Rafael Karcz
Portfolio

Intro

Welcome to my corner of the digital world.
I’m Rafael Karcz. I'm a Data & Business Analyst and Definite Optimist who believes that small shifts can create deep impact.

With a background in International Management & Business Economics and a certification as a Microsoft Power BI Data Analyst (Coursera), I specialize in turning data into decisions and building workflows that save time, reduce friction, and open space for growth.

My toolkit spans Power BI (DAX, star-schema modeling, deployment pipelines, RLS, governance), SQL (CTEs, window functions, optimization), and Python (automation scripts, data wrangling, web scraping), along with Git, Bash, and REST APIs. In the travel tech industry, I’ve applied these skills to optimize CRM systems for 800+ users, support database stability, and contribute to automation projects that keep complex operations running smoothly.

But beyond analytics, I’m an adventurer at heart. From the bustling streets of Central America to the serene landscapes of New Zealand and the cultural depth of Japan, travel has shaped how I see the world: adaptable, curious, and open to diverse perspectives.

At the intersection of data, technology, and global experience, I carry a simple ethos:

Let the good travel.

If this resonates with you, let's connect — over data, collaboration, or even just a good coffee.

Curriculum Vitae

• Generic CV (English)
• Generic CV (German)

Projects

Featured work that reflects how I think: clear models, clean visuals, and practical automation.

Power BI

Sales & Operations Tracker

Self-initiated report combining sales, targets, and operational KPIs. Parameterized measures, dynamic slicers, and role-appropriate views to keep teams aligned.

• GitHub repo

Capstone Report

Interactive business report from the certification program. Star-schema modeling, curated DAX (KPIs, time intelligence), and layout focused on decision speed.

• GitHub repo

Python

Correlation Analysis

Explores relationships across film/movie metrics using Pandas and Matplotlib. Emphasis on wrangling, visualization, and clear takeaways from correlation patterns.

• GitHub repo

Article Scraper

Scrapes a target site, filters by article type, and saves clean .txt files in page-based folders. Shows HTML parsing (BeautifulSoup), robust file handling, and filename sanitation for reproducible outputs.

• GitHub repo

Learning Tracker

CLI tool that tracks courses and progress over time. Clean OOP structure, persistence, and a simple UX for quick, repeatable updates.

• GitHub repo

Investor Calculator

Database-driven CLI for storing company metrics and calculating key indicators. Built with SQLAlchemy; shows CRUD, schema design, and reproducible analysis.

• GitHub repo

SQL

Expense Tracker

MySQL expense tracker: normalized schema and SQL (joins/CTEs/windows) for income vs. expense, monthly trends, rolling totals, and overspend alerts.

• GitHub repo

COVID-19 Analysis

CTEs and window functions to explore cases, deaths, and vaccination trends. Focus on data cleaning, exploration, and actionable insights.

• GitHub repo

Strategy & Analytics

Ad-Block Challenge

Data-driven strategy to address revenue loss from ad-blocking. Combined user research, metric design, and scenario modeling to recommend relevance-first formats with clear impact paths.

• Google doc

Kudos & Merits

Welcome to my Kudos & Merits page. Here you’ll find a few words from people I’ve worked with and the credentials I’ve earned along the way. Each note of praise is a snapshot of collaboration, and each merit is a marker of progress. Together, they reflect my aim to create clarity, cut friction, and let the good travel.

Kudos

• English: Kudos from the Datamics GmbH
• German: Kudos von der Datamics GmbH

While this section is still short and sparse, I am sure it will grow as I go on with life.

Merits

Professional Certifications

• Microsoft Power BI Data Analyst Professional Certificate (Coursera)
• Jetbrains certified: Introduction to Python
• Data Analytics Bootcamp (Alex the Analyst)
• Business Analytics Specialization (The Wharton School)
• Jetbrains certified: Introduction to SQL
• Jetbrains certified: Introduction to Command Line and Unix Shell
• Inferential Statistics (The University of Amsterdam)
• Learning How to Learn (Coursera)
• Basic Statistics (The University of Amsterdam)
• Qualitative Research Methods (The University of Amsterdam)
• Quantitative Methods (The University of Amsterdam)

Academic Diplomas

• Academic Transcript (Tokyo International University)
• Certificate (Tokyo International University)
• Certificate of English as Medium of Instruction (Tokyo International University)
• Certificate of Enrollment Period (Tokyo International University)
• Academic Transcript (Macromedia University Munich)
• Course Report (EF)
• Certificate (EF – Japanese)

Currently Pursuing

• Python Developer Course - Jetbrains/Hyperskill
• AWS Fundamentals Specialization - Coursera

Contact

Email

rafael.karcz [at] gmail.com

Phone

+81 80 5803 8623

Address

Tokyo, Japan

Social

• LinkedIn
• GitHub

Whether it is data, collaboration, or just a good coffee, feel free to reach out.

Elements

i = 0;

while (!deck.isInOrder()) {
    print 'Iteration ' + i;
    deck.shuffle();
    i++;
}

print 'It took ' + i + ' iterations to sort the deck.';