Sökning: "Missing values"
Visar resultat 1 - 5 av 82 avhandlingar innehållade orden Missing values.
1. Interpretable machine learning models for predicting with missing values
Sammanfattning : Machine learning models are often used in situations where model inputs are missing either during training or at the time of prediction. If missing values are not handled appropriately, they can lead to increased bias or to models that are not applicable in practice without imputing the values of the unobserved variables. LÄS MER
2. Statistical modeling in international large-scale assessments
Sammanfattning : This thesis contributes to the area of research based on large-scale educational assessments, focusing on the application of multilevel models. The role of sampling weights, plausible values (response variable imputed multiple times) and imputation methods are demonstrated by simulations and applications to TIMSS (Trends in International Mathematics and Science Study) and PISA (Programme for International Student Assessment) data. LÄS MER
3. Rainfall-Runoff Modelling Using Artificial Neural Networks (ANNs)
Sammanfattning : Over the last decades or so, artificial neural networks (ANNs) have become one of the most promising tools for modelling hydrological processes such as rainfall-runoff processes. In most studies, ANNs have been demonstrated to show superior result compared to the traditional modelling approaches. LÄS MER
4. Classification and Computational Methods in Gene Expression Data Analysis
Sammanfattning : The technology of cDNA microarrays has given us the possibility to monitor the state of cells by measuring the activity of thousands of genes simultaneously. This high-throughput techniqe has in cancer research allowed exploratory studies of molecular mechanisms behind for example metastasis and response to therapy. LÄS MER
5. Solidaritet och utbildning för hållbar utveckling : En studie av förväntningar på och förutsättningar för miljömoraliskt lärande i den svenska gymnasieskolan
Sammanfattning : The comprehensive ambition of the present thesis was to acquire knowledge about expectations on and preconditions for environmental moral learning within the education for sustainable development (ESD) in the Swedish upper secondary school. The expectations on ESD were explored by examining the description of “sustainable development” in the curriculum, and the prerequisites were examined by analysing environmental attitudes, commitments, and actions of 18-year-old students. LÄS MER