Sökning: "data size"

Visar resultat 16 - 20 av 2243 avhandlingar innehållade orden data size.

  1. 16. Testing for Periodicity and Trend in Long-Memory Processes

    Författare :Abdullah Almasri; Statistiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Statistics; temperature data.; sunspots data; wind speed data; varve data; Siegel’s test; Fisher’s test; periodogram; Fractional difference process; Discrete wavelet transform; operations research; programming; actuarial mathematics; Statistik; operationsanalys; programmering; aktuariematematik; Wavelets; Statistik;

    Sammanfattning : This thesis presents methods of testing the periodicity and trend for the time series, which exhibit dependence over long periods of time. Many such processes can be modeled by a class of models called fractionally differenced processes. LÄS MER

  2. 17. Ensembles of Semantic Spaces : On Combining Models of Distributional Semantics with Applications in Healthcare

    Författare :Aron Henriksson; Hercules Dalianis; Martin Duneld; Nigel Collier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; natural language processing; machine learning; distributional semantics; ensemble learning; semantic space ensembles; medical informatics; electronic health records; Computer and Systems Sciences; data- och systemvetenskap;

    Sammanfattning : Distributional semantics allows models of linguistic meaning to be derived from observations of language use in large amounts of text. By modeling the meaning of words in semantic (vector) space on the basis of co-occurrence information, distributional semantics permits a quantitative interpretation of (relative) word meaning in an unsupervised setting, i. LÄS MER

  3. 18. Some properties of measures of disagreement and disorder in paired ordinal data

    Författare :Hans Högberg; Elisabeth Svensson; Sture Holm; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; agreement; augmented ranks; categorical data; disorder; jackknife; paired ordinal data; rating scales; sample size; sampling distribution; simulation; U-statistics; variance; SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; Statistics; Statistik; Statistics; Statistik;

    Sammanfattning : The measures studied in this thesis were a measure of disorder, D, and a measure of the individual part of the disagreement, the measure of relative rank variance, RV, proposed by Svensson in 1993. The measure of disorder is a useful measure of order consistency in paired assessments of scales with a different number of possible values. LÄS MER

  4. 19. Why and how brain size evolves : Sociality, predation and allometry

    Författare :Wouter van der Bijl; Niclas Kolm; Joah Madden; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; brain size; brain size evolution; encephalization; predation; predator inspection; sociality; animal contest; constraint; etologi; Ethology;

    Sammanfattning : The evolution of the vertebrate brain has remained a topic of intense interest from biologists over many decades. Evolutionary biologists have seen it as an intriguing example of how the size and structure of a trait evolves across large phylogenies and under body size constraints, with both large shifts in deep evolutionary time and continuous smaller scale adaptation. LÄS MER

  5. 20. Aspects of analysis of small-sample right censored data using generalized Wilcoxon rank tests

    Författare :Marie-Louise Öhman; Hans Nyquist; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Censored generalized Wilcoxon rank test statistics; Variance estimation; Jackknifing; Influence function; Gross error sensitivity; Break-Down point; Sensitivity curve; Location parameter estimation; Product-Limit estimator and Monte-Carlo Simulation; Statistics; computer and systems science; Statistik; data- och systemvetenskap; Statistics; statistik;

    Sammanfattning : The estimated bias and variance of commonly applied and jackknife variance estimators and observed significance level and power of standardised generalized Wilcoxon linear rank sum test statistics and tests, respectively, of Gehan and Prentice are compared in a Monte Carlo simulation study. The variance estimators are the permutational-, the conditional permutational- and the jackknife variance estimators of the test statistic of Gehan, and the asymptotic- and the jackknife variance estimators of the test statistic of Prentice. LÄS MER