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Fred Hutch Cancer Center Data Scientist Interview Questions & Guide 2026

Data scientist interview prep for Fred Hutch Cancer Center: original practice on experiment design, SQL and metric reasoning, with worked solutions.

The 60-second brief

A Data Scientist at Fred Hutch Cancer Center plays a critical role in bridging the gap between complex biological data and life-saving clinical breakthroughs. Operating at the intersection of computational biology, biostatistics, and oncology, you will translate massive, high-dimensional datasets into actionable insights that directly impact cancer treatment, prevention, and research. Your work will support world-class principal investigators, clinicians, and laboratory scientists who rely on rigorous data analysis to design clinical trials, discover therapeutic targets, and understand the molecular mechanisms of disease.

Seniority shifts the scope more than the words in the title do. Earlier-career loops mostly check that you execute a well-posed analysis correctly; senior loops check that you can decide which question is worth answering and defend what you chose not to do.

Focus areas

  • Reconstruct drug exposure intervals from dispensing records
  • Separate censoring from events in time-to-event models
  • Build member-month denominators from overlapping coverage spans

Overview

At Fred Hutch Cancer Center, the data environment is highly sophisticated and diverse. You will work with genomics, proteomics, electronic health records (EHR), and clinical trial outcomes. This is not a standard corporate data science role; your algorithms, statistical models, and pipeline designs are directly tied to scientific discovery and patient outcomes. The scale and complexity of the biological data require a deep commitment to scientific rigor, reproducible research, and collaborative problem-solving.

To succeed in this role, you must possess both the technical capability to handle messy, heterogeneous scientific data and the communication skills to translate complex statistical findings to non-technical stakeholders. You will join an environment where curiosity, precision, and alignment with the organization's mission to eliminate cancer are highly valued.

The Fred Hutch Cancer Center interview process

Fred Hutch Cancer Center candidates report 3 rounds · ≈ 3-5 weeks. The stages below are what candidates describe, not a published process.

Recruiter Screen

A screening call is a matching exercise run by someone who will not evaluate your statistics. They are checking that the work described on your resume is work you personally did, and that its scope matches the level the role is written for. Logistics get settled in the same half hour so nobody spends an interviewer's afternoon on a mismatch. The answer that fails is the one narrated in the plural. If every sentence is 'we built' and 'the team decided', there is nothing specific to write down about you. Name the piece that was yours, the decision you made inside it, and what changed after.

What to demonstrate

  • Whether the ownership implied by your resume survives one round of follow-up about who actually did which part
  • Whether your described scope (data size, stakeholders, what shipped) matches the seniority the role is written at
  • Whether timeline, location and compensation expectations make the rest of the loop worth scheduling

How to prepare

  • Rewrite your top three resume bullets in the first person singular, each with the decision you made and what moved afterwards, then say them out loud once so the 'we' does not return under pressure
  • Attach one number to each project: the baseline, the change, and the window it was measured over. Where impact was never measured, say that plainly rather than inventing a figure
  • Settle your compensation range before the call and give it as a range with a reason behind it, such as current total comp or a competing timeline, instead of deflecting the question twice

Technical and Behavioral Interview

Most of the weight in this round sits on the disagreement questions. Data work routinely produces an answer someone senior did not want, and the interviewer is trying to learn what you do in that hour. Both failure modes are common: folding as soon as a director pushes back, and treating the pushback as ignorance to be corrected with a better chart. A strong answer usually contains a specific thing the other person knew that you did not, and describes how you found out whether it changed the conclusion.

What to demonstrate

  • Whether you can state the other side's argument accurately before you explain why you disagreed
  • What you treated as evidence during the disagreement, such as a rerun under their assumption or a holdout check, rather than persuasion technique
  • Whether you distinguish being overruled from being wrong, and can give an example of each

How to prepare

  • Write out one disagreement where you turned out to be wrong, and say what in the data misled you. Candidates prepare the story where they were right, and the follow-up asks for the other one.
  • For your main disagreement story, be ready to say what result would have made you drop your position. If no such result exists, you were not arguing from the data.
  • Practise stating the opposing position out loud in one sentence the stakeholder would accept, then continue the story.

Panel Interview

A day of back-to-back interviews samples your floor, not your ceiling. Four hours in, the habits that carry a good answer are the first to go: restating the question before solving it, asking what the data would have to look like, checking a number before quoting it. What the day decides is whether the tired version of you is still someone to leave alone with an ambiguous problem. The round that sinks a candidate is usually not the hardest one. It is the one immediately after the round that went badly.

What to demonstrate

  • Whether the late rounds get the same clarifying questions as the first one, or whether you start answering immediately to save effort
  • Whether a weak answer stays in the room it happened in, instead of following you into the next conversation as apology or distraction
  • Whether the quality of your questions holds up, since fatigue removes curiosity about the problem before it removes knowledge of the method

How to prepare

  • Rehearse the length, not just the content: book four mock interviews of different types in one afternoon with short gaps, because the one you need to observe is the fourth
  • Put the two or three questions you ask at the start of any problem on a card in front of you, so that under fatigue it is a habit you run rather than a decision you make
  • Decide in advance what the gap between rooms is for: water, one line of notes on anything you promised to follow up, and an explicit close on the round that just ended so it does not travel
  • Prepare a different closing question for each interviewer, so the end of a long day does not produce the same one four times

Where candidates lose points

Pre-post evaluation on a high-cost or high-risk cohort

Cohorts selected on an extreme value of the outcome regress toward the mean on their own. Members identified as the top 1 percent of spend in one year spend far less the next, whether or not anyone intervenes, because the selecting year captured both chronic severity and one-off events. A pre-post design on such a cohort will report savings every time. A concurrent comparison group selected by the same rule in the same period, or a regression discontinuity at the selection threshold, is the minimum credible design.

Ignoring clustering by provider, facility, or site

Patients within a provider panel, and subjects within a trial site, are correlated on both case mix and practice pattern. Standard errors computed as if observations were independent are too narrow by roughly the design effect, 1 + (m - 1) * ICC, where m is the average cluster size. With 50 patients per provider and an intracluster correlation of only 0.02, variance is understated by about a factor of two, which manufactures significant provider differences out of noise. Cluster-robust errors or a random intercept per provider, and cluster-level randomisation when you design the test, are the corrections.

Extrapolating a first-week lift inflated by novelty effects

Plot the treatment effect by days since first exposure instead of quoting one pooled average. A lift that decays toward zero across the test window is behaviour that will not persist, and annualising it produces a forecast that misses by an order of magnitude.

Building features from data that postdates the prediction time

Check every feature against the timestamp at which the model would actually score, and drop anything computed from a window that includes or follows the label event. For a forecasting use case, split train and test by time rather than at random, and split by entity when the same entity recurs.

Questions & practice

Can you explain the concept of multiple testing correction (e.g., FDR, Bonferroni) and why it is critical in genomic analyses?

Medium · statistics and probability

Approach

  1. Translate the result into the decision it informs, in one plain sentence.
  2. Say what the estimate is of, and over what population it generalises.
  3. Quantify uncertainty explicitly rather than reporting a point estimate alone.

Follow-up

  • What sample size would you need to detect an effect half this size?
  • Which assumption here is most likely to be violated in practice?

What is the difference between survival analysis methods, and when would you use a Cox proportional hazards model versus a Kaplan-Meier estimator?

Medium · machine learning and modelling

Approach

  1. Set a baseline first, so any model has something honest to beat.
  2. Check what information would not exist at prediction time, and exclude it.
  3. Pick an evaluation metric that matches the cost of each error type, not a default.

Follow-up

  • Where could label leakage enter this setup?
  • What would you monitor after launch to know the model is still valid?

Bootstrap a confidence interval for a ratio-of-sums PMPM

Medium · bootstrap · ratio estimator · resampling unit

You have one row per member for a fully run-out incurred year: member_id, member_months, allowed_amount. Report allowed PMPM, defined as sum(allowed_amount) divided by sum(member_months), with a 95 percent confidence interval from a bootstrap you write yourself. No library resampler. Resample members with replacement, recompute the ratio on each of 2,000 replicates, take a percentile interval, and seed the generator so the result reproduces. In two sentences, state why resampling claim lines instead of members would be wrong.

Approach

  1. Name the estimator precisely: PMPM is a ratio of sums, not the mean of per-member ratios. The two differ whenever exposure correlates with spend, and it does, because members who churn out mid-year are systematically different from members covered all twelve months.
  2. Resample the unit of independence, which is the member, and recompute numerator and denominator together on the same draw. Recomputing only the numerator against a fixed denominator understates variance and is a common slip.
  3. Pull member_months and allowed_amount into numpy arrays once, then draw indices with rng.integers(0, n, size=n) per replicate. Index draws over arrays run one to two orders of magnitude faster than DataFrame.sample, which is the difference between 2,000 replicates and 200.
  4. Take the 2.5th and 97.5th percentiles of the replicate ratios. Expect an interval that is asymmetric around the point estimate, because healthcare spend is right skewed. That asymmetry is the method working, not a bug to centre away.
  5. Answer the line-resampling question concretely: the many lines of one high-cost member are not independent draws, so line resampling shrinks the interval toward zero width, and member_months has no line-level analogue, so the denominator becomes undefined.

Worked solution (25 min)

  1. Compute the point estimate as allowed.sum() / months.sum() on the full sample.
  2. Extract both columns to float numpy arrays and create rng = np.random.default_rng(seed).
  3. Loop 2,000 times: idx = rng.integers(0, n, n); ratio = allowed[idx].sum() / months[idx].sum(); store it.
  4. Take np.percentile(replicates, [2.5, 97.5]) and report the point estimate with that interval and the seed.

Expected result: A point estimate plus a 95 percent percentile interval that is wider on the upper side than the lower. With tens of thousands of members and a typical commercial cost distribution the relative half-width lands on the order of a few percent; an interval a small fraction of a percent wide is the signature of having resampled rows rather than members.

Verify it yourself

  • Re-running with the same seed reproduces both bounds exactly.
  • Raising replicates from 2,000 to 8,000 moves each bound by less than its third significant figure.
  • The mean of the replicate ratios sits close to the point estimate; a large gap indicates a bug in the resampler rather than skew.
  • Replicate denominators cluster tightly around the observed total member-months, which confirms the draw size is n rather than a fixed constant.

Follow-up

  • Half a percent of members have a transplant or a long NICU stay. Does a percentile interval still have nominal coverage, and what would you do about the tail?
  • The question changes to comparing PMPM across provider panels. What becomes the resampling unit and why?
  • How would you use the same replicates to test whether this year's PMPM differs from last year's, given the same members appear in both?

Turn overlapping coverage spans into fractional member-month denominators

Medium · intervals · gaps and islands · denominators

member_enrollment holds span_id, member_id, plan_id, product_type, effective_date and termination_date, which is NULL while the span is active. A member can hold several spans in a year, and back-dated plan changes make spans overlap. Return one row per calendar month of 2025 with total member-months, where a member contributes covered days in the month divided by that month's length, and a day covered by two overlapping spans counts once. Both span endpoints are inclusive. Collapse overlaps with window functions before joining a month calendar, and do not assume one span per member.

Approach

  1. Normalise the open end first. COALESCE(termination_date, DATE '9999-12-31') or clip to the reporting end, because a NULL termination_date makes every BETWEEN comparison unknown and drops exactly the members who are still covered.
  2. Merge overlapping spans per member before the calendar join. Order by effective_date, carry a running MAX of prior termination_date with a frame ending one row before, and open a new island where effective_date exceeds that running max plus one day, which keeps adjacent spans contiguous rather than splitting them.
  3. Clip each merged island to the reporting year, then cross join to a twelve-row month calendar and keep pairs that intersect.
  4. Compute covered days as LEAST(island_end, month_end) minus GREATEST(island_start, month_start) plus one, and divide by the actual length of that month rather than a flat 30, so February and the 31-day months are not distorted.
  5. Sum the fractions by month. Merging after the calendar join also works but forces a DISTINCT over member-days, which stops scaling at population size.

Worked solution (30 min)

  1. CTE bounded: clip spans to 2025-01-01 through 2025-12-31 with COALESCE on termination_date, discarding spans that do not intersect the year.
  2. CTE merged: gaps-and-islands per member using LAG and a running MAX over preceding rows to collapse overlapping and adjacent spans.
  3. CTE months: twelve rows of month_start, month_end and days_in_month.
  4. Join merged to months on interval intersection and compute covered_days per pair.
  5. SUM(covered_days / days_in_month::numeric) grouped by month, ordered by month.

Expected result: Twelve rows of (month, member_months) with fractional values. Any single member contributes at most 1.0 to a month and at most 12.0 across the year. A member covered 2025-01-01 through 2025-02-20 contributes 1.0 in January and 20/28 = 0.714 in February.

Verify it yourself

  • For a member with spans 2025-01-01..2025-03-31 and 2025-03-15..2025-06-30, March contributes exactly 1.0, not 1.5.
  • Total member-months is at most 12 times COUNT(DISTINCT member_id) and at least the count of members covered the whole year.
  • Forcing every termination_date to NULL raises the total. If it drops to zero, the NULL handling is missing.

Follow-up

  • Where does a continuous-enrolment filter with an allowable 45-day gap belong, and how does that change the island boundary rule?
  • One human appears under two member_ids after a master person index merge. What does that do to member-months, and how would you detect it?
  • How do you treat a span that terminates on the day it starts, and what does that row usually represent?

Measure ninety-day primary care contact for an enrollment cohort

Easy · cohort analysis · conversion rate · date windows

member_enrollment gives span_id, member_id, product_type, effective_date and termination_date, which is NULL while a span is active. medical_claim_line gives member_id, service_start_date, procedure_code and claim_status. The cohort is members whose earliest 2025 span has effective_date in January 2025 and who stay covered at least 90 days from it. Return, by product_type, cohort size and the share with at least one paid claim line whose procedure_code is in a supplied list of evaluation-and-management office visit codes and whose service_start_date falls in the half-open window from effective_date to effective_date plus 90 days.

Approach

  1. Build the cohort as one row per member before touching claims. Take the earliest 2025 span per member, require its effective_date in January, and require coverage to effective_date + 90 days, which means termination_date IS NULL OR termination_date >= effective_date + 89.
  2. Use EXISTS for the numerator rather than a join. A member with four office visits must count once; joining and counting rows inflates the numerator and can push the rate above 1.
  3. Keep the window half-open and anchored per member. Every member has a different effective_date, so a single fixed calendar window is a different metric and will not match the cohort definition.
  4. Aggregate numerator and denominator in one pass with a conditional sum grouped by product_type, and carry the raw counts alongside the rate so the reader can see the denominator.
  5. State the reportability rule on the output: the January cohort is not final until 90 days plus professional-claims runout have passed, so label the paid-through date.

Follow-up

  • A member changes plan on day 40, closing one span and opening another. Is she still in the cohort, and which product_type does she report under?
  • What moves if denied lines are allowed into the numerator, and which definition is right for an access metric?
  • How would you show this as a cumulative curve by day since effective_date instead of one 90-day point?

Describe a basic biostatistics framework you would use to analyze a randomized clinical trial with a binary outcome.

Medium · a/b testing and experimentation

Approach

  1. Name the guardrails that would stop a launch even on a positive primary result.
  2. Name the randomisation unit first; it decides the variance and what the test can detect.
  3. State the primary metric and the minimum effect worth shipping, then size the test.

Follow-up

  • How would you handle interference between treated and control units?
  • What would you do if you could not randomise at all?

How do your personal career goals align with the mission of Fred Hutch Cancer Center?

Medium

Approach

  1. State your assumptions explicitly before working the problem.
  2. Work from the decision backwards to the evidence you would need.
  3. Say what you would check first and why it is the highest-information step.

Follow-up

  • How would you know your answer was wrong?
  • What assumption would you test first?

Walk me through your most complex data science project, focusing on your specific contributions and the ultimate impact.

Medium

Approach

  1. Clarify what is being asked and what a complete answer would contain.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.

Follow-up

  • How would you know your answer was wrong?
  • What assumption would you test first?

Estimate a programme effect at a fixed risk-score enrolment cutoff

Medium · regression discontinuity · regression to the mean · local average treatment effect

Care management enrols members whose prospective_risk_score in member_enrollment crosses a fixed annual threshold of 1.75; above the line enrolment is near-automatic and below it unavailable, and about 85 percent of members above the line actually enrol. Leadership refused a randomised holdout and wants the programme's effect on next-year allowed PMPM. Two years of scores and claims are available. State the design, the estimand it identifies, the assumptions, and the diagnostics you would run before reporting anything.

Approach

  1. Propose a fuzzy regression discontinuity on prospective_risk_score at 1.75. Uptake jumps but is not complete, so the estimator is the ratio of the jump in outcome to the jump in enrolment probability at the cutoff, which is a Wald ratio.
  2. State the estimand honestly up front: a local effect for members near 1.75, who are the least sick enrollees. It does not identify the effect on the top risk decile, which is usually the number leadership actually wants, and saying so before the result lands is what keeps the analysis credible.
  3. Say explicitly why the obvious alternative fails. A pre-post on enrolled members selects on a high score in year one, and such cohorts regress toward the mean in year two whether or not anything is done, so a pre-post design reports savings every time. The discontinuity is immune because it compares members on either side of an arbitrary line.
  4. Specify the estimation: local linear fits on each side, triangular kernel, a data-driven MSE-optimal bandwidth, and robust bias-corrected inference rather than a naive local-linear confidence interval. Do not fit a high-order global polynomial.
  5. Run the falsification suite before looking at the effect: a density test for manipulation of the running variable, continuity of pre-determined covariates at the cutoff, sensitivity across bandwidths, and placebo cutoffs away from 1.75.

Worked solution (30 min)

  1. Plot the outcome and the enrolment rate against the centred running variable in uniform bins to confirm a visible jump in both.
  2. Estimate the first stage (jump in enrolment probability at 1.75) and the reduced form (jump in next-year PMPM), then take the ratio for the fuzzy RD estimate.
  3. Select the bandwidth by an MSE-optimal rule with a triangular kernel and local linear fits, and report robust bias-corrected intervals.
  4. Run the density test at 1.75 and the covariate continuity tests on age, prior-year cost, dual_eligible_flag, and product_type.
  5. Re-estimate at 0.5x, 1x, and 2x the selected bandwidth, and at placebo cutoffs of 1.50 and 2.00.

Expected result: A fuzzy RD estimating a local average treatment effect on compliers near the 1.75 cutoff, equal to the outcome jump divided by the enrolment jump, with local linear fits, a triangular kernel, an MSE-optimal bandwidth, and robust bias-corrected inference. The result is explicitly not generalisable to the highest-risk members.

Verify it yourself

  • The density test should show no discontinuity at 1.75; a spike just above the line indicates manipulation and invalidates the design.
  • Pre-determined covariates should show discontinuities indistinguishable from zero at the cutoff.
  • The point estimate should be stable across 0.5x, 1x, and 2x bandwidth.
  • Placebo cutoffs away from 1.75 should return null effects.

Follow-up

  • Risk scores are built from coded diagnoses, and coding intensity is something people can influence. What would manipulation look like in the density, and what do you do if you see it?
  • The MSE-optimal bandwidth leaves 900 members. How do you decide whether to report an underpowered estimate at all?
  • Design an encouragement version instead: randomise the invitation rather than enrolment. What does instrumental variables buy you, and which assumption is most at risk?

Readmission rate rose while every facility improved

Medium · simpsons paradox · mix shift · risk adjustment

Quarter over quarter the 30-day unplanned readmission rate for an attributed population rose from 14.2 to 15.1 percent, yet all eleven facilities in encounter show a flat or falling rate over the same period. You have encounter (facility_id, admit_ts, discharge_ts, encounter_type, admission_type, discharge_disposition, drg_code, is_planned_admission, index_encounter_id) and twelve months of prior medical_claim_line for comorbidities. Explain the direction reversal numerically, and state what the population-level number should be reported as instead.

Approach

  1. Confirm the reversal is arithmetic, not a definition difference, by recomputing both the facility rates and the pooled rate from the same query with the same index-stay exclusions.
  2. Decompose the pooled change exactly with a Kitagawa split. With facility weights w and within-facility rates r, the change equals the sum over facilities of (w_1 - w_0) times (r_0 + r_1)/2, the mix term, plus the sum of (w_0 + w_1)/2 times (r_1 - r_0), the within term. If the mix term exceeds the total change and the within term is negative, the reversal is volume shifting toward facilities with higher baseline rates.
  3. Ask why the weights moved. Check index-stay volume by facility, and check whether an exclusion changed behaviour: acute-to-acute transfers (discharge_disposition 'transfer_acute') must not open an index stay, and if one facility began transferring more, its denominator shrinks toward its sickest retained patients.
  4. Check case mix inside the facilities too, using drg_code and comorbidities drawn from the 12 months of claims before admit_ts, excluding complications of the index stay itself. A facility rate can be flat while its case mix worsens.
  5. Replace the raw pooled rate with an observed over expected ratio, where expected is the sum of predicted probabilities from a model fitted on age, sex and prior comorbidities. Raw rates are not comparable across a population whose facility and case mix is moving.

Follow-up

  • Your O/E ratio is 1.04 with a 95 percent interval of 0.96 to 1.13. What does that let you say to a facility, and what does it not?
  • If one facility contributes 40 percent of index stays, how does that change how you present the decomposition?
  • How would you handle a member with two index stays in the quarter, where the second is also a readmission from the first?

Suggested practice checklist

For someone who can already write the query and train the model but stalls when asked what to measure or whether a change is worth making. Metric definition and case structure come first; the technical work is kept as maintenance rather than the centre of the week.

Day 1 — Metric anatomy

  • For three products you use daily, write one primary metric, two input metrics that plausibly move it, and one guardrail that would catch a cheap way of moving the primary at the cost of the product.
  • For one of them, specify the metric precisely enough that two analysts would return the same number: numerator, denominator, unit of observation, time window, and how returning and deleted accounts are treated.
  • Pick a ratio metric and write what happens to it when the denominator shrinks for reasons unrelated to the numerator, with a concrete example of that happening.

Deliverable: A one-page metric tree for one product, with the primary metric written as an unambiguous spec.

Day 2 — Diagnosing a drop without guessing

  • Take the prompt "weekly active users fell 8 percent week over week" and write the segmentation plan before proposing any cause: platform, region, tenure cohort, acquisition channel, and whether the movement sits in the numerator or in a changed denominator.
  • List the instrumentation failures that manufacture fake drops (a client release that stopped firing an event, a bot filter change, a shifted date boundary or timezone) and write the query that rules out each one.
  • Rehearse stating the boring explanations first, seasonality and day-of-week composition, before reaching for a product cause.

Deliverable: A drop-diagnosis checklist short enough to recite from memory in under a minute.

Day 3 — Should we build it

  • Take a feature idea and write it as a bet: what you believe is true, what would have to be true for it to pay off, the metric that would confirm it, and the effect size that would justify the engineering cost.
  • Size the opportunity top-down and bottom-up, then reconcile the two numbers in writing instead of quoting whichever is friendlier.
  • Write the counter-metric that would make you kill the feature even if it wins on the primary metric.

Deliverable: A one-page product memo ending in a decision rather than a list of considerations.

Day 4 — The places aggregate numbers lie

  • Construct a Simpson's paradox numerically: two segments where the treatment wins within each segment yet loses overall, and identify the shift in segment weights that causes it.
  • Take a heavy right-tailed quantity such as revenue per user and write why the mean is the wrong summary, which percentile you would report instead, and what a moving mean with a stable median tells you.
  • Write your definition of a session for the product from day one, then name two real behaviours it misclassifies.

Deliverable: One page holding a worked Simpson's paradox table and a session definition with its two known failure cases.

Day 5 — Technical maintenance, aimed at metrics

  • Solve four timed SQL prompts that all end in a ratio metric, so the question of grain stays live in every answer.
  • Compute a 95 percent confidence interval for a proportion on a small sample, and state why the normal approximation is unreliable when either np or n(1 minus p) falls below roughly 10, along with which interval you would use instead.
  • Take one metric from your day-one tree, write the query that computes it correctly, then write the query that computes it wrong in the most plausible way and explain how you would notice.

Deliverable: Four solved prompts plus a matched correct and plausible-wrong query for one metric.

Day 6 — Turning engineering work into data science stories

  • Write three project stories as situation, decision, trade-off, outcome, each carrying one number and one thing you got wrong.
  • For the story you will lead with, prepare an answer to "what would you do differently" that names a decision you made, not a constraint you were handed.
  • Practise the sentence that reframes a systems project as a question project: the question the work answered, ahead of the pipeline it shipped.

Deliverable: Three written stories with the lead story delivered aloud and timed under four minutes.

Day 7 — Mock case and gap list

  • Run a 40-minute mock case with someone playing a product manager who pushes back on your metric choice, and record it.
  • Listen back and mark every moment you proposed a solution before the success metric existed.
  • Rewrite those moments as the question you should have asked, and rehearse the first 90 seconds of the case until scoping comes before solving.

Deliverable: A recorded case plus a rewritten opening 90 seconds.

Your part, not the team's

Most data work is done by groups, so an interviewer has to work out which piece was yours. An answer that runs on 'we' for several minutes gets interrupted with a question about what you personally did, and by then the answer sounds defensive even when it is true. Mark your own contribution as you go, and name the parts that belonged to someone else instead of leaving them ambiguous. Keep a few specifics back as well, like the name of the metric or who actually objected, so a probe can be answered with something you had not already said.

How do you handle missing clinical data in a longitudinal dataset?

Medium · behavioural and stakeholder questions

Approach

  1. Close with what you would do differently, concretely.
  2. Quantify the outcome, including what you would not claim credit for.
  3. Pick a story where you drove the decision, not one where you observed it.

Follow-up

  • How did you know the outcome was caused by your change?
  • What did you decide not to do, and why?

Describe a time you had to deliver a data science solution with highly ambiguous or incomplete requirements.

Medium · behavioural and stakeholder questions

Approach

  1. State the situation in two sentences and spend the rest on your reasoning.
  2. Pick a story where you drove the decision, not one where you observed it.
  3. Quantify the outcome, including what you would not claim credit for.

Follow-up

  • What would you do differently if you ran that project again?
  • What did you decide not to do, and why?

Can you describe a time when you had to learn a complex biological or scientific concept quickly to complete an analysis?

Medium · behavioural and stakeholder questions

Approach

  1. State the situation in two sentences and spend the rest on your reasoning.
  2. Name the disagreement or constraint, and how you resolved it with evidence.
  3. Pick a story where you drove the decision, not one where you observed it.

Follow-up

  • What did you decide not to do, and why?
  • What would you do differently if you ran that project again?