A Student's Guide to Preparing for Data Science Interviews

http://www.acheronanalytics.com/acheron-blog/how-to-prepare-for-a-data-science-interview

by rogocopH • 9 years ago

129 59 9 years ago

bllguo3• 9 years ago

Unfortunately there is very little here that isn't just general interview advice.

As a new grad that went through the hunt very recently - it was a messy process. Very few places will consider you without extensive experience, or a masters/Ph.D. Of course if you're hiring people to research machine learning algorithms that's justifiable, but plenty of the responsibilities people associate with data scientists don't require advanced degrees.

And the number of posts asking for 5, 7, even 10 years of experience... absolutely astounding.

As someone uninterested in going back to school, I've resigned myself to getting some work experience and doing personal projects for 1-2 yrs before trying again.

kinkrtyavimoodh• 9 years ago

Most of these listings have over-inflated experience requirements. A lot of them will entertain you even if you have half the experience they ask for.

bllguo3• 9 years ago

Good to know. As a new grad I couldn't really claim to have any experience, so that wouldn't have helped me. I was just commenting that these requirements were absurd, considering that the pool of people meeting them would be so small.

Definitely will take note of that in the future though.

autokad• 9 years ago

I recently graduated from University of Pennsylvania with a masters in computer science after 9 years experience as a DBA and GIS, + 1 year experience working for a social media lab doing natural language processing (co authored on several papers) + 1 year experience working with big data (10 tb in size).

applied to ~85 data science positions. I can't even get recruiters to call me for a phone screening, so don't feel down =)

spoopy01• 9 years ago

Unfortunately most people posting data science jobs don't really have good priors on the necessary qualifications for those positions. As someone who has gotten multiple data science positions in startups and larger enterprises, I highly recommend applying to data science jobs through platforms like AngelList, which allow you to speak to employers directly and circumvent many of the bureaucratic processes that tend to discourage people from applying to jobs they are actually well qualified for.

mindcrime2• 9 years ago

spoopy01 nailed it. Most of the people hiring data scientists don't really know what data science is, or probably even why they need it. So they inflate the hell out of the requirements to a. CYA and b. hopefully get somebody so experienced they can come in and make up for the lack of organizational understanding of data science. IOW, they want somebody who can "teach us what we don't know".

softawre• 9 years ago

Teaching me what I don't know is what I want with all of my engineering hires. I want people better than me who will tell me why my architecture isn't ideal or whatever the case is.

huac• 9 years ago

I just graduated undergrad as well. The biggest factors assisting me in getting a DS position were:

1. Previous internship in data science 2. Experience developing R packages and putting them on GitHub 3. Really having statistical theory down pat

You don't need an advanced degree to be a data scientist but you need a strong understanding of stats and how to work with data. Having an advanced degree is a good indicator that you can do that. But it's not a prerequisite for an undergrad: Github, internships, TA-ships can make that up.

I think one advantage is that while PhD's are typically very good at the research process and the techniques used in their research, undergrads could be more flexible and adaptive to different situations.

minimaxir5• 9 years ago

So I've been interviewing for data analyst/science positions since leaving Apple in April.

I may do a postmortem on my search later, but speaking from my experience with many, many interviews over the past couple months, the TL;DR is that the conventional interview wisdom on Hacker News/the cscareerquestions subreddit/this article is wrong and out of date. Interviews for such positions require a different set of skills than just reading Cracking the Code Interview (and ones that you can't get at a data bootcamp).

cbcoutinho• 9 years ago

If you had to summarize into three points?

minimaxir5• 9 years ago

I have one notable observation:

On Hacker News, every time an interview thread pops up, there is a discussion decrying the use of technical screenings before an onsite, and often suggest practical work experience instead using a homework assignment (which this article does not discuss).

Most of the companies I've talked with for data analyst/science roles have given me both a homework assignment and a technical screen before the onsite. And often a prescreen test before both of them.

There have been a number of occasions where I easily passed the homework screen but failed the technical screen (without any feedback as to why). And it's beginning to get annoying.

alexchantavy• 9 years ago

What kinds of technical questions do they ask in a data science interview?

minimaxir5• 9 years ago

On the stats side, often higher-level theory questions, such as "How does the k-means algorithm work?", "How do you select the best k for k-means?", "What is the curse of dimensionality?" which again would not be things covered at a data boot camp or data science thought pieces on Medium.

On the technical side, there is often more-advanced SQL (nested JOINs + PostgreSQL window functions). On the big data side, there is often discussion of distributed systems (e.g. Spark clusters) and practical algorithmic complexity at scale (i.e. instant fail if you suggest anything loglinear or slower).

AlexCoventry• 9 years ago

Hi, minimaxir. If confidentiality doesn't prohibit it, I'd be curious to know what the most interesting roles you interviewed for were.

booleandilemma• 9 years ago

How many data scientist jobs are actually out there? I can understand data scientist being a position at one of the big 5 tech companies, but are they really in demand elsewhere?

I've never actually met someone off the internet who calls themselves a data scientist.

likelynew• 9 years ago

And in some consultancies too.

bllguo3• 9 years ago

Well, there's a job post on HN right now looking for data scientists :)

tomrod• 9 years ago

We exist. I just presented at a firmwide Data Science Forum for a very large financial firm.

gipp2• 9 years ago

Ad-tech, fin-tech, marketing analytics firms all hire data scientists in huge numbers. Media companies as well, increasingly. This is probably NYC-biased.

ellisv• 9 years ago

I've never actually met someone off the internet who calls themselves a data scientist.

You could probably say the same about a lot of job titles. I've never meet a sanitation worker but my trash gets picked up once a week nonetheless.

tegansnyder• 9 years ago

Manufacturing, finance, areospace, automotive industry, and medical industry are a few other places hiring data scientists.

reader50008• 9 years ago

Technically anybody who uses Excel is a "data scientist". Just got to get the right buzzwords.

achompas7• 9 years ago

This is absurd and false. This person is an analyst of some sort.

Maybe this holds in the consulting world? It definitely does not hold in the tech world, IME.

hellogoodbyeeee• 9 years ago

I think the field is seeing a large amount of "title bloat". I've seen job postings for data scientist roles that are only looking for SQL and Microsoft Excel skills. I almost accepted a data scientist role at a small manufacturing company, but a more realistic job title would have been "Marketing Analyst"

mmierz3• 9 years ago

I think it's a dumb name for what I do so I call myself a programmer if anyone asks.

mcrad• 9 years ago

Analyzing the Analyzers, free eBook. Assuming the student is sharp on technical skills, this look at the human side could be helpful to prepare. https://www.amazon.com/Analyzing-Analyzers-Introspective-Sur...

reader50008• 9 years ago

"Data science" is a field with so much conceptual churn and fads that interviewing for it is a completely ridiculous notion.

denzil_correa• 9 years ago

The thing is : Data Science requires ... "scientific" rigor and thought process. A lot of people who hire often forget that science is integral to data science: it's right there in the name.

rogocopH• 9 years ago

I think this was posted earlier. But some companies really just want a statistician.

Very few companies are actually using their data scientists as scientists. From my experience.Except for when I worked at a large hospital. We had a research board, and had to be certified to study Humans CITI. But beyond that..

gaius4• 9 years ago

But some companies really just want a statistician

In what way is what statisticians do not "scientific"? Setting up and rejecting (or not) the null hypothesis is the very definition of the scientific process...

A Student's Guide to Preparing for Data Science Interviews

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