Browsing by Author "De Kock, Michiel B."

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    From chi^2 to Bayesian model comparison : the example of Levy-based fits to e+e- correlations
    (Proceedings of Science, 2012) De Kock, Michiel B.; Eggers, Hans C.; Csorgo, Tamas
    The usual χ2 method of fit quality assessment is a special case of the more general method of Bayesian model comparison which involves integrals of the likelihood and prior over all possible values of all parameters. We introduce new parametrisations based on systematic expansions around the stretched exponential or Fourier-transformed Lévy source distribution, and utilise the increased discriminating power of the Bayesian approach to evaluate the relative probability of these models to be true representations of a recently measured Bose-Einstein correlation data in e +e− annihilations at LEP.
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    Rapid deconvolution of low-resolution time-of-flight data using Bayesian inference
    (AIP Publishing LLC, 2019) Pieterse, Cornelius L.; De Kock, Michiel B.; Robertson, Wesley D.; Eggers, Hans C.; Miller, R. J. Dwayne
    The deconvolution of low-resolution time-of-flight data has numerous advantages, including the ability to extract additional information from the experimental data. We augment the well-known Lucy-Richardson deconvolution algorithm using various Bayesian prior distributions and show that a prior of second-differences of the signal outperforms the standard Lucy-Richardson algorithm, accelerating the rate of convergence by more than a factor of four, while preserving the peak amplitude ratios of a similar fraction of the total peaks. A novel stopping criterion and boosting mechanism are implemented to ensure that these methods converge to a similar final entropy and local minima are avoided. Improvement by a factor of two in mass resolution allows more accurate quantification of the spectra. The general method is demonstrated in this paper through the deconvolution of fragmentation peaks of the 2,5-dihydroxybenzoic acid matrix and the benzyltriphenylphosphonium thermometer ion, following femtosecond ultraviolet laser desorption.