janus-web-ab-testing 0.1.1

Janus, an A/B Test Framework.

Janus

Janus is an A/B Test Engine to be used in a variety use cases, especially to measure conversion, ticket and ARPU difference between variants, i.e, typical metrics for tests in marketplaces. The engine name is an analogy to Janus, the god of changes and transitions.

This library came as an ideia of separate the statistical calculations in A/B Tests from other code that is typically used to manage tests and execute queries over the company's database, and hence usually carry proprietary code and even business logic, which should not be open sourced. There was the bud to build this library and get it open sourced.

Checkout the streamlit app from this repo.

Installation

Janus is distributed in pypi. You can install it by using:

pip install janus-web-ab-testing

You can now run a quick example of a A/B test:

from janus.variant import Variant
from janus.experiment import WebsiteExperiment

variant_A = Variant(
    name="A",
    impressions=1000, 
    conversions=100, 
    revenue=10000
)
variant_B = Variant(
    name="B",
    impressions=1000, 
    conversions=120, 
    revenue=9000
)
variants = [variant_A, variant_B]

experiment = WebsiteExperiment(variants, baseline_variant="A")
experiment.run()
experiment.print_reports()

See more in the quickstart notebook.

The Janus Website

My plan is to build a website to showcase the Janus library and to provide a simple interface to run A/B tests. However, only the library is almost ready, and the next steps would be:

• build a backend with FastAPI using the library
• build a frontend (JavaScript maybe)
• deploy the website

References

• What is A/B Testing
• VWO paper about bayesian A/B testing
• Agile A/B testing with Bayesian Statistics and Python
• Understanding Bayesian A/B testing (using baseball statistics)
• It’s time to re-think A/B testing
• Conjugate Priors
• Curso de Teste A/B Bayesiano do Lazy Programmer
• Binomial Distributions
• Bayes theorem
• The quick proof of Bayes Theorem