R is my swiss knife for medium and complex data problems.
2000 – 2004 I learned R in order to implement my PhD Thesis (available on Amazon.com) on a credit scoring model using neural networks, random forests and other techniques.
In 2007 I joined www.datacamp.com a NY based training company to refresh and extend my R skills in approx 360 hours training – the main part during lockdowns in COV-19 crisis 2020. I started with an hands on comprehensive tour by completing all courses in the career tracks.
Solid foundation (~200 hours training)
Data Scientist 
Data Analyst 
R Programmer 
Machine Learning Scientist
+
Practical applications (~48 hours training)
Marketing Analytics 
Network Analytics 
Textmining
Visualizations (~50 hours training)
Data Visualization 
Interactive Datavisualization 
Shiny & Flex Dashboards
Deep Dives Methods (~62 hours training)
Time Series Analysis 
Supervised Learning 
Unsupervised Learning