Sökning: "Measurement theory"

Visar resultat 21 - 25 av 387 avhandlingar innehållade orden Measurement theory.

  1. 21. Adolescent mental health : time trends and validity of self-report measures

    Författare :Ida Blomqvist; Eva Henje; Inga Dennhag; Anne Hammarström; Lotte Haverman; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Adolescent; classical test theory; computer adaptive testing; cross-sectional; differential item functioning; graded response model; item banks; item response theory; measurement invariance; mental health; Patient-Reported Outcomes Measurement Information System; Reynolds Adolescent Depression Scale second edition; self-report measures; time trends; barn- och ungdomspsykiatri; Child and Youth Psychiatry;

    Sammanfattning : Background: Studies of time trends of adolescent self-reported mental health suggest an increase of mental health symptoms globally. Unfortunately, several studies within the field have methodological problems, such as short time-period between measurements and different mental health measures over time. LÄS MER

  3. 22. An Intelligent Multi Sensor System for a Human Activities Space---Aspects of Quality Measurement and Sensor Arrangement

    Författare :Jiandan Chen; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 3D Reconstruction; Depth Measurement; Depth Reconstruction; Dither; Human Factor; Image Quality; Iso-disparity Surfaces; Multi-Sensor System; Quality Measurement; Sensor Arrangement; Surveillance; Tracking; Uncertainty;

    Sammanfattning : In our society with its aging population, the design and implementation of a highperformance distributed multi-sensor and information system for autonomous physical services become more and more important. In line with this, this thesis proposes an Intelligent Multi-Sensor System, IMSS, that surveys a human activities space to detect and identify a target for a specific service. LÄS MER

  4. 23. Multivariate Aspects of Phylogenetic Comparative Methods

    Författare :Krzysztof Bartoszek; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; General Linear Model; Ornstein-Uhlenbeck process; Multivariate phylogenetic comparative method; Evolutionary model; Adaptation; Optimality; Measurement error; Regression; Adaptation; Major-axis regression; Reduced major-axis regression; Structural equation; Allometry; Phylogenetic inertia; Allometry;

    Sammanfattning : his thesis concerns multivariate phylogenetic comparative methods. We investigate two aspects of them. The first is the bias caused by measurement error in regression studies of comparative data. We calculate the formula for the bias and show how to correct for it. LÄS MER

  5. 24. On the Measurement of Model Fit for Sparse Categorical Data

    Författare :Katrin Kraus; Dag Sörbom; Ghazi Shukur; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; goodness-of-fit; sparseness; model fit; categorical data; fit statistic; sparse contingency table; Statistics; Statistik;

    Sammanfattning : This thesis consists of four papers that deal with several aspects of the measurement of model fit for categorical data. In all papers, special attention is paid to situations with sparse data. LÄS MER

  7. 25. Solid-State Nanopores for Sensing : From Theory to Applications

    Författare :Chenyu Wen; Shi-Li Zhang; Zhen Zhang; Ulrich F. Keyser; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; solid-state nanopore; ionic current; current blockage; effective transport length; noise; surface charge; translocation; biomolecule; electroosmotic flow; vortex; autogenic translocation; multiple nanopores; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Sammanfattning : Nanopore based sensing technology has been widely studied for a broad range of applications including DNA sequencing, protein profiling, metabolite molecules, and ions detection. The nanopore technology offers an unprecedented technological solution to meeting the demands of precision medicine on rapid, in-field, and low-cost biomolecule analysis. LÄS MER