growth-minded SUPERHEROES
I was interviewed for the growth-minded SUPERHEROES podcast.
Publications
2024
Experiment Nation podcast
I was interviewed for the Experiment Nation podcast.
nohacks.show
I was interviewed for the nohacks.show podcast.
2023
Detecting Interaction Effects in Online Experimentation
In the first two posts in this series, we explained what interaction effects are and what their consequences could be if they remain undetected. We also list...
Avoiding Interaction Effects in Online Experimentation
In the previous post in this series, we defined interaction effects and discussed the potential consequences if they remain undetected. In this post, we will...
Interaction effects in online experimentation
Experiments allow us to test how changes to our products affect the behavior of our users. We make many such changes in many experiments running at the same ...
Analytics Power Hour
I was interviewed for the Analytics Power Hour podcast.
Teachers are also forever learning
This week I learnt that I have been confusing people for years about what a hypothesis really is. A conversation with Erin and Craig helped me understand my ...
Experimentation Masters Podcast
I was interviewed for the Experimentation Masters podcast.
No velocity without speed
Speed is not velocity, but this does not mean that speed is not important. In fact, speed is a prerequisite for velocity: without speed, there can be no velo...
This meeting could have been a wiki page
There is a popular meme which is used as a response to “useless” meetings: “this meeting could have been an email”. I think replacing meetings with emails wo...
Speed is not velocity
“Won’t running all those experiments slow down our product development?” When speaking at conferences, I get this question a lot. And my answer is always the...
2022
Pancakes and experimentation: Learning by doing
We are building a culture of experimentation at Vista. We are taking a scalable, decentralized approach, requiring people and teams across the organization ...
Automated Sample Ratio Mismatch (SRM) detection and analysis
SRM checks are straightforward to automate and can be useful for data quality monitoring even for companies who rely on third-party experimentation platforms.
Time-split testing for pricing optimization at scale
We explain some challenges relating to list prices and more traditional modes of experimentation and we look into which testing capabilities we are building ...
Organising for scaled experimentation
The Experimentation Hub is central to our strategy, but it alone is not sufficient to scale experimentation across our organisation. We will describe the hyb...
1,000 Experiments Club
I was interviewed for the 1,000 Experiments Club podcast.
2021
Building a Culture of Experimentation
I will draw a rough outline of the kind of culture that we are trying to build at Vista, and how we are taking the first steps towards that vision.
Choosing my own adventure
Three things I wanted to experience in my next job
Multiplication instead of division
we will examine in some detail why we consider research and experimentation to be the “peanut butter and jelly” of the customer insights world — two unique t...
Why I am leaving a place I love
FOMO made me do it
How Experimentation Helps You Build Better Travel Digital Products
I was interviewed for the Diggin Travel podcast.
It takes a flywheel to fly
Kickstarting and keeping the A/B testing momentum
2020
Datascience can do what?
I was interviewed for the CRO Cafe podcast.
Gmail Inbox is my to-do-list
How I learnt to stop worrying and made the inbox-as-to-do-list approach work for me.
2019
Understanding Mechanisms of Change in Online Experiments at Booking.com
Mediation Analysis to Disentangle Direct and Indirect Effects
Moving fast, breaking things, and fixing them as quickly as possible
How we use online controlled experiments at Booking.com to release new features faster and more safely
Leaky Abstractions In Online Experimentation Platforms
Categorising Common Challenges
2018
Online Experiments at Booking.com
I was interviewed for the DataFramed podcast.
2013
Predictive Analytics World London
In October I’ll speak at Predictive Analytics World in London. Once again, I’ll be talking about Data Science.
Simulating Repeated Significance Testing
My colleague Mats has an excellent piece on the topic of repeated significance testing on his blog.
Data Science: for Fun and for Profit
In the next few weeks I’ll be giving two talks on the topic of Data Science at Xebicon and another event affiliated with Xebia. There is an abstract of my sp...
A New Kind Of Science?
I am no longer a Corporate Ninja. As of a few weeks ago I can now call myself “Data Scientist at Booking.com”.
Restaurant Reviews and the Availability Heuristic
You could say fine dining is a bit of a hobby of mine; and as I’ve mentioned before, I’ve composed quite a few restaurant reviews over the years. I enjoy wri...
2012
Evidence-Based Everything
I’m not really interested in an exposition of your facts. I don’t very much care to learn about your reasons.
A/B Testing XXL
[I’ve tweeted about this before.]
Actionable Predictive Analytics with Oracle Data Mining
Oracle Data Mining (ODM) provides powerful data mining functionality as native SQL functions within the Oracle Database. This Oracle By Example Tutorial give...
Snake Oil and Tiger Repellant
The Wall Street Journal has an interesting article explaining how companies are starting to use (big) data to support their recruiting efforts. It provides a...
Bin Packing Too Many Features
My girlfriend has been struggling with an interesting little problem lately. She was asked to determine the optimal distribution of medicine boxes and bottle...
Future Felony
Written by Arthur C. Clarke in 1976, Imperial Earth is set in faraway 2276.
Understanding
Derek Jones posits that “success does not require understanding”.
Pitching The Perfect Product Is Not Enough
Marketing catchphrases like “recommended by experts” (an appeal to authority), “world-renowned bestseller” (candidly claiming consensus) and “limited supply ...
Connecting Four in the Cloud
It almost seems like everyone has their head in the cloud these days. And it’s not all just hot air and water vapor. Infrastructure as a service (IaaS), plat...
Combined Likelihood Models in Oracle Real-Time Decisions
[ Crossposting from the Oracle Real-Time Decisions Blog. ]
Decisioni in Tempo Reale
I’ll be chairing a implementation round-table session in Rome next month; involving both customers and partners. Sign up if you want to learn more about impl...
Relevance is Irrelevant
Without fail, a company will employ a recommendation engine for a purpose (nobody does this for fun, really). Often, that purpose is profit (or something alo...
Art-Rock Allegory
Contrary to what it may seem like, I have been busy writing; just not for this particular blog.
The Middle Way
James Taylor is spot-on.
Waterfall Predictions in Oracle Real-Time Decisions
[ Crossposting from the Oracle Real-Time Decisions Blog. ]
Extrapolation
There are two types of people in this world: Those who can extrapolate from incomplete data.
Selling Ice to Eskimos
Facebook has recently discovered that beyond the uncanny valley of personalized marketing lies the bottomless pit of invasive identity misappropriation.
Facet Based Predictions in Oracle Real-Time Decisions
[ Crossposting from the Oracle Real-Time Decisions Blog. ]
Marketing Personalization and the Uncanny Valley
Dear [prospect.first_name],
Analytical Models in Oracle Real-Time Decisions
[ Crossposting from the Oracle Real-Time Decisions Blog. ]
All You Need Is a Good Brainwashing
Classical conditioning is underrated. Too many bad spy movies have taught us that ‘brainwashing’ is bad.
Waste Of Search
Analyzing website traffic can lead to unexpected insights. This incoming search term caught my eye.
Conversion Rates
In my mind, I write a blog post almost every day. But when I sit down to write, I am at a loss for words.
Recording Events
[ Crossposting here from the Oracle Real-Time Decisions Blog where I have been invited to contribute. ]
Placebo Punctuation
I know it’s almost never necessary to use a semicolon, but I like semicolons; they make me feel smart.
Why Metrics Matter
Daring Fireball quotes some interesting research findings related to what Barry Schwartz dubbed The Paradox Of Choice.
From Restaurant Advice To Recommending Associates
After writing restaurant reviews for about a year, I’ve decided to apply my carefully whetted literary prowess to a new type of assessment: recommending peop...
2011
Think Big, Start Small
I ran into the boss of the boss of the boss of the boss of my boss at London City Airport. He did not recognize me of course; there are quite a few Oracle co...
Cornamified Intersite
After consulting the Interwebs, I’ve added a little glitter to my website that will only be revealed to those that know the ways of the Konami code.
Back To Back
Gruber asserts.
Marketers and Accountants
Seth Godin on the topic of perception, memory and marketing concludes.
Predicting Pi
A few weeks ago, I showed a colleague1 my little visual demo of my favorite algorithm for estimating the number Pi. His immediate response was so obvious I a...
Connect Four and Minimax
Computers are incredibly fast calculators. That makes them good at maths, but it does not make them smart. People that program computers have to invent cleve...
Scientific Advertising on Steroids
It seems that my little rant against the apparent lack of scientific rigor and the use of data to analyse performance in the world of advertising is nothing ...
Come on. Learn!
3: Gratuitous use of Flash. It is not Adobe’s fault, it is your fault for using Flash for the most pathetic things mankind has known. Why? Because your...
Intervention
It’s been a while. Too long, to be precise. I did not forget, I’ve simply been postponing writing anything for this blog for days on end. Not that I’ve been ...
Mission Statement
After reading Performance Leadership by Frank Buytendijk it occurred to me that a good mission statement might not only be beneficial for organizations. The ...
Putting the Business back in Business Intelligence
The reason why a large percentage of business intelligence (BI) applications fail is not due to technology. To a large degree these applications fail beca...
Git Busy
I’ve started uploading some of the projects I’ve written about on this blog to Github.
Snakes: Evolution
After one of my previous posts about the snake project Casper had some questions.
Solving Some Sudoku Puzzles Faster (I Stand Corrected)
Okay. So maybe I was jumping to conclusions a little early in the game.
Solving Every Sudoku Puzzle Faster
Peter Norvig’s excellent essay Solving Every Sudoku Puzzle is a fascinating read, and I would highly recommend you read it (or at least scan it briefly) befo...
a Rich Bestiary of Digital Fauna
Speaking of intelligent critters, Wired has an excellent article on the topic.
2010
Snakes on a Two-dimensional Plane
[This post is based around a very old pet project of mine. I thought it worthwhile to describe this golden oldie some more detail and relate it to my current...
Monkeynomics
Just like with the real coccyx, we should expect to see analogues to the legacy artifacts discussed in a previous post in other animals sharing recent evolut...
More Pi
In a previous post I’ve explained how we can estimate the number Pi using Monte Carlo Methods (basically throwing darts at a circle). I personally think this...
a Coccyx in the Brain
You might not realize it, but your brain is running some pretty wonky legacy code. Stuff that worked fine back in the day, but is not very well suited for th...
Blogging with the Stars
I started a blog because I wanted to improve my writing skills; and thought I had something to say. You, as a reader can help me figure out how I am doing by...
The Curse of Getting Things Done
I consider myself to be well organized. Both in my professional and personal life I use Remember the Milk for keeping track of almost everything I do using s...
the Moral of a Good Story
I love reading. I love reading about statistics. I love reading about psychology. But most of all, I love reading quite a few books about statistics and psyc...
a Free Tip
A representative of a large company (which shall remain unnamed) recently called on me for some advice. They had accidentally loaded polluted data into their...
the Same Old Song
[I’ve tweeted about this before.]
the Trick to 42
Frank Buytendijk, in his book Performance Leadership, writes the following. Most people I asked, and most sources I referred to, define an organization si...
Copying Bits in the Fastlane
I’ve finally gotten ‘round to rooting my ‘old’ G1 phone and installing the Cyanogen firmware. I will not bore you with the technical details of flashing firm...
One Step Closer to the Cloud
Because of the continuing lack of internet connectivity at my new address I’ve decided to move my website from my own server to the free space provided by my...
Benford’s Law Revised
After posting my previous article I started wondering why my transactional data contained a disproportional amount of twos. Something must be distorting the ...
Benford’s Law
In a (not so) recent episode of Radio Lab (one of my favorite podcasts) I was introduced to Benford’s Law. I’d never heard of this phenomenon, which in hinds...
a Database is not a Box
I’ve seen people using and building upon databases in lots of different ways; many of them surprisingly original. However, it seems to me that some people do...
I am a Corporate Ninja
At first, the term Business Intelligence (abbr. BI) had me a bit confused. Contrary to my initial interpretation, BI does not concern the mental acuity of co...
Estimating Pi
[I’ve tweeted about this before, but I feel the need to explain.]
It’s about time I started a blog.
It crossed my mind before, but I never felt I had anything to say. I want that to change.
