Evgeny Ivanov
e10v.me
Evgeny Ivanov
@e10v.me
Product director and former principal data scientist at a services marketplace
Pinned
I'm excited to introduce tea-tasting, a Python package for the statistical analysis of A/B tests 📈🎉

It features Student's t-test, Bootstrap, variance reduction using CUPED, power analysis, and other statistical methods.

1/5
I was thinking about the labor market congestion problem and came up with a solution that is often used in service marketplaces: pay to apply... 🧵
Prices as model weights: learning from dispersed data | Evgeny Ivanov
Market design to reduce labor market congestion.
e10v.me
October 24, 2025 at 6:33 AM
Another perspective on marshmallow test: market risk and diminishing marginal utility
October 10, 2025 at 7:31 AM
It’s astonishing that Google employs so many multilingual people yet designs products as if users speak only one language
August 31, 2025 at 7:01 AM
Some mentions of the quote "all models are wrong, but some are useful" should be followed by "the map is not the territory"
July 17, 2025 at 4:03 PM
We wanted flying cars, instead we got scooter riders honking at our backs and knocking us off our feet
July 2, 2025 at 7:49 AM
Pre-LLM era take-home assignments: focus on evaluating *answers*; LLM era: focus on evaluating *questions*.

"Here is the problem-solving case: […]. Use an LLM to solve it. Provide a summary of your conversation with the LLM, including the questions you asked and the final solution you obtained."
May 26, 2025 at 10:03 AM
Every relevant cost can ultimately be framed as an opportunity cost. So, in essence, opportunity cost is the only cost that matters.
May 13, 2025 at 1:01 PM
A ladder of questions in analysis:

1. Which question should we ask to address a decision or a problem?
2. Which model should we choose to answer the question?
3. Which assumptions must hold for the model to be valid, and do they hold?
... 🧵

#DecisionIntelligence #ModelThinking #Logic
May 12, 2025 at 12:35 PM
Reposted by Evgeny Ivanov
✨ Narwhals now supports PySpark

🎇 If you have a dataframe-agnostic function, you can pass in `pyspark.sql.DataFrame`

📈 Here's a demo, made with @marimo.io

🎁 BONUS feature: combine with SQLFrame, to generate SQL from @pola.rs syntax 🪄
May 9, 2025 at 1:41 PM
The version 1.0 of tea-tasting, a Python package for the statistical analysis of A/B tests, is now available. Notable improvements:

- Interactive user guides built with @marimo_io notebooks.
- Simulated experiments, including A/A tests.

#abtesting #statistics #datascience
May 5, 2025 at 1:42 PM
Wow, ChatGPT is really smart now 😜

But better check for yourself: github.com/e10v/tea-tas...

#abtesting #statistics #chatgpt #ai
March 31, 2025 at 9:14 AM
It's actually Cunningham's Law... Wait... Dammit!
Turnbull's law: "The best way to get the right answer on the Internet is not to ask a question; it's to post the wrong answer." I love it! :D
December 26, 2024 at 3:10 PM
The new version of tea-tasting, a Python package for the statistical analysis of A/B tests, is out.

Multiple hypothesis testing correction procedures to control false discovery rate (FDR) and family-wise error rate (FWER) have been added: tea-tasting.e10v.me/multiple-tes...
Multiple testing - tea-tasting: statistical analysis of A/B tests
A Python package for the statistical analysis of A/B tests
tea-tasting.e10v.me
December 2, 2024 at 1:00 PM
Wow, tea-tasting has just reached 200 stars ⭐📈

It's not thousands, but it still matters to me, given the narrow niche of statistical analysis of A/B tests in Python.

#abtesting #statisics
August 21, 2024 at 1:05 PM
Reposted by Evgeny Ivanov
I sorta dug around and slapped together a data people starter pack thing... I'm sure I missed a ton of people but it's hopefully better than nothing?

go.bsky.app/Dyzvuzp
August 13, 2024 at 7:32 PM
Curious fact about Ronald Fisher, the father of modern statistics and experimental design: he refused to believe that smoking tobacco caused lung cancer 🚬🤯

Fisher argued that correlation does not imply causation and even published a paper in Nature 🙈📊

1/2

#statisics #abtesting #causalinference
August 12, 2024 at 5:08 AM
August 2, 2024 at 6:15 AM
I'm excited to introduce tea-tasting, a Python package for the statistical analysis of A/B tests 📈🎉

It features Student's t-test, Bootstrap, variance reduction using CUPED, power analysis, and other statistical methods.

1/5
July 29, 2024 at 6:59 AM
I wrote two blog posts about ranking in a services marketplace, where customers can find professionals, and professionals can find customers.

In a two-sided matching platform, both sides have to choose each other for a deal to happen, and that makes the ranking problem harder and kind of unique 📈
January 15, 2024 at 1:41 PM
A/B testing on the "north star" metric is like gradient descent in reaching business optimum. And the significance level, alpha, is similar to the learning rate. 📈

The lower the alpha:

- The slower the convergence speed.
- The higher the risk of getting stuck in a local optimum.

1/3
December 26, 2023 at 7:44 AM
Started working on tea-tasting, a Python package for statistical analysis of A/B tests 📊

Check out my blog post where I explain the motivation for creating this package and the benefits of the RDD approach: e10v.me/tea-tasting-...
Readme Driven Development for an A/B testing analysis package | Evgeny Ivanov
tea-tasting: a Python package for statistical analysis of A/B tests. Adopting the Readme Driven Development approach.
e10v.me
December 11, 2023 at 11:00 AM
The first rule of the Dunning-Kruger club... Wait, weren't Dunning and Kruger the founding members? And is there a right way to measure self-overestimation, anyway? 📊📈

Discover more: e10v.me/debunking-du...
December 3, 2023 at 7:41 AM