Dietrich Stoyan (born November 26, 1940, Berlin) is a German mathematician and statistician who made contributions to queueing theory, stochastic geometry, and spatial statistics.
Stoyan studied mathematics at Technical University Dresden; applied research at Deutsches Brennstoffinstitut Freiberg, 1967 PhD, 1975 Habilitation. Since 1976 at TU Bergakademie Freiberg, Rektor of that university in 1991—1997. He became famous by his statistical research of the diffusion of euro coins in Germany and Europe after the introduction of the euro in 2002. In 2024, he criticized together with Sung Nok Chiu a wrong proof of the hypothesis that the origin of the COVID-19 pandemic was a market in Wuhan which was published in the journal Science. [1]
Dietrich Stoyan is an honorary doctor of the Technical University of Dresden (2000) and the University of Jyväskylä (2004). He was a member of the Academy of Sciences of the GDR (1990), which disappeared in 1991. At present he is a member of the Academia Europaea (since 1992), the Berlin-Brandenburg Academy of Sciences (since 2000) and the German Academy of Sciences Leopoldina (since 2002). He is also a Fellow of the Institute for Mathematical Statistics (since 1997). In 2018 he published his autobiography In two times. [2]
Qualitative theory, in particular inequalities, for queueing systems and related stochastic models. The books
report on the results. The work goes back to 1969 when he discovered the monotonicity of the GI/G/1 waiting times with respect to the convex order.
Stereological formulae, applications for marked point processes, development of stochastic models. Successful joint work with Joseph Mecke led to the first exact proof of the fundamental stereological formulae.
A book entitled "Stochastic Geometry and its Applications" reports on these results. Its 3rd edition is the key reference for applied stochastic geometry. [3]
Statistical methods for point processes, random sets and many other random geometrical structures such as fibre processes. Results can be found in the 2013 book on stochastic geometry and in the book, Fractals, Random Shapes and Point Fields by D. and H. Stoyan. (J. Wiley and Sons, Chichester, 1994).
A particular strength of Stoyan is second-order methods.
He is also the main author of the book Statistical analysis and modelling of spatial point patterns. [4] It treats the statistics of point patterns with methods of point process theory.
Stoyan is very active in demonstrating non-mathematicians and non-statisticians the potential of statistical and stochastic geometrical methods. He published many papers in journals of physics, materials science, forestry, and geology. One topic of particular interest was random packings of hard spheres. He co-organized together with Klaus Mecke conferences where physicists, geometers and statisticians met. See the books
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Ole Eiler Barndorff-Nielsen was a Danish statistician who has contributed to many areas of statistical science.
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In probability and statistics, a point process operation or point process transformation is a type of mathematical operation performed on a random object known as a point process, which are often used as mathematical models of phenomena that can be represented as points randomly located in space. These operations can be purely random, deterministic or both, and are used to construct new point processes, which can be then also used as mathematical models. The operations may include removing or thinning points from a point process, combining or superimposing multiple point processes into one point process or transforming the underlying space of the point process into another space. Point process operations and the resulting point processes are used in the theory of point processes and related fields such as stochastic geometry and spatial statistics.
In probability and statistics, a moment measure is a mathematical quantity, function or, more precisely, measure that is defined in relation to mathematical objects known as point processes, which are types of stochastic processes often used as mathematical models of physical phenomena representable as randomly positioned points in time, space or both. Moment measures generalize the idea of (raw) moments of random variables, hence arise often in the study of point processes and related fields.
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Jesper Møller is a Danish mathematician.