Say you're an Engineering Manager or a Product Manager, responsible for a business-critical search system on a website. Maybe e-commerce, maybe a marketplace, maybe something else. Search is sort of working, it doesn't crash, and it's fast, but there's a feeling that "search isn't great", and you've been …

As I've written about before, as a data scientist supporting a product or marketing team with A/B testing, the job is communication -- helping to translate between business requirements and what we can learn from statistics. I (and many, many others) have found that there is a lot of value in having a document, shared …

Recently I wrote a blog post that mentioned “Superiority” as a type of A/B test decision. In this post I want to talk about all five types of A/B test decision that I think are relevant. This is an adaptation and extension of a talk I gave last year at the Quant UX conference (it’s a great event, you should check it …

The "best practice", when evaluating the results of an online controlled experiment (A/B test), is to use classical statistical tests, proceeding with a change if (and only if) the result of the test includes a p value of less than 0.05. But, the American Statistical Association (ASA) said in a prominent 2016 …

A/B testing is a tool for supporting decision-making in business, and so in addition to getting the statistics right, it’s really important to communicate well with the non-statisticians who will have the final say on the go/no-go decision. Most A/B tests in practice are testing ratios, conversion rates of various …

I recently read Will Larson's excellent book Staff Engineer: Leadership beyond the management track. Larson covers the individual contributor (IC, not management) roles that software engineers fill after they are promoted past Senior Software Engineer, with titles like Staff and Principal ("Staff-plus"). In …

Suppose you’re a data scientist at an e-commerce web site that sells shoes, responsible for supporting A/B tests. Many A/B tests are easy, and there are a number of companies that sell tools that make the easy cases as simple as clicking a few buttons and looking at pretty graphs. But A/B tests can get statistically …

Just a quick post here to note a few professional accomplishments:

1. I just added a new publication to my vita -- a peer-reviewed conference proceeedings article about abstractions for building repeated, related versions of similar predictive models. Check out some longer thoughts on Medium, or read the full article. …

This post was originally published on Medium

I recently attended two small conferences — the ISBIS (International Society for Business and Industrial Statistics) 2017 conference, held at IBM Research in Westchester County, and the Domino Data Lab Popup, held in West SoHo. I was invited to speak at ISBIS (slides here, …

This post was originally published on Medium

Occasionally when chatting with other data scientists, especially with others who are interested in integrating predictive models into production software system, the word “scaling” comes up.

Not this. Although some West Coast data scientists are into this kind of scaling …