Data Analysis Journal

Data Analysis Journal

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My Consulting Journey: $0 to $685K in 6 months - Issue 232
An honest story of the highs, lows, and hard lessons from running an analytics consultancy.
 • Olga Berezovsky
10 Must-Know Concepts Every Analyst Should Know - Issue 290
From academia to industry - the core analytical principles we rely on every day.
 • Olga Berezovsky
Refresher on Retention - Issue 236
How to measure and report retention: cohorted and blended
 • Olga Berezovsky
How To Pull Stories From Data and Make Them Actionable - Issue 251
Finding the Why: turning raw data into clear, actionable insights and stories
 • Olga Berezovsky
How to Create Decks That Don’t Suck - Issue 245
Or why we all hate PowerPoint - and how to make presentations that don’t make people hate you
 • Olga Berezovsky
Which Analyst Are You? - Issue 262
Data analyst career guide: an overview of roles, skills, and industry trends
 • Olga Berezovsky
Forecasting in Analytics: Choosing the Right Approach - Issue 249
How to predict revenue, user growth, and key business metrics using moving averages, regression, and ML
 • Olga Berezovsky
The Battle You’ll Always Lose: Documentation - Issue 234
How to create and maintain proper documentation in analytics.
 • Olga Berezovsky
How To Develop Analytical Intuition - Issue 254
Error-spotting and how to cross-check metrics when the data won’t match.
 • Olga Berezovsky
Refresher on SQL for Data Analysis - Issue 238
SQL solutions for data analysis, ad hoc, and modeling.
 • Olga Berezovsky
From Analytics to Data Science: Building Forecasts - Issue 257
A step-by-step guide to ARIMA and Prophet to forecast events, transactions, and customer growth.
 • Olga Berezovsky
How To Do a Root Cause Analysis - Issue 162
A framework for analyzing KPI decline and locating the root causes for unexpected user behavior change
 • Olga Berezovsky
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