Welcome to Data Analysis Journal

Go behind the scenes of genuine data analysis and data storytelling.

Data Analysis Journal is a weekly newsletter and advice column about data analysis, data science, and product analytics. Trusted by tens of thousands of analysts and data scientists around the world, it aims to bridge the gap between academia and the industry.

I’m Olga, an analyst-in-residence and data scientist. Born in Ukraine and based in San Francisco. I led a product analytics team at MyFitnessPal and previously worked at Change.org, Microsoft, First Republic Bank, and quite a few big and small startups that paid me in knowledge and cookies. 

My superpower lies in my focus on user engagement and behavior analytics by identifying product personas, building feature impact and growth matrices, and proving relationships between user engagement and revenue. Revenue growth is elusive without strong product usage and active engagement. That’s why I closely watch the DAU/MAU ratio, user retention, and CPO state of mind.

In my free time, I usually stare coldly into foreboding time series charts until they permanently burn into my eyes. When I am not doing that, I write about all the data things people make me do at work with the hope of expanding and advancing analytics.

With over a decade of trial and error, I share what good or bad analysis practice is, what framework to use to solve a challenge, what interviewers look for, how to hire the best talent, and how to structure and grow data analytics teams.

Here is the story of how this newsletter started and grew.

You can find me on Twitter and LinkedIn.

When you subscribe to Data Analysis Journal, you will receive:

  • SQL and Python solutions, interview questions, and guidance.

  • Deep dives and analytical case studies.

  • Data analysis project examples and walkthroughs.

  • Examples of successful (and not really) A/B tests, rollout procedures, and their analyses.

  • Insights from data analytics and data science industry experts.

  • My frameworks and playbooks for analysis, reporting, metric calculations, test evaluations, and forecasts. 

What readers say

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Posting schedule

  • Paid subscribers will receive one newsletter a week and get full access to the website along with my mentorship and support.

  • Free subscribers will receive one newsletter per month.

Proceeds from subscriptions are donated to Ukrainian Children's Aid and Relief Effort charity.

If your company would like to purchase a group subscription at a discounted rate, click here:

Get a group subscription

I am giving a 50% discount to all active students and recent graduates → click here. You can also email me at olga@berezovsky.me with your university/school name to receive a discount.

If you are looking for a job, and can’t afford a paying subscription, please email me at olga@berezovsky.me, and I will set you up!

I love what I do, and my mission is to show you just how exciting and impactful data analysis can be.

Subscribe to Data Analysis Journal

Where product, data science, and analytics intersect. Trusted by tens of thousands of data scientists around the world


Medieval Analyst who loves data  and analysis and writes about fun things people make her do at work