Dr. Maroussia Nikiforova Slavtchova-Bojkova
|
- Professional Experience
- Post-doc Specializations and Visiting Positions
- Teaching activities
- Professional and Software Skills
- Knowledge of foreign languages
- Participation in international conferences
- List of Selected Publications
- Recent major accomplishments
- Reviewing and refereeing work
- Membership in Professional Societies
Professional Experience
- 2004 - Present: Associate Professor, Faculty of Mathematics and Informatics, Department of Operational Research, Probability and Statistics, Sofia University.
- 2001 - 2003: Adjunct Associate Professor, Faculty of Mathematics and Informatics, Department of Operational Research, Probability and Statistics, Faculty of Mathematics and Informatics, Sofia University.
- 1990 - 2000: Adjunct Assistant Professor, Department of Operational Research, Probability and Statistics, Faculty of Mathematics and Informatics, Sofia University.
- 2001 - Present: Senior Research Associate at the Department of Probability and Statistics, Institute of Mathematics and Informatics, Bulgarian Academy of Sciences.
- 1989 - 2000: Junior Researcher at the Department of Probability and Statistics, Institute of Mathematics and Informatics, Bulgarian Academy of Sciences.
Post-doc Specializations and Visiting Positions
- University of Extremadura, Badajoz, Spain. Branching processes in epidemiological context. Scientist in charge: Prof. Dr M. Gonzales 19/09 - 30/10/2007.
- Westfälishe Wilhelms-Universität Münster, Münster, Germany. Theoretical investigations of branching processes with two types of immigration – Central limit theorem and Law of large numbers. Scientist in charge: Prof. Dr Gerold Alsmeyer 01/10 – 30/12/2003.
- Westfälishe Wilhelms-Universität Münster, Münster, Germany. Preparing proposal for DFG joint research project on the limit problems for branching processes treated by renewal approach. Scientist in charge: Prof. Dr Gerold Alsmeyer 01/10 – 31/10/2002.
- University of Extremadura, Badajoz, Spain. Statistical Inferences for a special class of branching processes with immigration – non-parametric estimates and simulations. Scientist in charge: Prof. Dr M. Molina 01/09-30/09/2002.
- Vrije Universiteit Brussel, Brussel, Belgium. The purpose of the research work was to treat some real world problems related to population and repopulation experiments by use of branching processes with immigration. Tutor: Prof. F. Thomas Bruss, 3 months, 1996, Grant from Flemish Office for Scientific, Technical and Cultural Affairs, Belgium.
Teaching Activities
Lectures at the Faculty of Mathematics and Informatics and the Faculty of Biology of Sofia University, at the University of Mining and Geology and at the New Bulgarian University (Informatics Department) for undergraduate, graduate students and MSc degree students.
(I) Courses:
Probability and Statistics – basic and advanced;
Stochastic Processes – BSc and MSc degree;
Branching Processes – MSc degree;
Decision making theory (Bayesian approach) – MSc degree;
Probability and Statistics for Engineers;
Probability and Statistics for Biologists;
(II) Supervision of three M.Sc. students
(III) Leader of the M.Sc. Programme
Probability and Statistics at the Department of Probability, Operational Research and Statistics of the Faculty of Mathematics and Informatics of Sofia University.
Professional and Software Skills
Deep knowledge and experience in developing mathematical models for branching
stochastic systems with different types of migration
Knowledge in numerical computation and simulation methods for branching
processes
Knowledge in MATLAB and MAPLE packages.
Knowledge of Foreign Languages
Fluent in English and very good in Russian and good in French and Deutsch.
Participation in International Conferences
- 2007: Symposium on Stochastic Modelling in Population Dynamics, CIRM, Luminy, France
- 2006: Second International Congress on Mathematics, MICOM-2006, Cyprus
- 2006: XII-th International Conference on Probability and Statistics, Sozopol, Bulgaria
- 2005: Symposium on Branching Processes, Goteborg, Sweden
- 2004: XI-th International Conference on Probability and Statistics, Sozopol, Bulgaria
- 2003: First International Conference on Mathematics and Informatics for Industry, MII 2003, Thessaloniki, Greece,
- 2003: X-th International Conference on Probability and Statistics, Sozopol, Bulgaria
- 2002: Seminar on Stability, Varna, Bulgaria
- 2001: Second International Conference on Deterministic and Stochastic Modelling of Biointeraction, DESTOBIO'2000, West Lafayette, Indiana, USA
- 2000: Workshop on Biostatistics and Bioinformatics, Goteborg, Sweden
- 1998: Alcala First International Conference on Mathematical Ecology, Alcala de Henares (Madrid), Spain
- 1997: First International Conference on Deterministic and Stochastic Modelling of Biointeraction, Sofia, Bulgaria
- 1995: Athen's Conf. on Appl. Probab. and Time Ser. Anal., Greece
- 1993: First World Congress on Branching Processes, Varna, Bulgaria
- 1991: 7-th European Meeting of Young Statisticians, Oberwolfach, Germany
List of Selected Publications
Papers in Refereed Journals
- M. Gonzalez, R. Martinez, M. Slavtchova-Bojkova (2008): Stochastic monotonicity and continuity properties of the extinction time of Bellman-Harris branching processes: an application to epidemic modelling. Submitted in Adv. Appl. Prob.
- M. Slavtchova-Bojkova (2007) :From regeneration to escape the extinction in population experiments, Mathematica Balkanica. New Series Vol. 21, Fasc. 3-4, 289-300.
- R. Martinez, M. Slavtchova-Bojkova (2005): Comparison between Numerical and Simulation Method for Age-dependent Branching Models with Immigration, Pliska, (Studia Mathematica Bulgarica), 17, 147-155.
- G. Alsmeyer, M. Slavtchova-Bojkova (2005): Limit Theorems for Subcritical Age-dependent Branching Processes with Two Types of Immigration. Stochastic Models, 21(1), 133-147.
- M. Slavtchova-Bojkova, P. Becker-Kern, K. Mitov, (2004): Total Progeny in a Subcritical Branching Processes with State-dependent Immigration. Pliska, (Studia Mathematica Bulgarica), 16, 229-245.
- M. Slavtchova-Bojkova, N. M. Yanev (2000) Limit Theorems for Age-Dependent Branching Processes with Emigration. Comptes Rendus de l'Academie Bulgare des Sciences, 54, No 1.
- M. Slavtchova-Bojkova (2000): Computation of Waiting Time to Successful Experiment Using Age-dependent Branching Model. Ecological Modelling, 133, 125-131.
- F. T. Bruss, M. Slavtchova-Bojkova (1999): On Waiting Times to Populate an Environment and a question of Statistical Inference. Journal of Applied Probability, 36, 261-267.
- M. Slavtchova-Bojkova, N. M. Yanev (1994): Non-critical Branching Processes with Two Types of State-dependent Immigration, Comptes Rendus de l'Academie Bulgare des Sciences, 47, 13-16.
- M. Slavtchova-Bojkova (1991): Limit Theorems for Multitype Bellman-Harris Branching Processes with State-dependent Immigration. Serdica, (Bulg. Math. Publ.), 17, 144-156.
- M. Slavtchova-Bojkova, N. M. Yanev (1991): Non-critical Bellman-Harris Branching Processes with State-dependent Immigration. Serdica (Bulg. Math. Publ.), 17, 67-79.
- M. Slavtchova-Bojkova, N. M. Yanev (1990): Convergence in Distribution of Supercritical Bellman-Harris Branching Processes with State-dependent Immigration. Math.Balk. New ser, 4, 35-42.
- M. Slavtchova-Bojkova, N. M. Yanev (1988): Limit Theorems for Bellman-Harris Branching Processes with State-dependent Immigration. Comptes Rendus de l'Academie Bulgare des Sciences, 41, 27-33.
Papers in Conference Proceedings
- M. Slavtchova-Bojkova (2007): Education in Stochastics/Statistics – A Compulsory Part from the European Culture (Invited talk). Proceedings of the Thirty Sixth Spring Conference, Bulgaria, 102-108.
- M. Slavtchova-Bojkova (2003): A Stochastic Policy in purifying wasted industrial water using branching model, Proc. of the First International Conference on Mathematics and Informatics for Industry, 14-16 April, Thessaloniki, 335-342.
- M. Slavtchova-Bojkova (2002): On the Subcritical Age-dependent Branching Processes with Two Types of Immigration. Mathematics and Mathematical Education, Proceedings of the Thirty First Spring Conference, Borovets, Bulgaria, April 3-6, 187-191.
- M. Slavtchova-Bojkova, N. M. Yanev (2001): Subcritical Age-dependent Branching Processes with Emigration. Mathematics and Mathematical Education, Proceedings of the Thirtieth Spring Conference, Borovets, Bulgaria, April 8-11, 281-288.
- M. Slavtchova-Bojkova, N. M. Yanev (1997): Age-dependent branching processes with emigration and population dynamics. In: "Bulletin of the International Statistical Institute", 51-st Session, Contributed Papers, 557-558.
- M. Slavtchova-Bojkova (1996): Multi-type Age-dependent Branching Processes with State-dependent Immigration, Proceedings of the Athen's Conference on Applied Probability and Time Series Analysis, Ed. C.C. Heyde, Yu. V. Prohorov, R. Pyke, S. T. Rachev , Lecture Notes in Statistics, 114, 192-205, Springer Verlag, New York.
- M. Slavtchova-Bojkova, N. M. Yanev (1995): Age-dependent Branching Processes with State-dependent Immigration, Proceedings of the First World Congress on Branching Processes, Ed. C.C. Heyde, Lecture Notes in Statistics, 99, 77-89, Springer Verlag, New York.
- M. Slavtchova-Bojkova, N. M. Yanev (1987): Supercritical Branching Processes with Random Migration Stopped at Zero. Mathematics and Mathematical Education, Proceedings of the Sixteenth Spring Conference, Sunny Beach, Bulgaria, April 6-10, 538-544.
- M. Slavtchova-Bojkova, N. M. Yanev (1985): Limit Theorems for Supercritical Migration Branching Processes. Mathematics and Mathematical Education, Proceedings of the Fourteenth Spring Conference, Sunny Beach, Bulgaria, April 6-9, 590-593.
Books
- M. Slavtchova-Bojkova, Yanev, N. (2007) Branching Stochastic Processes, University press ”St. Kl. Ohridski”, Sofia, p. 107.
- M. Slavtchova-Bojkova (2002) Lecture Notes on Stochastic Processes, electronic version, Lecture Notes
Recent Major Accomplishments
- The ongoing research is concerned with age-dependent (Bellman-Harris) and Sevast'yanov's branching process, describing outbreaks of an infectious disease with incubation period. The main goal is to define the optimal proportion of susceptible individuals that has to be vaccinated in order to eliminate the disease. To this end the properties of the time to extinction of an infection, depending on the proportion of the immune individuals into the population are studied. From these results a vaccination policy based on the mean of the infection survival time is suggested. A simulation-based method to determine the optimal vaccination level is provided and as an illustration the data from outbreaks of avian influenza spreading in Vietnam at the end of 2006 has been analyzed.
- For the classical sub-critical age-dependent branching process the effect of the following two types of immigration patterns is studied. At a sequence of renewal epochs a random number of immigrants enters the population. Each subpopulation originating from one of these immigrants is refreshed by new immigrants and their offspring whenever it dies out, possibly after an additional delay period. This is the Bellman-Harris branching process with immigration at zero and immigration of renewal type. We prove strong law of large numbers and a central limit theorem for such processes. Similar conclusions are obtained for their discrete-time counterparts, called Galton-Watson processes with immigration at zero and immigration of renewal type. Our approach is based on the theory of regenerative processes, renewal theory and occupation measures and is quite different from those in earlier related works using analytic tools.
- New computational approach of treating the so-called “waiting time to the successful experiment” by branching processes is developed and gives rise to studying some proper characteristics of the processes on the condition of extinction.
- A code “SIMULATION SYSTEM for branching processes” is developed. No programming is necessary and all input data can be entered in user-friendly dialog boxes and graphics and (numerical) results can be easily and quickly obtained. The results can be stored in the Database table and may be analyzed easily. The code can be used for actual design, prediction and estimation of the parameters of different classes of branching processes. The SIMULATION SYSTEM is a simple professional tool to be used by biologists, engineers and decision-makers for simulation of the processes which could appear to be suitable for modelling of some real world problems related to population and re-population experiments, for example.
Reviewing and Refereeing Work
- Serdica, Bulgaricae Mathematicae Publicationes
- Stochastic Models, Communications in Statistics
- Zentralblatt fur Matematik
- Mathematical Reviews
Membership in Professional Societies
- Union of Bulgarian Mathematicians (since 1982)
- Bulgarian Statistical Society (since 1991)
- American Mathematical Society (since 1999)
- International Biometric Society (since 2008)