Projects
Determining sample requirements for modeling and reporting (stability of) school value-added estimates: sample size, inter-school student mobility and sample heterogeneity KU Leuven
Within the context of school accountability systems, many countries use value added (VA)-estimates as indicators of the educational quality or effectiveness of their schools. A fundamental issue in this field is the (in)stability of VA estimates across time, i.e., the extent to which school effects persist over successive cohorts of students. VA-estimates are less stable, i.e., less reliable, especially for primary schools and for schools ...
Easier, better, faster, stronger: developing statistical methods for conducting sample size planning in intensive longitudinal designs KU Leuven
Easier, better, faster, stronger: developing statistical methods for conducting sample size planning in intensive longitudinal designs KU Leuven
The use of intensive longitudinal studies has skyrocketed in recent years as it allows researchers to investigate within-person psychological dynamic processes. However, intensive longitudinal research lacks an overarching framework to inform researchers on how to optimally design a study. Specifically, a key question that researchers need to address is how to select the sample size to be able to answer research questions and derive reliable ...
Topics in discrete choice experiments: Screening, framing, and sample size selection KU Leuven
Discrete Choice Experiments are now used in almost all fields to study choice behavior. The methods to design and analyze those experiments have been investigated and improved over the years, allowing researchers to yield more accurate and reliable information without putting a larger burden on the respondents. Despite these advancements, the literature on choice modeling recognizes that several areas are still open for improvement. In this ...
Reduction in sample size by order constraints Ghent University
This project aims to study the relationship between the number of order restrictions imposed on the parameters of a statistical model and the possible reduction in sample size. The goals are to (1) construct power tables for order constrained tests, and (2) providing user-friendly software so that testing order constrained hypotheses is easily accessible to applied users.
Small sample solutions for structural equation modeling. Ghent University
Small samples (N<150) are a problem for structural equation modeling (SEM), both for estimation of model parameters, as for model-based inference. This project will develop solutions to stabilize the model estimation part, and to improve the model-based inference if the sample size is small. This will
allow researchers with sample sizes to use SEM.
The influence of lake mixing, light availability and trophic status on species sorting and size structure of planktonic diatom communities along a climate gradient in Southern Chile Ghent University
We will quantify the realized niches and size-structure of planktonic diatoms in Chilean lakes as a function of mixing regime and light and nutrient availability. We will combine diatom analyses of environmental samples with experiments. This will allow us to assess the effect of climate change on the taxonomic turnover and size structure of planktonic diatoms in sediment cores.
Solid phase storage of analytes originating from liquid matrixes. Ghent University
Liquid matrixes are standard sample collection materials for drugs at the workplace. At this stage, the majority of liquid samples (urine, serum, saliva,…) that are collected on site, are transported as such to analytical laboratories and stored in their collection form. Transportation of bulky, heavy samples from the collection site to the analytical laboratory is expensive however and inappropriate transportation conditions can lead to ...
Geophysical surveys and interpretation geotechnical soil investigation outside Zeebrugge harbor sediment and landfill sites S1 under Flemish bays Ghent University
in a first dee mission is twofold and includes! carrying out seismic measurements as a function of the detailed mapping of the lithology and stratigraphy of the Quaternary, Neogeen and the top of the paleogene at the height of the outer side of the port of Zeebrugge. In this warden specific techniques and methods employed that result in an image of the layer structure, as far as possible, oak in the zones with natural gas, previously ...