and use statistical methods suitable to analyse different aspects of early ...
    • Longitudinal methods for analysis of the influence of breastfeeding on early child health in Pakistan 

      Carlquist, Anders; Erling, Valdemar; Frisén, Marianne (University of Gothenburg, 1999-11-01)
      Statistical methods for analysing aspects of early child health in Lahore, Pakistan are discussed. We construct generalised linear mixed models with a binomial response variable and both fixed and random explaining effects. ...
    • Maximum Likelihood Ratio based small-sample tests for random coefficients in linear regression 

      Petzold, Max; Jonsson, Robert (2003-08-01)
      Two small-sample tests for random coefficients in linear regression are derived from the Maximum Likelihood Ratio. The first test has previously been proposed for testing equality of fixed effects, but is here shown to be ...
    • Methods and evaluations for surveillance in industry, business, finance, and public health 

      Frisén, Marianne (University of Gothenburg, 2011-02-10)
      n overview on surveillance in different areas is given. Even though methods have been developed under different scientific cultures, the statistical concepts can be the same. When the statistical problems are the same, ...
    • Minimax Optimality of CUSUM for an Autoregressive Model 

      Knoth, Sven; Frisén, Marianne (University of Gothenburg, 2011-02-11)
      Different change point models for AR(1) processes are reviewed. For some models, the change is in the distribution conditional on earlier observations. For others the change is in the unconditional distribution. Some models ...
    • Modeling influenza incidence for the purpose of on-line monitoring 

      Andersson, Eva; Bock, David; Frisén, Marianne (2007-11-27)
      We describe and discuss statistical models of Swedish influenza data, with special focus on aspects which are important in on-line monitoring. Earlier suggested statistical models are reviewed and the possibility of using ...
    • Modelling the spatial patterns of influenza incidence in Sweden 

      Schiöler, Linus (University of Gothenburg, 2010)
      Information about the spatial spread of epidemics can be useful for many purposes. The spatial aspect of Swedish influenza data was analyzed with the main aim of finding patterns that could be useful for statistical ...
    • Monitoring a Freshwater Fishpopulation: Statistical Surveillance of Biodiversity 

      Pettersson, Magnus (University of Gothenburg, 1997-02-01)
      Statistical surveillance are methods for repeated analysis of stochastic processes, aiming to detect a change in the underlying distribution. Such methods are widely used for industrial, medical, economical and other ...
    • Monitoring macroeconomic volatility 

      Bock, David; van Dijk, Dick; Franses, Philip Hans (2004-01-01)
      In this paper we develop testing procedures for monitoring the stability of the variance of a time series. While the traditional approach to testing for structural change is retrospective, applying a single test to a ...
    • Monotonicity aspects on seasonal adjustment 

      Andersson, Eva (University of Gothenburg, 1999-03-01)
      Monotonicity is an important property in time series analysis. It is often of interest to know if the seasonal adjustment method used has altered the monotonicity or changed the time of turning points in a time series that ...
    • Monotonicity restrictions used in a system of early warnings applied to monthly economic data 

      Andersson, Eva (University of Gothenburg, 1999-04-01)
      When making political decisions, the ability to make correct predictions about the behaviour of the business cycle in the future is important. The ability to forecast business cycles determines the success of, for example, ...
    • MULTIPLE COMPARISON TESTS BASED ON THE BOOTSTRAP 

      Johnsson, Tommy (University of Gothenburg, 1986-01-01)
      A multiple test procedure for pairwise comparisons based on the bootstrap is presented. It is a stagewise test without any distributional assumptions. It is also very general according to the number and types of hypotheses ...
    • Multitype spatial point patterns with hierarchical interactions 

      Särkkä, Aila; Högmander, Harri (University of Gothenburg, 1998-01-01)
      Multitype spatial point patterns with hierarchical interactions are considered. Here hierarchical interaction means directionality: Points on a higher level of hierarchy affect the locations of points on the lower levels, ...
    • Multivariate based causality tests of twin deficits in the US 

      Hatemi-J, Abdulnasser; Shukur, Ghazi (University of Gothenburg, 2000-01-01)
      This paper provides an alternative methodology for testing the causality direction between Twin deficits in the US. Rao' s multivariate F -test combined with bootstraps simulation technique has appealing properties, ...
    • Multivariate outbreak detection 

      Schiöler, Linus; Frisén, Marianne (University of Gothenburg, 2010)
      On-line monitoring is needed to detect outbreaks of diseases like influenza. Surveillance is also needed for other kinds of outbreaks, in the sense of an increasing expected value after a constant period. Information on ...
    • NONPARAMETRIC REGRESSION WlITH SIMPLE CURVE CHARACTERISTICS 

      Holm, Sture; Frisen, Marianne (University of Gothenburg, 1985-04-01)
      The character of nonparametric statistical methods is that they are constructed for very general situations, without the specific narrow assumptions, which appear in the common parametric methods. Isotonic regression is a ...
    • On assessing multivariate normality 

      Holgersson, H.E.T. (University of Gothenburg, 2001-01-01)
      Statistical analysis frequently relies on the assumption of normality. Though normality may often be relaxed in view of inferences of for example population expectations, it can be crucial in other aspects such as diagnostic ...
    • On curve estimation under order restrictions 

      Pettersson, Kjell (2008-02-04)
      Robust regression is of interest in many problems where assumptions of a parametric function may be inadequate. In this thesis, we study regression problems where the assumptions concern only whether the curve is increasing ...