The reliability of statistics is essential for official statistics. With administrative data more often used instead of survey data, non-sampling errors become important factors in the accuracy of...Show moreThe reliability of statistics is essential for official statistics. With administrative data more often used instead of survey data, non-sampling errors become important factors in the accuracy of statistics. For domain statistics, such as yearly turnover of enterprises, classification errors occur. This study aims to measure the effect of classification errors on domain statistics, more specially, bias and variance due to classification errors. In this study, a new method was developed that applies a Gaussian mixture model, estimated by the EM algorithm, in short referred to as the EM method. Further another method was introduced that combined the EM method with bootstrapping, referred to as the combined method. Among them, the EM method only estimates bias, and the combined method is able to estimate both bias and variance. Together with a previously used bootstrap method, the three methods were tested in a simulation study and in a case study. The bias and variance estimates from the three methods were compared with their corresponding true values in different settings. The results showed that the bias estimates from the EM and the combined method were closer to the true values compared to the bootstrap method; The combined method had closer outputs on variance estimation than the bootstrap method. The EM and the combined method were equally accurate in estimating the true bias. These results suggest that the EM and the combined method estimated the bias and variance more accurately than the bootstrap method. In practice, the combined method is recommended since both the bias and the variance can be estimated. In a situation with a very large data set, where the variance is usually small and the bias is of most concern, the EM method may be preferred.Show less
Een casusstudie naar het gebruik van de opbrengst van het waterbeheerprogramma 2016-2021, als inbreng voor het opstellen van het Waterbeheerprogramma 2022-2027 van Waterschap Rivierenland aan de...Show moreEen casusstudie naar het gebruik van de opbrengst van het waterbeheerprogramma 2016-2021, als inbreng voor het opstellen van het Waterbeheerprogramma 2022-2027 van Waterschap Rivierenland aan de hand van het Strategisch Planningsmodel van Bryson (2011).Show less
Authentication of a communication channel usually requires that the parties meet physically; but there is one solution if it is enough to confirm the geographical location of a party: quantum...Show moreAuthentication of a communication channel usually requires that the parties meet physically; but there is one solution if it is enough to confirm the geographical location of a party: quantum position verification (QPV). This is based on quantum mechanics, the no-cloning theorem, and special relativity, the invariance of the speed of light. We shown an extension of a QPV protocol where quantum information is communicated via the polarization state of single photons including the effects of photon loss and polarization noise, and explore it by numerical simulations. Moreover, we have designed and implemented the first steps of a QPV demonstration using optical fibers. We have been able to calibrate the setup for horizontal and vertical polarization states where a visibility of approximately 0.85 has been measured.Show less
The focus of this study is to assess sexual dimorphism of non-metric and metric characteristics of the mandible of a Dutch post Medieval rural population from the Middenbeemster polder in the...Show moreThe focus of this study is to assess sexual dimorphism of non-metric and metric characteristics of the mandible of a Dutch post Medieval rural population from the Middenbeemster polder in the province of Noord Holland in the Netherlands. The mandible is not seen as a reliable feature for sex estimation in research on Dutch Medieval populations based on non-metric traits. Studies on populations around the world show that the mandible is a reliable tool for estimating sex, provided that metric measurements of the mandible are used. This study focuses on the re-evaluation of the mandible as a reliable tool for sex estimation by studying both non-metric and metric sexual dimorphism of the mandible in a Dutch population. The development of a technique that reliably estimates mandibular sex in Dutch medieval populations would be a great contribution to the field of bioarchaeology. Sex estimation is paramount for the reconstruction of demographic structures of past societies. In this thesis sexual dimorphism based on both non-metric and metric is assessed. 90 samples from the Middenbeemster with known sex are used for measurement and observations. This sample consists of 40 females and 50 males. The non-metric scores are compared to known sex to assess reliability. The metric measurements are analysed using binary logistic regression and tree modelling to assess if the specific measurements are reliable in estimating sex of an unknown individual. The overall accuracy of the non-metric sex estimation is very low and therefore not reliable for further use. The metric measurements have a higher reliability rate, especially the bigonial breadth and the mean of the maximum ramus height. With the use of these two measurements a cross validated classification accuracy of 80.2 percent can be achieved. In conclusion, after re-evaluating the mandible it appears that the mandible can be used with high accuracy in sex estimation in the Dutch population of Middenbeemster and maybe in other North Western European populations from the post Medieval time period, which has to be assessed by future research.Show less
As the basic unit of chromatin, the form in which DNA is tightly packed in the nucleus of eukaryotic cells, the nucleosome forms a physical barrier during transcription of the DNA. Understanding...Show moreAs the basic unit of chromatin, the form in which DNA is tightly packed in the nucleus of eukaryotic cells, the nucleosome forms a physical barrier during transcription of the DNA. Understanding the energetic landscape of the nucleosome during transcription extends our knowledge on how the nucleosome affects gene expression. An in vitro study of the energetic landscape of native nucleosomes has never been done. To facilitate such a study, techniques need to be developed to mechanically unzip native chromatin. In this research, we developed techniques on DNA unzipping using magnetic tweezers that are needed for the localization of nucleosomes in chromatin unzipping. We investigated long-lifetime DNA tethering to improve reproducibility and experimental practicality, which is vital for tethers containing nucleosomes. Techniques of force barrier localization during DNA unzipping were developed that could be used on nucleosomes. Two-state equilibrium statistical mechanics models for DNA unzipping and overstretching were developed that are extendable to include more states. These techniques aim to facilitate experiments on native nucleosomes that shine light on their fundamental role in epigenetics.Show less
