How to pick a successful AI project, part 1: Finding the problem and collecting data

This post is part of a series on ‘how to pick a successful AI project’. Part 2, Part 3.

Imagine that you have 200 hrs of your life to improve your career prospects in ML. What is the best use of this time? I’m betting on doing a portfolio project.

Let’s compare different options:

1. You could go to meetups

2. You could do tutorials, follow template code and be the Github user # 2245 who has this same exercise

3. You could take classes or MOOCs

Option 1 relies on serendipity. Assume you meet a potential job opportunity every 5 meetups (which could be a bit optimistic!) You may well spend a year going to meetups and getting exactly zero job opportunities if:

  • you are not looking amazing on paper/online, and
  • you don’t communicate very well in person

Assuming commuting to and attending the meetup takes 5hrs, How many meetups can you do? 40. That’s 20 conversations worth having. Still, without some strong signal that you can perform (such as work experience, or a tangible ML project you built from scratch), you will not convert these random conversations into job offers.

Options 2 and 3 (tutorials and MOOCs) don’t differentiate you enough from the masses. They are a prerequisite to reaching the level that would make a hiring manager take notice. Because work experience is hard to get when you are trying to get into a new field (chicken and egg problem) that leaves you with my preferred option, and the reason I wrote this series of posts: show the world what you can do by having an AI portfolio project.

A substantial project strongly dominates the other options

Once I asked Ted Dunning: “What is the one thing you care about as an interviewer?”. His answer: “I only care about one thing: What you have done when nobody told you what to do.”

Having a portfolio of projects shows creativity, which is extremely important in data problems.

Data cleaning, even model fitting, is somewhat grunt work. We will likely automate this in the future.

What is not automatable (and where you want to excel) is at:

• finding a problem

• That is worth solving (produces business value; helps someone)

• and is solvable with current tech

Ok, so you want to do a good AI project

The rest of this post is what I’ve learned after mentoring more than 150 AI projects over five years at the companies I’ve founded.

I’ve grouped what I know into four classes:

• Finding the problem

• Collecting data

• Working with data

• working with models

Finding the Problem

What human task is your project helping or displacing? If the task’s decisions take longer than a second for a human, pick another one

Machines are good at helping humans with boring tasks. The rule of thumb (from Andrew Ng) is that you want to tackle tasks that take a human less than one second. Driving, for example, is a long series of sub-second decisions. There’s little deep thinking there. Writing a novel is not like that. While NLP progress may look like we are getting closer and closer, writing a novel with AI is not a good project.

Myth: you need a lot of data. you need to be google to get value out of machine learning

When looking for problems, you are looking for data too. Often you feel there’s no data to address the problem you found. Or not enough data. Data is valuable, and those who have data don’t make them public. There’s plenty of public data, but nothing that matches what you need.

You come up with hacks, of course. Maybe you can combine different sources? Maybe you generate and label the data yourself?

Then you read online that you need giant datasets. You are screwed. You are not going to label millions of images just by yourself.

It’s true that for very complex deep learning models, you need those giant datasets. An excellent boost for ML in the 21st century is that now we have lots more data, and compute power, to train more complex models.

Many of the revolutionary results in computer vision and NLP come from having a lot of data.

Does this mean that you cannot do productive machine learning if you have no big compute clusters or datasets in the Terabyte range? Of course not.

Libraries contain pretrained models (like Inception V3, ResNet, AlexNet). You can use then to save computation time.

Take, for example, YOLO (you only look once). Anyone with an off the shelf GPU can do real-time object detection and segmentation in video. That is amazing. How many projects can you conceive with this feature? Make it an exercise: list 10 projects that you could build based on YOLO. By the time you read this, it’s likely there’s a new algorithm that does the task better. It’s a beautiful time to be alive. You don’t need terabyte-sized datasets to get value off of machine learning.

Pick a problem that passes ‘the eyebrow test’

The skill of picking a problem is as useful as the skill to solve it. Some problems will capture your imagination, and some will leave you unmoved. Pick the first.

And then there are those projects that make people think that what you are saying is impossible. You want one of those.

How do you know you picked the right problem? Use ‘the eyebrow test.’ You want to see the eyebrows of the other person going up when they hear it. If they don’t, keep looking.

Some problems are mere curiosities and can suck your resources. Don’t go for those. There’s tremendous potential for impact using ML right now. Why spend your time creating a translation algorithm from Klingon to Dothraki (both invented languages) when you can make people’s lives easier?

At Data Science Retreat we believe that because there are plenty of ‘good problems,’ there’s no excuse to pick one that doesn’t pass the eyebrow test. It takes time to find a good problem. How long should you spend? As much as needed to pass the eyebrow test.

It helps if you are in the surroundings of people who have found a good problem before. Sometimes, those with deep domain knowledge in ML are not as useful as you may think to pick up ideas.

You are selling the value of AI. When you do ‘eyebrow test’ projects, you help not only the people-who-have-that-problem (always keep them in mind) but… your fellow data scientists. The more impressive your projects are, the more the general public will appreciate how transformative AI is for society. And the more opportunities you create for everyone else in the field.

You only need to be in the ballpark of a good idea

One participant came to me saying that he was running late to pick up an idea and that he had exhausted all his possibilities. He had nothing.

“Ok, let’s look at what you are passionate about. What’s alive in you?”

“Well,… I hate waste.”

So we googled ‘waste trash machine learning.’ Nothing too obvious, nor too exciting, came about. After some more search, we found a Stanford project that categorized trash. The students had a trash dataset, painfully labeled. Still, this was not exactly an idea that passes the ‘eyebrow test.’

“What if instead of categorizing trash, we could build something that picks up trash?” (iterating on the idea)

“You mean something that goes around autonomously?”

“Yes, a self-driving toy car. There was one project in batch 08 of DSR that did exactly that. The car ran laps on a circuit. You would have to modify it to identify trash, get close to it, and pick it.”

“That sounds amazing!” (eyebrow test passed)

With time, this ballpark idea morphed from general trash to picking up cigarette butts, which are terrible for the environment. Details about how to pick the cigarette butts improved with time: stabbing them, instead of trying to grab them with a robotic arm. We will talk more about this project later in this series.

Pick a problem that moves you. If nothing does, use ‘watering holes’ to listen to problems that move people

If you have the problem you want to tackle, you have a significant advantage. You understand the need. You can build the solution and know how well it works by applying it to yourself. You can tell between ‘nice to have’ and ‘pain point.’ At this point, what we are doing is no different from what startup founders and product managers do.

You have in your hands the closest thing to a shortcut: have the problem yourself. You will save time but not going into detours that don’t help. You will have a keen sense of what to build.

In 2014 I was building a company that eventually failed doing customer lifetime value (CLV) predictions for e-commerce stores. The product CLV predictions, though, was something I could deliver myself as a consultant. So I became a ‘CLV consultant.’ One of my clients was hiring a data scientist, and they hired me fulltime, so I magically transitioned into data science.

Many others had the same problem: they had tech skills, maybe a Ph.D., and they wanted to become data scientists, but they didn’t know how. Remember, this was 2014, before the web started boiling with advice on how to become a data scientist. I built a business around helping others solving this problem, and it’s been working well for the last five years.

I knew well what the problem is; too much information, unclear guidelines, interviewers who don’t know how to recognize talent. Every step of the way, I felt I knew what I was doing with this business; a feeling that is extremely valuable. Transitioning to data science is an excellent problem; 5 years later, people still struggle with it.

I don’t play golf. If I wanted to build a product for golfers, I’d be lost entirely. I would build features nobody need; I would miss the pain points. Even if I ran interviews and listened to the market, I would at a disadvantage to a golfer.

So my advice to pick a portfolio project: pick a problem you know well. Even better if it’s a problem that moves you. If you lost three friends to suicide, build something to prevent suicide. In this case, you don’t have the problem yourself, but you have a strong motivation to solve it.

What if you have no problems whatsoever? You have been in the same industry forever (say Oil and Gas), and all valuable problems there got taken care of!

I don’t believe you. There’s no industry so mature that all problems are solved. But, ok, you cannot come up with something that moves you, some problem that you have.

Then observe what problems other people have. Large groups of people. They tend to congregate in public spaces and bitch about their problems; every time you see people bitching about something… turn that into an opportunity to do a project.

Which public spaces? I call these ‘watering holes’ (HT to Amy Hoy). Online, you can have obscure forums, but Reddit and twitter are the easiest. Just sit there and ‘listen’ to people discuss the problem. Learn every detail of it. Is it a real problem, or a ‘nice to have’?

For example, you may join a gaming subreddit to see if gamers care about having stronger AI in videogames. Or if they care for VR. These ideas are too abstract to be good project ideas, but you get where I’m going.

Collecting data

Integrate distinct data sources

Often companies are so focused on getting value out of the data they have they forget they can increase value using the data not in their company but publicly available.

There’s plenty of open access data. And APIs for data that changes frequently. There’s no reason not to use multiple data sources. You can solve a more interesting problem (one that was not obvious before) by integrating APIs.

For a collection of APIs, check

Problems that seemed impossible with a single source of data become solvable when you add a new data source. Boring projects come alive. Thankless tasks become a joy to work with if you manage to find a twist that shows more value.

When using multiple data sources, you have to stitch them together using a shared key (a column that is present in both datasets.) You cannot combine data sources that don’t have a shared key, and that tends to be a showstopper for many ideas.

Instead of collecting or reusing data, produce your own data

You don’t need to find data, or own it. Thanks to pretrained models (see later section on them), you don’t need all that much data, which means you can produce it yourself. Removing “I don’t much/any data” as an obstacle opens up the space of problems you want to solve.

To produce original data, I found one big hack: use hardware. Sensors are cheap, and they give you data that you own.’s Shanghai fulfillment center uses automated warehouse robotics to organize, pick, and ship 200k orders per day. 4 human workers tend the facility. grew its warehouse count and surface area 45% YoY. AI affects manufacturing too. It’s easier than ever to produce things en masse, and this means there are a lot more hardware ‘toys’ in the market. Things that you would never consider to be affordable like microscopes, spectroscopes are reaching the mass consumer market and are eminently hackable. These are wonderful data sources!

Because of Shenzhen, Kickstarter, etc. hardware is evolving far faster than before. It’s never going to be as fast to iterate on as software, but we are getting there. Have you checked what’s available on Ali express? There are multiple sensors you can buy for under 100 bucks. Attach one of these to a phone running your code, and you have a portable purpose-specific machine.

For example, you can buy a microscope and use it to detect Malaria without a human doctor. Deep learning running on a phone is good enough to count parasites on blood.

Ali express is full of cheap hardware that you can attach to a phone. You can add a lot of value to someone’s life using a mixture of phones (that run the ML code) and

Example: our Malaria Microscope.

Eduardo, AIscope’s founder, after reaching 1000x the first time

Malaria kills about 400k people per year, mostly children. It’s curable, but detecting it is not trivial, and it happens in parts of the world where hospitals and doctors are not very accessible. Malaria parasites are quite big, and a simple microscope can show them; the standard diagnostic method involves a doctor counting them.

It turns out you can attach a USB microscope to a mobile phone, and run DL code on the phone that counts parasites with accuracy comparable to a human. Eduardo Peire, DSR alumni, started with a pubic Malaria dataset. While small, this was enough to demonstrate value to people, and his crowdfunding campaign got him enough funds to fly to the Amazon and collect more samples. You can follow their progress here:

For another example, you can buy a spectroscope that pointed at any material, and it’d tell you its composition. It’s small enough to attach to a phone for a hand-held scanner. Can you detect traces of peanuts in food? Yes! There you go, a solution to a problem real people have. If you are allergic to peanuts, this will buy you a certain quality of life.

Sensors are cheap nowadays, and they will help you get unique data. You can turn a phone into a microscope, a spectroscope, or any other tool. The built-in camera and accelerometer are excellent sources of data too.

Next on this series: what I’ve learned about working with data and how this can help you pick successful AI projects.

How to pick a machine learning project that would get you hired

I’ve mentored about 165 projects during the last five years at the companies where I work. The people who built those project all got jobs (mostly). The more I talk to companies interviewing today, the more apparent it is: A portfolio project is decisive when making hiring judgments. Jeremy Howard recommends it. Andrew Ng recommends it. Why? It’s far better at discriminating talent than any other proxy (CVs don’t work; pedigree doesn’t work; puzzles don’t work).

And yet, the proportion of people who finish MOOCs AND have a portfolio project is tiny. What’s the catch?

Well, it could be that these are orthogonal skills. Finishing something as demanding as a deep learning MOOC (or a uni degree) show that you have grit. You can start and finish difficult, demanding projects. But what hiring managers want to know is: “What did you do when nobody told you what to do?”, “Can you find ways to generate value (that we may have overlooked)?”, “Can you work with other people?”. Many people can prepare for, and pass, the ‘typical developer interview.’ That one with the whiteboard, and the typical questions that you never encounter in real life. However, what everyone, on both sides, hopes for is to meet someone who can work well beyond ‘the standard.’ What separates you from the rest is a substantial portfolio project. Not that many people can display the creativity and grit to get a killer portfolio project off the ground.

Because this post is about how to pick an ML project, you have to make a decision: you need to focus on machine learning (ML) or on data management to start your career. The second option is plenty lucrative and doesn’t require you to know much ML. But then you will be stuck with the dreaded ‘data cleaning’ (A data scientist spends 80% of her time cleaning data, and 20% of her time bitching about cleaning data). You may realize that after working extra-hard to become competent in machine learning, you are not doing all that much of it once you get a job.

There’s a trick to avoid too much data cleaning: go to a company that has a good team of data engineers. These are rare, though. So it’s safe to assume that in a ‘normal’ company you will have to do some data cleaning, even if you want to stay away from it. I have more to say about companies; the last bit of this post will cover how to choose which companies to apply for. But now let’s focus on the project.

How do you pick a good project? (Proof Of Concept)

Morten T. Hansen’s book ‘great at work’ shows that exceptional performers tend to ‘Do less, then obsess.’ He shows pretty convincing empirical evidence. So I’m going to recommend: Do one project, not many that are half-assed. If the hiring manager looks at your GitHub, there must be a clear ‘wow’ story there. Something she still remembers after an entire day looking at resumes.

You want to have something to show that is a Proof of Concept (POC). While you will not have resources to build an entire product, your GitHub should have something that demonstrates that such product is feasible. The interviewer must think, ‘ok, if he came to my company and did something like this, he would be adding serious value.’

Good problem

Picking the right problem is a great skill, and it takes years of practice to do it reliably. It’s a mixture of ‘Fermi-style’ estimations (‘how many piano tuners there are in a city?’) time management, and general technical know-how.

The good news is that in ML there’s lots of low hanging fruit. There’s lots of code already, so many pretrained networks, .and so few solved-with-ML problems! No matter how many papers per year we get (too many to track even in a reduced domain), there’s plenty of opportunity in ML right now. Applications of technology this complex have never been more accessible! If you want to practice this skill, tweet 2-3 project-worthy problems a day, and ask people for feedback. If you tweet them at me (@quesada), I’ll do my best to rate them with a boolean for plausibility (in case lots of people take up this suggestion!)

We data scientists have the luxury to pick problems. And you should practice that skill! Knowing what is possible today is the first step. Twitter is a great place to pick up what’s happening in ML. You must have heard of most of the breakthroughs, and have an internal ranking of methods and applications. For example, everybody seems to have watched David Ha’s ‘Everybody dances’ demo. If you didn’t, stop what you are doing and watch it now. Your immediate reaction should be: ‘how can I apply this in a way that generates business value?’

Over a year, at least a couple of dozen papers make a big splash in the scene. Your job is to keep a catalog and match it to business problems. Medium has several writers that are amazing at implementing the latest algos fast. If you want the most exhaustive collection of implementations, try To navigate arXiV, try (this is good to pick up trends, I don’t recommend you to make paper reading a priority if you want to be a practitioner.) About videos: has now videos for most talks. ‘Processing’ NeurIPS is a serious job, so it’s easier to read summaries from people soon after they attended. Remember, you are doing this to pick up “what’s possible,” not to become a learned scholar. It’s tempting to get lost in the rabbit hole of awesomeness.

Which problem you pick says a lot about your maturity as a data scientist and your creativity. You are demonstrating your taste and your business acumen. Passion projects are ok if your passion is not too obscure (for example, I wouldn’t work on detecting fake Cohiba cigars, no matter how passionate you are about those). If knowing the domain can give you an unfair advantage, by all means, use it. A good idea gets people saying ‘I would use that’ or ‘How can I help?’ If you don’t get these reactions, keep looking.

Deep learning (DL) has two good advantages over ‘classical’ machine learning: 1/ it can use unstructured data (images, audio, text) which is both flashier and more abundant than tabular data, and 2/ You can use pretrained networks! If there’s a pretrained network that does something remotely similar to what you want to do, you have just saved yourself a lot of time. Because of transfer learning and lots of pretrained networks, demonstrating value should be easy. Note that taking what you build to production would be problematic if you depend on GPUs, but this is beyond the scope of your proof of concept. Just be prepared to defend your choices in an interview.

If you don’t want to do DL, there’s another useful trick: pick a topic companies care about. For example, If you want to impress companies in the EU, you can do a POC that uses the company’s proprietary datasets while protecting privacy. Impossible, until recently: Andrew Trask is building a great framework to train models in data you cannot access at once. His book ‘Grokking deep learning’ (great stuff!) has an entire chapter on privacy, secure aggregation and homomorphic encryption. The keyword you want is ‘federated learning.’ Google is doing quite a bit of research about it because it could save the company from a frontal attach coming from regulators.

How long should you work on a ‘good problem’? At least 1.5 months. This length seems to work fine at the companies I work for. Anything shorter can look like a ‘weekend project’; you want to avoid that at all costs.


Rather than having one of the popular datasets, for example, ‘mammograms,’ or worse ‘Titanic,’ pick some original data and problem. Remember you are trying to impress a hiring manager that sees hundreds of CVs and many have the same old datasets. For example, MOOCs and bootcamps that ask everybody to do a project on the same topic produce reams of CVs that all look the same. Now imagine you are the hiring manager, and you have seen dozens in the last month; will you be impressed?

You are going to do all that alone (or in a small team of two). In a company, accepting a project is something that goes through a more substantial group:

  • Product defines the problem and creates a user story that describes the need.
  • The research team reads relevant articles and looks for similar problems which other data science teams have faced.
  • The data team collects relevant data, and someone (internal or external) needs to label it.
  • The team tries some algorithms and approaches and returns with some kind of baseline.

Because you are working on a project to showcase your skills, you would have to do this without a large team. But is it impossible? No. Here are some examples:

Malaria Microscope

Malaria kills about 400k people per year, mostly children. It’s curable, but detecting it is not trivial, and it happens in parts of the world where hospitals and doctors are not very accessible. Malaria parasites are quite big and a simple microscope can show them; the standard diagnostic method involves a doctor counting them.

It turns out you can attach a USB microscope to a mobile phone, and run DL code on the phone that counts parasites with accuracy comparable to a human. Eduardo Peire, DSR alumni, started with a pubic Malaria dataset. While small, this was enough to demonstrate value to people, and his crowdfunding campaign got him enough funds to fly to the Amazon and collect more samples. This is a story for another day; you can follow their progress here:

Wheelchair helper

Information about pedestrian road surface type and its roughness are essential for vehicles that need smoothness to operate. Especially for wheelchair users, scooters, or bicycle riders, road surface roughness significantly affects the comfortability of the riding. A large number of street images are available on the web, but for the pedestrian road, they typically do not have roughness information or surface labels.

Masanori Kanazu and Dmitry Efimenko classify road surface type and predict roughness value using only a smartphone camera image. They mount a smartphone to a wheeled device and record video and accelerometer data simultaneously. From the accelerometer data, they calculate a roughness index and train a classifier to predict the roughness of the road and surface type.

Their system can be utilized to annotate crowdsourcing street maps like OpenStreetMap with roughness values and surface types. Also, their approach demonstrates that one can map the road surface with an off-the-shelf device such as a smartphone camera and accelerometer.

These two projects are original. They demonstrate what a small team can do with modern DL and … well, cheap sensors that already come with a phone or you can buy online. If I were a hiring manager, these projects would make me pay attention.


A project can be original, but useless. Example; translate Klingon to Dothraki language (Languages used on TV series that don’t exist in reality). You may laugh, but after > 165 projects I’ve mentored, I’ve seen people generating ideas that fail to meet the relevant criterion.

How do you know what is relevant?

If you are part of an industry, you should know of pain points. What is something trivial that looks automatable? What is something everyone in your sector loves to complain about?

Imagine you are not part of any industry; If you have a hobby, you can do a portfolio project on it IF:
1/ It’s damn interesting and memorable even if way outside the range of interest of the industry. Example: “recommender system for draft beer.” Many people will pay attention to beer.

2/ It showcases your skills: You found or created an exceptionally good dataset. You integrated multiple data sources. You made something that on first thought, most people wouldn’t believe it’s possible. You showed serious technical chops.

Good data

You may complain that there’s not that much data available out there, or that the massive, nice datasets are all inside companies.

The good news is that you don’t need big data to deliver value with ML! No matter how much hype there’s around the importance of large datasets. Take it from Andrew Ng:

Ok, so where do you get data?
Generate it yourself (see previous examples; they both generated their own data; or begged anyone who had data to contribute it (hospitals that deal with infectious diseases for the Malaria microscope).

Some hiring managers may not care much about how you fitted which model; they have seen it before. But if the dataset you generated or found is new to them, that may impress them.

Clean code

Have a clean project on GitHub, something the interviewer can run on his computer. If you are lucky enough to be dealing with an interviewer who checks code, the last thing you want is to disappoint her with something that is hard to run or doesn’t run at all.

Most people have ‘academic quality’ code on their GitHubs, i.e., something that works just enough to get you a plot. It’s damn hard to replicate, even putting in some effort (something a hiring manager will not do).

If you have clean code, it will feel refreshing. A good readme, appropriate comments, modules in python, good commit messages, a requirements.txt file, and … a simple way to replicate your results, such as ‘python’ That’s all it takes to be above 90% of the code most people learning data science have on their GitHub. If you can defend your library or model choices in an interview, that’s moving you up the ranking too.

Apply Now

Do not obsess with performance

I call this the “Kaggle Mirage.” You have seen Kagglers making real money and raking in the prestige just by moving a decimal point. Then you may think “I need to get to 90% accuracy because my manager (not a data scientist) set it as a goal.” Don’t let that happen to you without asking some important questions. What would happen if you only got to 85%? Are there nonalgorithmic ways to compensate for the missing 5%? What is the baseline? What is the algorithm? What is the current accuracy? Is 90% a reasonable goal? Is it worth the effort if it’s significantly harder than getting to 85%?

In all but a few real projects, moving performance a decimal point may not bring that much business value.

Now, if you have been working on a problem for a week and performance didn’t change… is it time to stop? Maybe your peers on a standup notice the pattern and are encouraging you to drop that project and join another one (coincidentally, theirs). Expectation management for data scientists would be a great post.

In data science, progress is not linear. That is you could spend days working on something that doesn’t move the needle, and then, one day, ‘boom,’ you have gained 5 points in accuracy. Companies not used to work with data science will have a hard time to understand that.

I recommend not to do Kaggle (or not only!) if your goal is to build a portfolio project to get hired.

Deciding whether to apply and preparing for an interview

Even if you do have a great project to show off, you still have to (1) find good companies to apply to, and (2) prepare. I estimate about 10% of companies are a slam dunk: They have a team that writes blog posts, they are using reasonable algos for their problems, they have a good team already, and AI is a core component of their product. Startups with funding and big N companies land in this box. For the remaining 90% of companies, it’s far harder to estimate whether they are a good match for someone building an AI career. I have quite a few heuristics, but this is worth a different post.

What doesn’t discriminate excellent and bad AI-career-building companies? The job ad.

It is difficult to write up a job description for a data scientist role; more so if there isn’t already a DS team in the company to write it! Even when there is one, HR could have mangled the job ad by adding criteria.

As a candidate, you can use this rule of thumb: ignore requirements and apply; If you only have 50% of the bullet points, that might be better than most other applicants. Knowing this would add some companies to your list, ones in which you could have disqualified yourself.

When companies don’t have an easy way to tell if a candidate is any good, they revert to ‘correlates’: pedigree, paper certifications, titles. Terrible choice, because so many great data scientists today are self-taught. Those companies asking for a Ph.D. or Masters are missing out on great talent that cut their teeth on and Kaggle.

Before you start carpet bombing LinkedIn, … Have you prepared for interviews? Because it’s not a walk in the park! Don’t try to go interviewing without preparing; your competitors will.

The standard software developer interview in the Valley takes about three months of preparation. If you don’t believe me, go to this Reddit. That goes equally for fresh CS graduates (who should still remember all those ‘algorithms and data structures’ classes) and for more senior people (who have all the rights in the world to have forgotten them).

In less competitive places, it may not be that important to know all these CS tricks. In fact, preparing for a DS and CS interview at the same time may be overkill. Some positions (machine learning engineer) may require you to be a senior engineer on top of knowing machine learning.

For data science positions today, you don’t necessarily need to prepare ‘algorithms and data structures’ questions. But the trend is that companies ask for more and more engineering from their data scientists. You can know in advance by checking the profiles of company data scientists in LinkedIn. Are they very engineer-y? Then get the book ‘cracking the coding interview,’ and do a few exercises.


Work on one project. Spend 1.5 months on it. Make sure it’s impressive to a hiring manager that sees hundreds of CVs for each position. Make sure you pick a ‘good problem’, one that is, original, relevant, and uses good data.

Make sure you produce clean code, pick decent companies before you mass-apply, and prepare for interviews.

Apply Now

Training your empathy as a cure for cofounder problems, the #1 startup killer

I’m Jose; I run Data Science Retreat, a 3-month school that takes pretty advanced machine learners and gets them to work together with mentors to produce a killer deep learning portfolio project. We want these projects to have social impact (example: a malaria microscope).

I’ve been doing startups for 10 years. I’m a solo founder now, and successful (bootstrapped two companies). I was miserable when I cofounded. I’ve experienced my share of hard conversations, cofounders leaving, jealousy, bickering for equity, etc. I’m happy to risk a drop in happiness cofounding pagain because I want to do the most good I can, and cofounders are the surest way of scaling impact.

I’m still scared of having cofounders, a single point of failure in your life. Or I was! I think I’ve found a hack that makes me feel confident that I will deal with any disagreement in a non-stressful way.

In this post, I’ll tell you about ‘Non-Violent communication’ (NVC), a technique that makes you better at ’empathy.’ This is what I did, warts and all. It may, or may not work for you. It’s not a surefire solution, but it is a beautiful hack, and I’m ecstatic to see if it works for anyone else.

The hack

How could I prevent any stress that comes from human interactions in a startup? It feels like an impossible task. But I’ve been here before (we all have!): a task that feels impossible blown wide open by a simple, elegant solution. The true definition of a hack. Last time I can remember finding a hack this powerful was when I was suffering from RSI. I thought my career in front of a keyboard was over. A horrible thought. Nothing standard medicine knew worked. Then, I found a solution (that may deserve a different post, ‘how a tennis ball in a socket saved my career’).

This book: The Trigger Point Therapy Workbook (Clair and Amber Davis) was enough to help me understand the way out. There are trigger points, and you have the ability to massage yourself. You know better where it hurts. Boom. Solved problem.

When you find something that effective (and rare), you want to tell others. This is exactly why I’m writing now. I’ve found another hack that is as effective, solving a problem as large (or larger!). You can train your empathy, and have better relationships with everyone around you. Including difficult people. Including cofounders (non-overlapping sets, with any luck).

It’s all in a single book, Marshall Rosenberg’s ‘Non-Violent communication,’ aka NVC.

What is empathy?

Empathy is hard to define. For me, it’s about

1- Being present, in the moment

2- Deep curiosity for what’s going on in the other person’s life

Empathy is a language. The components are simple (like a grammar), but the implementation is not. It takes lots of practice to learn a new language, and this is also true for empathy, at least the NVC variety.

Empathy is not compassion. You can have compassion for a group of people on a different continent who are suffering. Empathy happens one on one, with a person in close proximity. This is my definition, and I’m not an expert. Fortunately, there’s a much better definition of this language that is extremely actionable: NVC. This is how it works.

Empathy, the NVC way

Rosenberg’s method is simple and elegant, like lisp. it has the beauty of internal consistency.

An empathic conversation should go through four steps: observation, feeling, need, and request. On this post, I’m going to use a simpler version without the request at the end.


Just observe what the other person is doing that is causing you trouble, and state it. Do not provide evaluation. Otherwise, it feels like a judgment. Avoid judging people at all costs. Judging and blaming has become second nature in our culture, and you can see how it’s extremely toxic. You get intuitively that judging is bad, yet we do it all the time.


‘I have noticed that you haven’t  been able to work very long the last two days because you went to a festival.’

When we judge others, we contribute to violence. Intellectual analysis is often received as criticism. Stop the urge of providing it. The ‘because’ part may be already too much.

Rosenberg has a really nice rule. Do not use ‘but.’ “Rather than putting your ‘but’ in the face of an angry person, empathize.”


Express your feelings. This is hard; some cultures make it harder than needed. There’s only about a hundred emotion words, make sure you use one of these. Many sentences using ‘I feel’ are not about emotions at all. You can use simple words, like ‘sad,’ ‘angry,’ ‘disappointed.’ No need for poetry here.


‘I feel disappointed because I’m working harder than you.’

Make it clear to the other person how you feel, but don’t make her responsible for your feelings. Only you are.

Rosenberg says ‘speak your pain nakedly without blame.’ Nobody said NVC is easy.

That should be enough for this step; outside an NVC convo, take a guess on someone else’s feelings, and tell them to see if you are right. Many people work hard hiding their feelings and may feel exposed an uncomfortable talking about them. Others will feel elated and impressed that you nailed them. Learn to identify feelings from the stream of communications that goes around you.


Express your need. What can is ‘alive’ in you that the other person could satisfy? Note that needs create emotions. The other person doesn’t create the feeling, you do (through your needs). The other person may not be aware of your needs if you never communicated them. Rosenberg says ‘If we express our needs, we have a better chance of getting them.’ So simple, so true, so uncommon.


“I need to feel reassured that we are both totally committed to the success of our company.”

Unlike feelings, needs come in all forms; there is no shortlist. This one is a need to feel something. it could also be something more mundane, like a need for cleanliness (together with a request that you do the dishes).

Most people never communicate their needs. Clearly, they ask you to infer them. This is ineffective, don’t be that person.

In the example, you were the one communicating a need. But you could be the listener. Stay in the moment, no matter how uncomfortable the silence may be, no matter how much the other person is struggling, till she has been heard.

You will ‘see’ it when they felt heard: there’s a body change, shoulder drop, maybe a sigh, the flow of words stops. The conversation tone changes. You feel closer.

Don’t worry about the last part, the request. If you manage to see that body change you are already on your way to an agreement. Just make sure that your request is not a demand, is actionable, and worded in positive terms (i.e., don’t use ‘not’).

The more we hear them, the more they’ll hear us.

‘Ok, but does it work at all? Does it work for my particular conflict, at least?’ you may be thinking.

The challenge

I read voraciously, so I consumed all of Rosenberg’s books. I tried it with my six-year-old son and my girlfriend, to different degrees of success.

Son: crying because his football cards felt and are out of order

Me: Are you crying because you have a need for order and the cards are on the floor?

Son: nods, feeling heard. Crying stops in a too-good-to-be-true way

One other story:

Me: (some request). To make sure you understood, could you repeat what I said to me? (part of the method)

Girlfriend: Are you running this NVC thing on me? (Angry)

You can see it didn’t really work on the second story. This was a bad experience I didn’t want to repeat. As much as I had read about it, I was not any good at NVC. I was still not any better at empathy.

People write a lot about how NVC in the hands of a newbie sounds robotic as hell as not at all like receiving empathy. This robotic delivery may backfire. There are variants, for example, ‘street NVC’ that make it more informal. But the point is that you need to be present and curious about the other person. No scaffolding can turn a dull, uninspiring conversation into an emphatic one. Don’t try to give empathy if you don’t really care about the other person.

The practice

So how do you get out of ‘robotic NVC’? Practice. The best way I’ve found is to get together with others who are also trying to get better. A meetup is ideal. In Berlin, where I live, there was none, so I created one. Meeting at the DSR office, which makes for fascinating contrast (people door to door discussing hardcore algorithms for deep learning vs. people practicing empathy).

There are lots of meetups all over, but if there’s none where you live, I suggest you start one. It was extremely beneficial for me, even on my tight schedule.

NVC works excellent in ‘pair programming’ mode: one person is the one who receives empathy, one gives empathy (the one with hands in the keyboard so to say), and one observes and gives hints. Then you rotate.

It’s not impossible to practice NVC while alone. Self-empathy is a thing. We are terribly judgmental with ourselves (self-criticisms). For example, try to avoid the word ‘should’ (to yourself or two others). This word has enormous power to create blame. “Don’t do anything that isn’t play” says Rosenberg.

What else can you practice alone?

1- Observation. Practice translating judgment into something neutral.

2- Connect your feeling with your need: “I feel… because I need …”

3- Saying thank you in NVC: “This is what you did; this is how I felt; this is the need of mine that was fulfilled.” Compliments are not great. They are actually judgments, positive ones but judgments. It’s much better to know how you enriched the life of the person praising you so that you can do more of it.

4 – Monitor how you talk, stop yourself if you are using judgments, ‘buts’ or ‘shoulds.’ “From the moment people begin talking about what they need rather than what’s wrong with one another, the possibility of finding ways to meet everybody’s needs is greatly increased,” says Rosenberg.

So, to answer the ‘does it work’ question… I’m a total beginner. I can tell you they are not kidding when they say NVC is like a language.

I need to practice more.

Have I experienced any benefits? I became Vegan around the same time I started learning NVC. That may mean I’m improving my health. I have a much deeper appreciation of who my outstanding girlfriend is; I ‘see’ her in ways that I didn’t before. I truly love this woman. I became involved with the ‘effective altruism’ movement. I constantly think about what is violent and how we can remove violence from our communication. I come up with better ideas to use deep learning for social impact. I feel more connected to the world around me. I meet more people by chance that are in the same mental space (the DSR scholarships we ran are an example).

But to the point: do I feel capable of starting something with cofounders? Yes, for the first time in many years. I’m confident any difficult conversation will be solved, even with my primitive empathy training.

NVC feels as effective as that tennis ball in a socket that saved my career once.