Dénes Tóth, Ph.D., Developer in Nyíregyháza, Hungary
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Dénes Tóth, Ph.D.

Verified Expert  in Engineering

Data Scientist and Developer

Nyíregyháza, Hungary
Toptal Member Since
December 3, 2020

Denes holds a Ph.D. in cognitive science and an MSc in business administration and statistics: his native language is data. Since 2015, he has been delivering data analytic services in various industry sectors. He is a co-organizer of the Hungarian R meetup and contributes to various open-source R packages. Formerly, Denes worked as a research lab leader at the Brain Imaging Centre of HAS, where he excelled at answering challenging questions by first gaining a deep understanding of the problem.


Reporting, Statistical Modeling, Science, Experimental Research, SQL...
Brain Imaging Centre, Research Centre for Natural Sciences...
Reporting, Science, Experimental Research, Statistics, Machine Learning...




Preferred Environment

Statistical Modeling, Web Dashboards, Machine Learning, Data Visualization, Data Mining, Docker, Azure, SQL, RStudio Shiny, R

The most amazing...

...thing that I've worked on was a vehicle routing algorithm and SaaS software which is used by a large wholesale company to deliver goods to ~6,000 clients.

Work Experience

Founder | Data Scientist

2013 - PRESENT
  • Developed, as lead developer, a cloud-based analytic dashboard in an Australian edutech project targeting automatized ETL, real-time analysis, ML-based prediction, visualization, and report generation (Radii.org/prolearning).
  • Translated business needs to functional specifications and developed the algorithm of a (SaaS) vehicle routing software that serves the logistics (~2,000 shops/day) of a large Hungarian wholesale company.
  • Optimized the logistics network (position of depots, assignment of shops to depots, visiting days) of a large Hungarian wholesale company by developing custom algorithms, using spatial statistics, and creating interactive visualizations and reports.
  • Created a detailed concept of a type of deduplication software for a large Hungarian society; this included data mining of a mostly undocumented database, data cleansing, algorithm benchmarking, creating a business glossary and DB documentation.
  • Created data visualizations for a financial MBA course organized by the University of Lugano.
  • Published and distributed a computerized dyslexia test (3DM-H) which is widely used by professional organizations in Hungary to provide a reliable diagnosis of dyslexia in primary grades (see also below).
  • Held R courses for business clients and research institutes.
Technologies: Reporting, Statistical Modeling, Science, Experimental Research, SQL, Web Dashboards, Training, Training & Training Content Development, Teaching, Predictive Modeling, Spatial Analysis, Logistics, Data Processing, Database Schema Design, MongoDB, Cloud Computing, Scientific Data Analysis, Data Visualization, Business Administration, Machine Learning, Statistics, Data Analysis, RStudio Shiny, R, Java, JavaScript, Consulting, Data Mining, Docker, Azure, Data Science

Research Fellow | Lab Leader

2005 - 2017
Brain Imaging Centre, Research Centre for Natural Sciences, Hungarian Academy of Sciences
  • Designed cognitive-behavioral and EEG experiments, analyzed data, developed R toolbox for ERP analyses, mentored Ph.D. and undergrad students, wrote research articles receiving over 1,000 citations (Researchgate.net/profile/Denes_Toth2).
  • Wrote a (successful) research grant application for the project "Cues and Rules: Neurocognitive Examination of Acoustic and Visual Processing of Words;" designed the series of experiments, the budget, timeline, and so on.
  • Participated in the EU research project "NEURODYS—Dyslexia genes and neurobiological pathways" including 15 research groups from nine countries; contributed to highly cited research articles.
  • Participated in an EU research project "PROREAD (Socrates)—Explaining Low Literacy Levels by Profiling Poor Readers and their Support" including 5 research groups from five countries; contributed to highly cited research articles.
  • Authored the Hungarian adaptation of the 3DM fully computerized dyslexia test; adapted subtests, implemented stimulus presentation code, organized large-scale data collection, performed psychometric data analysis, wrote manuals, and more.
  • Contributed to research articles as a statistical consultant of other research groups.
  • Held statistics and R courses at research universities.
Technologies: Reporting, Science, Experimental Research, Statistics, Machine Learning, Data Analysis, Data Visualization, Data Mining, Data Science, Cognitive Psychology, Research, Statistical Modeling, EEG, Scientific Data Analysis, Cognitive Science, R

Analytic Dashboard (Edutech)

I worked as the lead developer of a full-stack SaaS analytic dashboard application for an Australian organization (RADII ProLearning, Radii.org/prolearning). The project includes extensive data integration and preprocessing steps, automated real-time statistical and predictive modeling, interactive visualization, and reporting.

The project grew out of a smaller-scale task, including the integration and cleansing of educational data collected from primary schools in Australia. The task was very challenging due to the total lack of documentation and extreme variability of data sources and data quality. Fun fact: I was first hired to build structural equation models on the data—it became evident very quickly that this would not be possible without the appropriate input.

Now the system is a SaaS web application hosted in Azure with lots of capabilities not covered by any other contemporary solutions on the market: the school user can run complex analyses and create informative reports intuitively without any knowledge about statistics. The software is in beta and shows great potential, also supported by the Microsoft for Startups program.

Learn Fast: Vehicle Routing

A consultancy working with a large multi-depot wholesale company delivering goods to ~6,000 clients per week approached me for advice on optimizing the logistics network of their client. Specifically, the client wanted to know how many drivers they need for a highly reliable and still cost-efficient delivery network.

At that time, I knew almost nothing about vehicle routing problems. However, in one month, I reviewed the literature, chose an open-source Java library, and despite being totally new to Java, tweaked the code to meet the need of the actual problem, wrote the R scripts which preprocessed the data, and ran the required simulations.

In the end, the client was so satisfied they asked me to advise them on further optimization possibilities, e.g., improve the depot-assignments or visiting days of their customers.

Later, the client decided to develop a highly customized vehicle routing software that can handle their specific demands. I developed and tuned the algorithm of the software and helped the client identify the functional requirements. The software was implemented in Scala, to which I contributed high-level pseudocode and several Java prototypes. The system is in production since 2017.


R, SQL, JavaScript, CSS, Java


RStudio Shiny


Data Science

Industry Expertise



Data Mining, Data Visualization, Machine Learning, Statistical Modeling, Experimental Research, Science, Cognitive Psychology, Psychology, Cognitive Science, Experimental Design, Statistics, Data Analysis, Modeling, Data Processing, Consulting, Scientific Data Analysis, Predictive Modeling, Training, EEG, Research, Reporting, Training & Training Content Development, Web Dashboards, Cloud Computing, Database Schema Design, Logistics, Spatial Analysis, Vehicle Routing, Business Administration


Visual Studio Code (VS Code), Azure, Docker, Linux


Data Integration, Azure SQL Databases, MongoDB

2005 - 2009

Ph.D. in Cognitive Science

Eötvös Loránd University - Budapest, Hungary

2000 - 2005

Master's Degree in Psychology

Eötvös Loránd University - Budapest, Hungary

2004 - 2004

Erasmus Exchange in Cognitive Psychology

University of Konstanz - Konstanz, Germany

1998 - 2003

Master's Degree in Business Administration, Statistics

University of Economics (Corvinus) - Budapest, Hungary

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