Search for dissertations about: "exponential distribution"

Showing result 1 - 5 of 71 swedish dissertations containing the words exponential distribution.

  1. 1. Properties and tests for some classes of life distributions

    Author : Bengt Klefsjö; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Life distribution; survival function; exponential distribution; IFR; IFRA; NBUE; DMRL; HNBUE; shock model; total time on test transform; testing of exponentiality;

    Abstract : A life distribution and its survival function F = 1 - F with finitemean y = /q F(x)dx are said to be HNBUE (HNWUE) if F(x)dx < (>)U exp(-t/y) for t > 0. The major part of this thesis deals with the classof HNBUE (HNWUE) life distributions. READ MORE

  2. 2. Testing and estimation in labour supply and duration models

    Author : Niklas Karlsson; Umeå University; []
    Keywords : SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; labour supply; quantity constraint; perceived tax scale; duration; specification test; distribution;

    Abstract : Estimation and testing in labour supply and unemployment duration models are studied. In the first two papers estimation techniques designed to account for quantity constraints and perceived tax scales are developed, while the remaining three papers focus on specification tests. READ MORE

  3. 3. Analysis of Perfluoroalkyl Acids in Swedish Biota : Temporal trends, tissue distribution and toxicity

    Author : Katrin Holmström; Urs Berger; Gregg Tomy; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; PFOS; PFAS; pollutant; Baltic guillemot; peregrine falcon; Monoporeia affinis; time trend; toxicity; Environmental chemistry; Miljökemi; Persistent organic compounds; Persistenta organiska föreningar; Applied Environmental Science; tillämpad miljövetenskap;

    Abstract : Perfluorinated alkyl acids (PFAS) are ubiquitous environmental contaminants. They are found in high concentrations in top predators worldwide, with perfluorooctane sulfonate (PFOS) as the predominant compound. READ MORE

  4. 4. Modeling the covariance matrix of financial asset returns

    Author : Gustav Alfelt; Joanna Tyrcha; Taras Bodnar; Vasyl Golosnoy; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Realized covariance; Autoregressive time-series; Goodness-of-fit test; Matrix singularity; Portfolio theory; Wishart distribution; Matrix-variate gamma distribution; Parameter estimation; High-dimensional data; Moore-Penrose inverse; matematisk statistik; Mathematical Statistics;

    Abstract : The covariance matrix of asset returns, which describes the fluctuation of asset prices, plays a crucial role in understanding and predicting financial markets and economic systems. In recent years, the concept of realized covariance measures has become a popular way to accurately estimate return covariance matrices using high-frequency data. READ MORE

  5. 5. Stability and Exponential Convergence for the Boltzmann Equation

    Author : Bernt Wennberg; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Keywords : ;

    Abstract : This thesis is devoted to the long-time behaviour of the nonlinear Boltzmann equation for a class of molecular interactions, including inverse power laws for hard potentials. It has been known for some time now, that under natural conditions on the initial data, the space homogeneous Boltzmann equation possesses a unique, global solution, and that this solution tends strongly to the equilibrium distribution as time tends to infinity. READ MORE