SQL, stats, and the analytical thinking that separates good analysts from great ones. Every question is the kind of problem you would actually face in an interview.
Interview preparation guide
The quiz above is a quick way to check your knowledge. Before the interview, prepare a specific example for each of these themes: SQL, Statistics, Data Visualisation, Problem Solving. Practise saying your answer aloud, then refine the detail, evidence and outcome rather than memorising a script.
Question 1 · Analytical Decomposition
Decomposition (a "metric tree") is the most systematic approach. It turns a vague question into specific, testable hypotheses. Interviewers want structured thinking, not just a chart.
Question 2 · SQL Fundamentals
WHERE filters individual rows before GROUP BY runs. HAVING filters the aggregated results after GROUP BY. This is one of the most commonly tested SQL concepts in interviews.
Question 3 · Experiment Design
A/B testing isolates the feature's impact from other variables like seasonality and marketing. Before/after comparisons are confounded by external factors. Surveys measure sentiment, not behaviour.
Question 4 · Statistical Interpretation
A p-value is the probability of observing the result (or more extreme) if the null hypothesis of no effect were true. A p-value of 0.03 means a 3% chance of seeing this difference by chance alone.
Question 5 · Data Visualisation
Histograms show the shape of a distribution (normal, skewed, bimodal); box plots summarise it with quartiles. Pie charts show proportions of a whole; line charts show trends over time.
Use the quiz to identify the theme you need to improve, then rehearse it as a spoken answer and get feedback on your structure, pace and specificity.