Jeffrey O.

Hi, my name is Jeffrey, and I am an expert R and SQL developer with a proven track record of delivering exceptional results through comprehensive data analysis, building packages, and statistical computing. My expertise in R covers a diverse range of libraries. I'm skilled at using tools like dplyr and ggplot2 for efficient data manipulation and creating engaging visualizations. I love making sense out of messy data by cleaning, manipulating, and validating it with tools such as base R, stringr, forcats, tidyr, dplyr, and janitor. I harness the power of machine learning to intricately analyze data, using libraries such as caret, glmnet, keras, xgboost, randomForest, e1071, and rpart to extract valuable insights relevant to unique projects. I am also somewhat of an addict to data visualization! I make dashboards with RShiny, captivating maps, and charts that convey stories or communicate insights very well. I find immense joy in creating custom packages in R that cater to the specific needs of businesses or individual projects. I take pride in assembling code into reusable components, streamlining workflows for optimal efficiency. Developing R-based products is particularly satisfying for me, knowing they make a significant impact on the success of companies and projects alike. I am also an expert in SQL, specializing in PostgreSQL and BigQuery. Additionally, I am a proficient Python programmer with a specific focus on data analysis and web scraping. SKILLS - Data Analysis: Descriptive Statistics, Exploratory Data Analysis, Data Visualization, and Factor Analysis (Exploratory and Confirmatory) - Data Science: ANOVA Models, Generalized Linear Models (i.e., logistic, poison, ordinal, etc.), Path Analysis and Structural Equation Modeling, t-test, Hierarchical/Multilevel Regression Models, Supervised Machine Learning Algorithms (Linear Regression, Logistic Regression, Decision Trees, etc.), Unsupervised Machine Learning Algorithms - Web Development: HTML, CSS, Javascript, React, GitHub - Digital Marketing: Search Engine Optimization & Search Engine Marketing, Google Tag Manager, Google Ads, Google Analytics, and Facebook Business Manager - IT Support: Endpoint Manager, Teamviewer, CA DSM Explorer, Linux, Wireshark, Active Directory, Microsoft Office Author of 2 R Packages: - kickR - wikiscrapeR TECH STACK Data Analysis and Data Science: - Python - R - Stata - RStudio - Pandas, NumPy - Matplotlib, Seaborn, Plotly - Scikit-learn - Git Digital Marketing: - Google Analytics, Google Tag Manager - Google Ads, Facebook Business Manager - Marketing automation tools (HubSpot) - A/B testing tools IT Support: - Endpoint Manager - TeamViewer - Linux - Active Directory - Microsoft Office Suite Geography and GIS: - ArcGIS, QGIS - GeoDa LANGUAGES - Native Speaker: English - Professional Proficiency: German, French - Beginner to Intermediate: Danish, Portuguese & Norwegian PROJECTS Data Analysis & Data Science: - An Analysis of the World's BRT Systems, an Analysis with R. * Exploratory Data Analysis on Bus Rapid Transport Systems Across the World - What Your Heart Rate is Telling You: An Analysis with R. * Used multiple logistic regression to handle the confounding effects of age and gender. - A Visual History of Nobel Prize Winners: An Analysis with R. - An Analysis of International Debt Statistics with SQL - Kidney Stones and the Simpson's Paradox, an analysis with R. * Used multiple logistic regression to help the doctors determine if there is a difference between the two treatments. - Predicting Movie Similarity using Movie Summaries: an analysis with Python * Using hierarchical clustering to recommend movies based on similarity - New York Uber Rides: An Analysis with R. * Insights from publicly available data on Uber trips in New York City - COVID-19: From an epidemic to a global pandemic, an analysis with R. - Dr. Semmelweis and the Discovery of Handwashing: An Analysis with R. * An analysis of the data backing one of the crucial discoveries in modern medicine: handwashing - Which Debts Are Worth a Bank's Effort? An analysis with Python * Used regression discontinuity to determine which debts are worth collecting by a bank. - Most Important Characters in Game of Thrones: An analysis with Python * Used network analysis to determine the most important characters in the critically acclaimed show: Game of Thrones. P.S: The North Remembers. - Heart Disease and Potential Risk Factors: An Analysis with R. * Ran statistical tests and regression models using the Cleveland heart disease dataset to assess one particular factor: the maximum heart rate one can achieve during exercise and how it is associated with a higher likelihood of getting heart disease. - The GitHub History of Scala Language: An Analysis with Python * Reviewing the development of Scala. - Recreating Jon Snow's Ghost Map, an analysis with Python * Recreating Jon Snow's Ghost Map During London's Cholera Outbreak in 1854