Joanna Ronchi | Data Science Portfolio

Portfolio focus

Projects Built for Technical Review and Business Interpretation.

This portfolio emphasizes reproducible analysis, model validation, data storytelling, and stakeholder-ready recommendations—the kind of work hiring teams can quickly connect to real-world analytics roles.

Best first impression

Featured Projects

Strongest examples of business relevance, technical skill, storytelling, and decision support.

Predictive analytics

Nevada Appellate Case Timing Analysis

Python • Multiple Linear Regression • Model Validation • Data Visualization

Analyzed 2,729 Nevada appellate cases to identify case characteristics that influence disposition timing. Built and validated a predictive model explaining 71% of timing variation, then translated findings into clear visuals and recommendations for non-technical stakeholders.

Business value: Supports transparency, workload planning, early delay identification, and evidence-based decision-making.

GitHub repo Video presentation

Dashboard

Customer Churn Tableau Dashboard

Tableau • Customer Analytics • Segmentation • Retention Strategy

Explored churn patterns across customer segments and service characteristics, helping organizations identify why customers leave and where retention efforts can have the most impact.

Business value: Helps prioritize targeted retention strategies and improve long-term customer value.

GitHub repo Video walkthrough

NoSQL analytics

HealthFit MongoDB Aggregation Project

MongoDB • Aggregation Pipelines • Python • Node.js

Used MongoDB aggregation pipelines to generate actionable health and business insights, with baseline and optimized queries exported in both JavaScript and Python formats.

Business value: Demonstrates efficient document-database analytics for extracting actionable insights from semi-structured data. Demonstrates document-database querying, optimization, and analytics delivery from semi-structured data.

GitHub repo Video walkthrough

Modeling and analysis

Machine learning & Statistical Modeling

Regression, classification, clustering, hypothesis testing, and forecasting projects with model evaluation and business interpretation.

Regression

Housing Price Prediction Model

Python • EDA • Feature Selection • Model Validation

Built a multiple linear regression model to predict residential property values using structural, neighborhood, and economic characteristics. The final model explained approximately 61% of housing price variation.

Business value: Helps estimate residential property values, identify the factors that drive housing prices, and support data-driven real estate decisions.

GitHub repo Video walkthrough

Classification

Luxury Home Classification

Python • Logistic Regression • Feature Engineering

Developed a logistic regression model to classify luxury homes, achieving approximately 73% testing accuracy while identifying important property characteristics for market segmentation.

Business value: Helps identify high-value properties for pricing strategy, market segmentation, and real estate decision-making.

GitHub Video

PCA

Housing Price PCA Regression

Python • PCA • Regression • Model Interpretation

Applied dimensionality reduction and regression modeling to estimate residential property values while demonstrating interpretable predictive analytics for valuation and pricing strategy.

GitHub Video

Hypothesis testing

Health Insurance Cost Analysis

Python • Welch's t-test • Chi-square • ANOVA

Analyzed insurance cost drivers with exploratory analysis, descriptive statistics, visualizations, hypothesis testing, effect-size interpretation, and business recommendations.

GitHub Video

Random forest

Churn Prediction Model

Python • Machine Learning • Classification

Developed a random forest model for churn prediction, demonstrating supervised learning and customer-risk modeling for retention-focused analytics.

GitHub Video

Clustering

Customer Segmentation with K-Means

Python • K-Means • Segmentation

Used unsupervised learning to group customers into meaningful segments, supporting more focused marketing, service design, and customer strategy.

GitHub Video

Forecasting

Telecommunications Revenue Forecasting

Python • ARIMA • Time-Series Modeling

Built a time-series forecasting workflow to model telecommunications revenue trends and support forward-looking planning decisions.

GitHub

Applied data work

Data Engineering, Cleaning & Deployment

Projects that show practical work employers care about: data quality, reproducible workflows, database design, and deployment readiness.

Data cleaning

Employee Turnover Preprocessing Pipeline

Python • Pandas • Data Quality • HR Analytics

Built a preprocessing pipeline for 10,000+ employee records, including profiling, duplicate detection, missing-value imputation, categorical standardization, outlier analysis, validation, and feature engineering.

GitHub Video

Database design

EcoMart Database Design

Relational Design • SQL • Data Modeling

Designed a database solution for EcoMart, demonstrating schema planning, business-rule translation, and data organization for operational analytics.

Video

API deployment

Flight Delay API Deployment

API • Docker • Deployment

Demonstrated deployment concepts for a flight-delay analytics API using Docker, showing how model outputs can be packaged for practical use.

Video

About

About Joanna

Data scientist with a background in IT management, accounting, and analytics, focused on transforming data into practical recommendations for business and public-sector decision-making.

What I Bring

Strong analytical judgment, business context, and the ability to explain technical findings clearly to non-technical stakeholders.

Project Strengths

Reproducible notebooks, clean documentation, visual storytelling, model validation, and direct links to code and presentation walkthroughs.

Business Analytics Financial Analysis Data Storytelling Model Evaluation Dashboard Design Stakeholder Communication