Statistician interview questions: 22 to prepare for

1. Walk me through a recent project where you used SQL. What did you do yourself?

   19% of today’s 42 open statistician postings name SQL.

   A good answer shows: Your own hands-on part, the choices you made and a number for the result.

   Sample answer: “In my last role I found a pricing error with a check in SQL that had cost about $18K a month; it was fixed within the week. I did that part myself: I chose how to do it, checked the result and explained it to the team.” Then say what you would do differently.

2. What is a mistake people often make with Agile, and how do you avoid it?

   7% of today’s 42 open statistician postings name Agile.

   A good answer shows: That you have used it long enough to know where it goes wrong.

   Sample answer: “In my last role I built a revenue dashboard in Tableau used by 40 people each week; monthly reporting went from 3 days to 4 hours. I did that part myself: I chose how to do it, checked the result and explained it to the team.” Then say what you would do differently.

1. What does len([4, 8, 15]) return?

   A Python question (40% of today’s postings name Python). More in the Python skill test.

   Answer: 3. len counts the items in a list: there are three.

2. Which of these is a dictionary?

   A Python question (40% of today’s postings name Python). More in the Python skill test.

   Answer: {"a": 1, "b": 2}. A dictionary stores pairs of a key and a value, written with curly brackets and colons. {1, 2, 3} is a set.

3. What is the difference between a list and a tuple?

   A Python question (40% of today’s postings name Python). More in the Python skill test.

   Answer: A list can be changed after it is made, a tuple cannot. Lists are mutable (changeable); tuples are immutable.

4. What does this print? for i in range(3): print(i)

   A Python question (40% of today’s postings name Python). More in the Python skill test.

   Answer: 0 1 2. range(3) counts from 0 up to, but not including, 3.

5. Which clause keeps only the rows that meet a condition before any grouping happens?

   A SQL question (19% of today’s postings name SQL). More in the SQL skill test.

   Answer: WHERE. WHERE filters rows first. HAVING filters groups after GROUP BY.

6. What does an INNER JOIN between customers and orders return?

   A SQL question (19% of today’s postings name SQL). More in the SQL skill test.

   Answer: Only customers that have at least one matching order. An inner join keeps pairs that match on both sides. A LEFT JOIN is the one that keeps customers without orders.

7. You need the number of orders for each customer. Which query does it?

   A SQL question (19% of today’s postings name SQL). More in the SQL skill test.

   Answer: SELECT customer_id, COUNT(*) FROM orders GROUP BY customer_id. GROUP BY makes one row per customer, and COUNT(*) counts the rows inside each group.

8. What is the result of comparing a value with NULL using = (for example, price = NULL)?

   A SQL question (19% of today’s postings name SQL). More in the SQL skill test.

   Answer: Unknown, so the row is never returned. NULL means “no known value”. Any comparison with = gives unknown. Write IS NULL to find empty values.

Too few statistician postings have a full description to count on their own, so these shares are from all 26,041 postings with one.

1. Tell me about something you owned from the first idea to the result.

   44% of all 26,041 open postings with a full description ask for ownership or end-to-end work.

   A good answer shows: That you saw it through when it got hard, with a number for the result.

2. Tell me about a time a rule or regulation slowed your work down. What did you do?

   40% of all 26,041 open postings with a full description mention compliance or regulation.

   A good answer shows: That you followed it and still delivered, not that you went around it.

3. Tell me about a time you had to win over people outside your team who disagreed with you.

   33% of all 26,041 open postings with a full description mention stakeholders.

   A good answer shows: Who they were, what each side wanted, what you did to reach agreement and how it ended.

4. Describe a project you delivered with people from other teams. What was your part?

   27% of all 26,041 open postings with a full description ask for work across teams.

   A good answer shows: Your own part, how you kept the teams in step and the result.

5. Tell me about a time plans changed at short notice. How did you adjust?

   24% of all 26,041 open postings with a full description describe a fast-paced place.

   A good answer shows: A quick new plan, what you dropped on purpose and how you kept others informed.

6. How much are you able to travel for work?

   24% of all 26,041 open postings with a full description mention travel.

   A good answer shows: An honest number of days or share of time, so there are no surprises after the offer.

1. Tell me about yourself.

   Almost every interview opens with it.

   A good answer shows: Under a minute: your current work as a statistician, one result with a number and why this job is the next step. Not your whole resume.

2. Why do you want to work here?

   It tests whether you read about the company.

   A good answer shows: Something specific: a product, a goal from the posting or a problem you can help with.

3. Why are you leaving your current job?

   It checks for problems you might bring along.

   A good answer shows: What you are moving towards, said briefly, with no criticism of your employer.

4. What are your salary expectations?

   62% of today’s statistician postings state pay; know where you stand in the range.

   A good answer shows: A range you can defend. Today’s 26 statistician postings that state a yearly US-dollar range advertise a median of $204K; the middle half $177K to $239K. Ask for their range first if you can.

5. What is one of your weaknesses?

   A classic, still asked.

   A good answer shows: A real weakness that does not block this job, and what you do about it.

6. Do you have any questions for us?

   The last question of almost every interview.

   A good answer shows: Two or three questions you prepared; the list below has some.

What would make someone in this role successful in the first six months?

It shows you think about results, and the answer tells you what the job really is.

Why is this role open?

A new role, growth or someone leaving: each tells you something different.

Which countries and time zones can this role be done from?

43% of today’s statistician postings are remote, and many of them still limit the countries.

How will my work be measured, and how often will we review it?

You learn what matters to your manager before you start.

What are the next steps, and when will you decide?

You know when to follow up, and you can plan around other offers.

What questions are asked in a statistician interview?

Questions about the skills the postings name (SQL, Agile), about how you work (end-to-end ownership, compliance and regulation, stakeholders) and the questions almost every interview has, such as “Tell me about yourself” and your salary expectations.

How should I answer statistician interview questions?

With a real example: the situation, what you had to do, what you did yourself and the result, with a number. This is the STAR method; aim for 60 to 90 seconds an answer.

How do I prepare for a statistician interview?

Prepare three real stories with a number each (a result, a problem you solved, work with other people), practise them out loud for 60 to 90 seconds, and revise the skills the postings name most: SQL, Agile. Read the posting again the day before: the duties it lists are what they will ask about.

Is a statistician interview hard?

It depends on the level: today’s statistician postings ask for 7 years of experience at the median. Most interviews mix questions about the skills in the posting with questions about how you work; the technical part is easier with a real example ready for each skill.

What salary should I ask for as a statistician?

Today’s 26 statistician postings that state a yearly US-dollar range advertise a median of $204K. Adjust for your experience and the country, and ask for their range first.