Efthymios K.
Thessaloniki, Greece
95%
Job Success
Top Rated
Data Analyst /PhD Statistician / Shiny App / Machine Learning / R
$25.00/hr
With a strong academic foundation and extensive professional experience in business intelligence, data visualization, and statistical modeling, I am confident in my ability to contribute effectively to any organization.
After earning my degree in Finance, where I gained a solid grounding in Finance, Statistics, Macroeconomics, and Marketing, I pursued a Master's in Business Informatics. Most recently, I completed an MSc in Complex Systems and Networks, where I extensively used R to graphically represent statistical models and complex networks. These academic pursuits have honed my analytical and technical skills, while fostering a deep appreciation for the interplay between Computer Science and Economic Sciences.
Currently, I am advancing my expertise through a PhD program, focusing on the application of machine learning and network science techniques in financial and economic systems. My research involves the development of predictive models and causal inference frameworks, using large-scale data analysis to address complex, real-world challenges in financial markets and organizational behavior. This experience has deepened my proficiency in quantitative methodologies, reinforced my ability to handle interdisciplinary projects, and enhanced my problem-solving approach when working with intricate datasets.
In my professional experience as a Business Intelligence Analyst, I specialize in transforming complex datasets into actionable insights. My work involves leveraging tools such as R/Shiny, Tableau, Qlik Sense, and Microsoft Power BI to deliver data-driven solutions that align with business objectives. Additionally, I have collaborated with various firms on freelance projects, further refining my expertise in data visualization and statistical modeling.
As an author for R-exercises, I have published tutorials and exercises on R packages like shiny, ggplot2, ggvis, and Rmarkdown, as well as machine learning methodologies. Through these contributions, I have demonstrated my ability to break down complex concepts into accessible and practical solutions, benefiting both professionals and learners in the field.
My diverse academic and professional background has equipped me with a unique perspective, blending precision, creativity, and technical expertise. I am passionate about solving complex problems, uncovering actionable insights, and driving data-informed decision-making.
I am excited about the possibility of contributing to impactful projects and would be delighted to discuss how my background aligns with organizational needs.
Attached you can find URLs of some of my Shiny projects. There are only parts of them that I had clients' permission to deploy and use as a portfolio.
Work history
Work history
Statistical Analysis for Patient Trend Comparison
Feb 12, 2025
-
Apr 6, 2025
"I hired him for a retrospective analysis involving complex biometric data - he was able to generate helpful images and synthesize the data into meaningful insight."
Private earnings
Data visualization expert
Mar 11, 2025
-
Mar 26, 2025
Private earnings
Data Analysis (statistical) on Largest CH and GER Companies Over 20 Years
Mar 14, 2025
-
Mar 18, 2025
"Efthymios was really helpful in providing valuable insights and working fast, even during the night which helped me a lot. When I didn't understand something he took the time to…
Private earnings
R Data Visualization: Column Chart Creation
Dec 14, 2024
-
Mar 17, 2025
"I highly recommend Efthymios. He solved a coding problem in R very quickly and successfully."
Private earnings
Statistician needed for dental resident research project
Jan 31, 2024
-
Mar 11, 2025
Private earnings
Create R data visualisations
Mar 1, 2025
-
Mar 2, 2025
Private earnings
Data Regression for Football Transfer Research
Feb 23, 2025
-
Feb 25, 2025
Private earnings
setting up R Studio and preparing data
Jun 14, 2024
-
Feb 24, 2025
"Makis, I enjoyed working with you. Once my projects pick back up I will be back in touch."
Private earnings
SEM Analysis Using R or Mplus
Jan 24, 2025
-
Feb 22, 2025
"Efthymios is great, I highly reccomend working with him."
Private earnings
Employ statistical techniques to scrutinize data and produce actionable business insights
Jan 29, 2025
-
Feb 21, 2025
"We needed to explain everything multiple times."
Freelancer's response
"Being a top rated upwork freelancer for over 7 years and to more than 260 jobs I have proven my quality. I was about to contact with specific member of…
Private earnings
Statistician for E-Commerce Experiments & Forecasting (Long-Term, Purpose-Driven Work)
Mar 31, 2025
-
Present
Job in progress
Private earnings
Econometrics & Time Series
Mar 18, 2025
-
Present
Job in progress
Private earnings
Statistical analysis with R
Mar 17, 2025
-
Present
Job in progress
Private earnings
Conduct polynomial regression LLM with additional specs, 4-5 var on the y axis, 1 x-axis var
Mar 2, 2025
-
Present
Job in progress
Private earnings
Data Analysis of Text Marketing Effectiveness & Customer Opt-Outs
Feb 26, 2025
-
Present
Job in progress
Private earnings
R Automation Consult
Feb 14, 2025
-
Present
Job in progress
Private earnings
Statistical Data Analysis Expert Needed
Jan 14, 2025
-
Present
Job in progress
Private earnings
Research interviews with ML Engineers
Jan 9, 2025
-
Present
Job in progress
Private earnings
Expert Needed for NLP Regression Model Development for the CONSTRUCTION sector
Dec 10, 2024
-
Present
Job in progress
Private earnings
R Shiny Developer
Apr 9, 2024
-
Present
Job in progress
Private earnings
Efthymios K. has more jobs. Create an account to review them
Skills
Skills
- Data Visualization
- R
- ggplot2
- Machine Learning
- Data Analysis
- Data Science
- Statistics
- R Shiny
- Markdown
- Statistical Analysis
- Data Mining
- Deep Learning
- Python