Sean J. Taylor Profile Banner
Sean J. Taylor Profile
Sean J. Taylor

@seanjtaylor

Followers
46,192
Following
4,240
Media
971
Statuses
18,982

Building @MotifAnalytics . Formerly @Lyft and @Facebook . Keywords: Experiments, Causal Inference, Statistics, Machine Learning, Economics.

Oakland, CA
Joined February 2009
Don't wanna be here? Send us removal request.
Explore trending content on Musk Viewer
Pinned Tweet
@seanjtaylor
Sean J. Taylor
11 months
I was stoked to get some data from Bluesky and start to play around with it in @MotifAnalytics . Check it out and see how much you can do (from scratch!) in ten minutes, when you have the right abstractions for working with sequences.
8
8
73
@seanjtaylor
Sean J. Taylor
3 years
Here’s my trick.
Tweet media one
62
785
6K
@seanjtaylor
Sean J. Taylor
2 years
I can’t understand how this can sound so ridiculous and yet be totally reasonable advice Credit:
59
800
5K
@seanjtaylor
Sean J. Taylor
4 years
Reading through the Wolfram announcement I had a startling realization about the nature of the universe.
Tweet media one
Tweet media two
Tweet media three
Tweet media four
90
518
4K
@seanjtaylor
Sean J. Taylor
4 years
You can only keep three.
Tweet media one
197
601
4K
@seanjtaylor
Sean J. Taylor
3 years
When I left Facebook, I had interviewed around 350 data scientists. I'm close to 100 interviews now at Lyft. I feel like I could write a book about what I've learned; what would be most interesting to read about? Do you think it's ethical to share themes and lessons learned?
163
79
3K
@seanjtaylor
Sean J. Taylor
6 years
If you read a paper or blogpost and find it useful, a nice thing to do is write a quick email to the author and tell them. Writing long-form technical content is so much work and I think authors probably systematically underestimate how much value they create.
37
616
3K
@seanjtaylor
Sean J. Taylor
5 years
When I'm showing someone my latest results by walking them through a Jupyter notebook.
Tweet media one
16
351
2K
@seanjtaylor
Sean J. Taylor
3 years
Data science is not actually a science.
118
215
2K
@seanjtaylor
Sean J. Taylor
2 years
I love this graphic. Such a tidy way to think about it.
Tweet media one
22
193
2K
@seanjtaylor
Sean J. Taylor
3 years
Fool me once, shame on my prior. Fool me twice, shame on my likelihood.
11
129
2K
@seanjtaylor
Sean J. Taylor
3 years
One thing computers are really good at is telling you how many seconds have passed since January 1st, 1970.
25
86
1K
@seanjtaylor
Sean J. Taylor
3 years
Almost every problem in my life can be traced to an unfounded optimism about how quickly I can get things done and how many things I can do at once.
17
99
1K
@seanjtaylor
Sean J. Taylor
3 years
Perhaps my most controversial opinion: In machine learning education, the focus on supervised learning and particularly on classification problems gives people a totally misguided idea about how to use data to solve real problems.
39
148
1K
@seanjtaylor
Sean J. Taylor
5 years
Some personal news: I'll be leaving my role at Facebook in two weeks. I can't say enough positive things about the company and my fantastic co-workers. On 5/20, I'll start at Lyft as head of research science for the Decision Science Products team. Excited for the journey ahead!
84
29
1K
@seanjtaylor
Sean J. Taylor
1 year
Two of the hardest things about cognitively demanding work are: 1) You can’t really make it go faster. There are tricks to getting unstuck but it usually proceeds very nonlinearly. 2) It often looks like it could have been done in a far shorter amount of time when it’s over.
23
137
1K
@seanjtaylor
Sean J. Taylor
4 years
I often ask data scientists for examples of projects that went poorly or where they have regrets. The most common answer by far: agreeing to work on a question they didn't think could be well-answered with their data, then having the caveats/nuances ignored by decision makers.
30
228
1K
@seanjtaylor
Sean J. Taylor
6 years
I'm as enthusiastic about the future of AI as (almost) anyone, but I would estimate I've created 1000X more value from careful manual analysis of a few high quality data sets than I have from all the fancy ML models I've trained combined.
19
328
1K
@seanjtaylor
Sean J. Taylor
3 years
Another week, another re-read of @karpathy 's timeless recipe for training neural networks, perhaps the article that's saved me the most time in aggregate.
9
165
1K
@seanjtaylor
Sean J. Taylor
5 years
📈Long thread on how Prophet works📈 - Instead of sharing slides I'm transcribing my talk to tweets with lots of GIFs :) - Thanks to @_bletham_ for all his help.
24
335
1K
@seanjtaylor
Sean J. Taylor
3 years
If I could more realistically estimate how long my projects were going to take I probably wouldn’t start any of them.
24
95
1K
@seanjtaylor
Sean J. Taylor
4 years
My old data science team at Facebook would formally acknowledge a type of impact we called "preventing a doomed course of action." I love this phrase and the idea that you need to encouraging people to actually *stop* projects when there's too little upside or too much risk.
18
138
1K
@seanjtaylor
Sean J. Taylor
5 years
I recently got a copy of "W. E. B. Du Bois's Data Portraits: Visualizing Black America." Totally floored by the craft, artistry, and intention in this project. These plots were drawn in the *1890s* based on painstakingly collected data & told an important story we'd have missed.
Tweet media one
Tweet media two
18
266
1K
@seanjtaylor
Sean J. Taylor
5 years
I think this is an interesting topic but found this visualization hard to follow (no surprise if you've been reading my complaints about animated plots). I have nothing to do tonight so i'm going to try to re-visualize this data. Starting a THREAD I'll keep updated as I go.
@flowingdata
Nathan Yau
5 years
How commuting is too much? It depends on where you live.
1
46
143
20
200
1K
@seanjtaylor
Sean J. Taylor
6 years
Why I've transitioned from social science research to working on methods and tools: Me: (presents social science research) People: We disagree about the findings, interpretation, and importance. Me: (builds and shares a tool) People: Thanks, this is awesome and useful.
19
142
958
@seanjtaylor
Sean J. Taylor
4 years
Probably the most productivity-improving thing you do can for a data science team is to create and maintain a strong, inclusive community of practice. If people on your team aren’t constantly learning from each other, you’re leaving a ton of value on the table.
10
241
957
@seanjtaylor
Sean J. Taylor
7 years
Prophet is an open-source forecasting package implemented in both Python and R, used in production at Facebook:
17
318
906
@seanjtaylor
Sean J. Taylor
5 years
If you want to question whether human-produced labels for training ML models represent "ground truth," look no further than the sheer volume of misclassifications in a pair of recycling/trash bins.
16
221
904
@seanjtaylor
Sean J. Taylor
5 years
We fail to reject the null hypothesis that Taco Bell distributes sauce packets with equal probability (p = 0.947).
Tweet media one
24
150
835
@seanjtaylor
Sean J. Taylor
3 years
Imagine if every technical blog post started with a few paragraphs of inane personal anecdote and put the code in a small box at the very bottom.
29
41
850
@seanjtaylor
Sean J. Taylor
3 years
One useful mental model for statistics: every bit of certainty you achieve has to either be earned with data or bought with assumptions, and you don’t often know how much the assumptions have cost you.
6
120
823
@seanjtaylor
Sean J. Taylor
7 years
+ geom_nonsense()
Tweet media one
27
250
812
@seanjtaylor
Sean J. Taylor
3 years
One stark difference between R and Python. If I'm looking for a good natural spline implementation: R: I can directly import `splines` which Douglas Bates has been working on for 22 years. Python: google/copy/paste some snippet from StackOverflow and pray that it's correct.
36
49
772
@seanjtaylor
Sean J. Taylor
5 years
A couple days ago another team asked me to speak about Bayesian data analysis. I decided that instead of doing a nuts/bolts of how to fit/use Bayesian models, I would describe "Bayesian analysis: The Good Parts". <potentially controversial thread>
17
212
760
@seanjtaylor
Sean J. Taylor
2 years
Often people say “I’m not good at X” when they really mean “I’m not good at tolerating the negative feelings I experienced when I was trying to learn X.” For me it’s learning languages. Being a beginner at stuff is frustrating, embarrassing, jealousy-inducing, and even hopeless.
11
64
765
@seanjtaylor
Sean J. Taylor
5 years
Imagine being an expert on causal inference and concluding from all available evidence that hundreds of smart people aren’t using your methods because they’re too stubborn and the policy implication is you need to tell them that on Twitter everyday.
20
66
748
@seanjtaylor
Sean J. Taylor
3 years
has one of my absolute favorite data visualizations.
Tweet media one
26
70
738
@seanjtaylor
Sean J. Taylor
2 years
One of the best parts about not being an academic is having a positive response to learning that someone’s already written about idea I just had, as opposed to being completely demoralized.
13
37
735
@seanjtaylor
Sean J. Taylor
4 years
I've been reflecting a lot on why data science is so hard to do well. My current mental model: value is generated multiplicatively. You must get each thing right or it's worth almost nothing: - Formulate good questions - Quality data - Correct analysis - Communicate findings
21
150
710
@seanjtaylor
Sean J. Taylor
5 years
This new paper clustering the global labor network is really rad. It's cool how much structure pops out when you apply the right model. Great work @vagabondjack @yy et al.!
Tweet media one
10
197
698
@seanjtaylor
Sean J. Taylor
6 years
Incredible work on Bayesian Optimization by my colleagues on Facebook's Adaptive Experimentation team. This is the next generation of A/B testing.
3
170
683
@seanjtaylor
Sean J. Taylor
3 years
Sometimes I think the most important skill is knowing how to find information resources: knowing the right places to look, the right queries to use, the right people to ask, efficiently skimming writing, and then persevering when your process doesn't yield easy results.
18
91
687
@seanjtaylor
Sean J. Taylor
2 years
Yesterday was last full time day at Lyft, though I’ll remain in a part-time advisory role. I’m grateful for three years filled with kind and talented people, intellectually stimulating problems, & many valuable lessons. Ten years into my tech career, it’s time for a little break.
35
2
668
@seanjtaylor
Sean J. Taylor
3 years
The sheer faith required to build a data science team. “Let’s hire a bunch of expensive and hard to recruit employees and have them help us get value out our data!” “How will we know if it’s working?” “That’s easy, we’ll hire more of them to tell us.”
13
61
659
@seanjtaylor
Sean J. Taylor
3 years
Just trying to get an answer to my dumb stats question without judgement like everyone else and how's this supposed to make me feel Glen???
Tweet media one
32
16
664
@seanjtaylor
Sean J. Taylor
3 years
At Lyft we have a special implementation of gradient boosted trees for dealing with spatial data called GeoBoost. Here's how it works!
Tweet media one
7
107
654
@seanjtaylor
Sean J. Taylor
2 years
A/B testing is just stochastic gradient descent for companies.
13
49
642
@seanjtaylor
Sean J. Taylor
4 years
When you start your research project with a data set rather than a research question.
13
145
649
@seanjtaylor
Sean J. Taylor
4 years
This is amazing -- you can fit a model in R and then export to a runnable SQL statement, so scaling your prediction step is done by your database! Supports GLMs and many tree-based models.
@topepos
Max Kuhn
4 years
@calvinmdewilde @rstatstweet Already done for a few models:
Tweet media one
4
26
146
8
113
641
@seanjtaylor
Sean J. Taylor
3 years
What software are people using to draw those fancy neural network architecture diagrams? Surely they aren’t doing this by hand...
26
66
618
@seanjtaylor
Sean J. Taylor
5 years
In the spirit of sharing professional failures in addition to successes: Today I had a paper rejected from a journal. It's the second journal that gave us a R&R and then rejected the revision. I've been working on this paper since 2013 and am still damned proud of the research.
20
44
628
@seanjtaylor
Sean J. Taylor
3 years
Probably the most important skill you can have is the ability to get a big group of people to agree to working on the same thing for a prolonged period of time.
8
62
619
@seanjtaylor
Sean J. Taylor
5 years
Your first attempt at fitting a curve might be a polynomial. You can see that as you add terms you can *interpolate* better but the *extrapolation* is very poor. This is because the local trend it is estimating is usually very wrong.
5
173
620
@seanjtaylor
Sean J. Taylor
3 years
One weird thing about data science is that the plot you’re showing someone in your slides either takes ten times as much time as they think or a tenth of the time, but often not in between.
10
63
614
@seanjtaylor
Sean J. Taylor
2 years
Right after that amazing feeling of getting your code to work, there's this awful moment where you realize how much clean up it needs before anyone can possibly be allowed to see it. It's like reckoning with the mess in your kitchen after cooking a big meal.
11
37
619
@seanjtaylor
Sean J. Taylor
5 years
Someone just *called my phone* for help with my open source software. Never, ever, ever, ever do this.
37
50
607
@seanjtaylor
Sean J. Taylor
4 years
Tools/techniques that made exploratory data analysis in Python way better for me: 1) Leveling up on method chaining in Pandas: 2) Using Altair for plotting: 3) Using nb_black to clean up notebook code:
9
121
601
@seanjtaylor
Sean J. Taylor
1 year
A friend just asked "didn't you work at the Fed?" Yes. But as for implied expertise, let me explain: I was an RA. Alan Greenspan liked the scenario forecast lines to be colors that our software couldn't output. My most important job was to manually alter the plots in CorelDraw.
19
33
585
@seanjtaylor
Sean J. Taylor
4 years
Domestication is crazy. Kale, broccoli, brussels sprouts, and cabbage are all the same species, brassica oleracea.
Tweet media one
11
105
560
@seanjtaylor
Sean J. Taylor
4 years
It's amazing how much data processing code goes away when your data is stored appropriately (usually tidy). Often, I can delete half my code once I figure out how I should have reshaped the data. Corollary: when I'm writing a lot of code, I rethink how I've arranged the data.
12
54
551
@seanjtaylor
Sean J. Taylor
2 years
Professional news! I’ve joined @MotifAnalytics as co-founder and chief scientist. Building a company and a product is a new challenge for me. Just a few weeks in I can tell it’s going to be a ton of fun. Thanks to @mikpanko and Theron Ji for letting me join their awesome team!
49
16
543
@seanjtaylor
Sean J. Taylor
3 years
Slack is just like twitter except if every tweet is someone asking me to do something, I’m not allowed to unfollow anybody, and I lose my job if I don’t use it.
9
44
547
@seanjtaylor
Sean J. Taylor
4 years
One time, I had to estimate a confidence interval for a sample estimate and there was no convenient formula for analytic standard errors. #IBootstrapped
@caroljsroth
Carol Roth
4 years
Did you bootstrap your way to success? Reply to this w your story & #IBootstrapped
540
164
832
5
32
545
@seanjtaylor
Sean J. Taylor
5 years
What are the most interesting parts of building a ML classifier? 1. feature engineering 2. label engineering 3. experimenting with different models 4. hyperparameter tuning 5. summarizing/explaining model performance 6. automating training and deployment 7. <something I missed>
67
116
525
@seanjtaylor
Sean J. Taylor
5 years
The adult version of the marshmallow test is whether you wait until the pizza cools before eating or knowingly scorch the roof of your mouth.
27
57
527
@seanjtaylor
Sean J. Taylor
2 years
The most grad student thing I’ve done in awhile, today I emptied all my soy sauce packets from several months of delivery orders into a measuring cup and refilled my soy sauce bottle. Hard to beat this feeling.
17
3
534
@seanjtaylor
Sean J. Taylor
5 years
Holds up perfectly over four years later.
@seanjtaylor
Sean J. Taylor
9 years
Tweet media one
2
58
259
12
74
519
@seanjtaylor
Sean J. Taylor
4 years
We should always have an emergency task force of people with exceptional GRE scores at the ready. Whenever there's an urgent need for advice from experts in a well-established academic field, they can sub in and rediscover all their key empirical and theoretical results.
13
27
521
@seanjtaylor
Sean J. Taylor
6 years
Big news -- our team at Facebook is awarding $150K in grants for applied statistics research! Deadline for proposals is Oct 30th. Please share! Topics include: - experimentation - sampling - surveys and nonresponse bias - forecasting - causal inference
14
345
515
@seanjtaylor
Sean J. Taylor
3 years
Recruiters.
Tweet media one
21
10
509
@seanjtaylor
Sean J. Taylor
3 years
Confessions of a very applied statistician (a thread)
2
89
497
@seanjtaylor
Sean J. Taylor
4 years
Would be useful in a world where writing code were the main hard part of software engineering.
@Altimor
Flo Crivello
4 years
GPT3 writing code. A compiler from natural language to code. People don't understand — this will change absolutely everything. We're decoupling human horsepower from code production. The intellectual equivalent of the discovery of the engine.
Tweet media one
95
429
1K
19
57
495
@seanjtaylor
Sean J. Taylor
4 years
My team has used this idea (in PyTorch🔥) to ensure that models are consistent with various economic and business assumptions (e.g. diminishing marginal returns). It can improve quality and training requirements by not forcing your model to learn easy-to-articulate structure.
@TensorFlow
TensorFlow
4 years
Control your ML with common-sense shape constraint! We’ve just released TensorFlow Lattice 2.0 for training flexible and interpretable ML models powered by domain knowledge. 💡Check it out →
Tweet media one
1
135
484
6
91
494
@seanjtaylor
Sean J. Taylor
5 years
Succeeding as a data scientist in small companies/startups (fantastic post by @Randy_Au )
9
117
487
@seanjtaylor
Sean J. Taylor
5 years
We released Prophet 0.4 today! Thanks to all the wonderful contributors ❤️ Prophet can now automatically generate lists of holidays for over a dozen countries. Just in time for the holidays 🕎🎄😜 Install: Built-in holiday docs:
Tweet media one
Tweet media two
Tweet media three
11
126
479
@seanjtaylor
Sean J. Taylor
3 years
Maybe Google can build a 10B parameter deep learning model to predict with high accuracy THAT I NEVER WANT TO USE MAPS FROM MY WORK ACCOUNT.
14
20
461
@seanjtaylor
Sean J. Taylor
5 years
A Python dataframe that implements something close to the dplyr API, entirely backed by SQLite (no Pandas or Numpy): (Kind of a weird thing I was hacking on this weekend)
Tweet media one
14
92
463
@seanjtaylor
Sean J. Taylor
4 years
It's funny to think about how in the early days of the web, people worried Wikipedia would be filled with terrible information because anyone could edit it. Now it's basically the only resource left that I'll trust without hesitation.
15
41
457
@seanjtaylor
Sean J. Taylor
4 years
Wrong answers only
@dontsave
dave
4 years
why hasn't anyone stopped the virus with Machine Learning
132
512
4K
217
90
452
@seanjtaylor
Sean J. Taylor
4 years
Here's a nice paper about why this idea is extremely appealing and completely wrong:
@rabois
Keith Rabois
4 years
@jbjakub @zachweinberg with very large numbers of n’s you don’t need randomization.
52
4
37
12
64
453
@seanjtaylor
Sean J. Taylor
3 years
In many cases, the secret to finishing a project is just changing your definition of what being done means.
10
35
452
@seanjtaylor
Sean J. Taylor
4 years
When your learning rate schedule is perfect.
2
59
445
@seanjtaylor
Sean J. Taylor
4 years
I'm procrastinating tonight so I'll share a quick management tool I use. It's close to the end of H1 so performance reviews are coming. I tell this to my reports: "Your work is going to be distilled into a story, please help me tell a good one so I can represent your work well"
11
67
444
@seanjtaylor
Sean J. Taylor
3 years
When you encode your vectors as strings.
2
36
434
@seanjtaylor
Sean J. Taylor
3 years
Folks have asked me for references on the ML perspective on causal inference. Here are two good ones: 1. @matheusfacure 's book "Causal Inference for the Brave and the True" (Part II) 2. @CasualBrady 's lecture notes (Chapter 7)
4
88
438
@seanjtaylor
Sean J. Taylor
4 years
For a sufficiently small/biased sample, the most important factors are things experts already know and the next set of factors you learn are probably noise and unlikely to generalize. In other news, I look forward to the release of 19 new Marvel movies this summer.
@DiscussingFilm
DiscussingFilm
4 years
Warner Bros has signed a deal for a AI-driven film management system which will help decision-making for greenlighting certain films. The AI system can assess an actor’s value in any territory and how much a film is expected to earn in theaters. (Source: )
Tweet media one
2K
1K
4K
16
44
437
@seanjtaylor
Sean J. Taylor
6 years
Incredibly useful reference on gradient descent optimization algorithms: I've been reading up on these algorithms for a project and the literature is SO dense and math-y. So thankful to @seb_ruder for synthesizing it clearly and providing pseudocode.
3
112
434
@seanjtaylor
Sean J. Taylor
6 years
If you're deploying Python code in production you probably want to know about XAR, a new open source project that lets you package many files into a single self-contained executable file:
7
127
428
@seanjtaylor
Sean J. Taylor
4 years
If you're a data scientist who works with not-so-technical stakeholders, how do you think about getting them to listen to you, trust your analysis, and follow your suggestions? Especially when they may have strong opinions based on small samples or more limited evidence.
89
69
434
@seanjtaylor
Sean J. Taylor
5 years
New working paper: "Active Matrix Factorization for Surveys" w/ Chelsea Zhang, Jas Sekhon, & Curtiss Cobb We ask fewer questions and impute missing responses via probabilistic matrix factorization, choosing questions sequentially using active learning.
Tweet media one
Tweet media two
Tweet media three
Tweet media four
7
99
428
@seanjtaylor
Sean J. Taylor
3 months
Today I saw the release of a previously unimaginable text to video AI model and also a new python package manager, and it’s a very close race to determine which one is more impressive to the nerd community.
10
20
425
@seanjtaylor
Sean J. Taylor
4 years
My favorite part here is the distinction between “average” and “not bad,” which have the same mode but convey drastically different information about how much certainty you have about it.
@dsquintana
Dan Quintana
4 years
How does “Perfect” NOT have an average score of 10?
Tweet media one
54
260
1K
14
90
417
@seanjtaylor
Sean J. Taylor
6 years
"No one believes an hypothesis except its originator but everyone believes an experiment except the experimenter." - W. I. B. Beveridge (The Art of Scientific Investigation)
2
119
416
@seanjtaylor
Sean J. Taylor
5 years
@_bletham_ Have you seen:
Tweet media one
7
81
408
@seanjtaylor
Sean J. Taylor
3 years
This post rips Prophet (a forecasting package I helped create) to shreds and I agree with most of it🥲 I always suspected the positive feedback was mostly from folks who’d had good results—conveniently the author has condensed many bad ones into one place.
12
58
414
@seanjtaylor
Sean J. Taylor
3 years
Minor job announcement: I am no longer Head of Rideshare Labs at Lyft, I handed off most of my people management to a great manager who’s going to do a better job than I was. I’ll get more hands-on work and focus time, which I hope will help accelerate some exciting projects.
16
4
414
@seanjtaylor
Sean J. Taylor
3 years
The worst part about tweeting is that all your personal and professional connections know damned well you’re procrastinating on replying to their emails.
13
15
410
@seanjtaylor
Sean J. Taylor
2 years
In other bad financial news, I accidentally drank one of the bottles of spring water in my hotel room thinking it was complimentary.
16
6
408
@seanjtaylor
Sean J. Taylor
6 years
Gonna start inverting loss functions and calling them win functions to see if I can make statistics more positive.
22
60
395