American Family Insurance · Data Scientist
Updated · 2026-09-24

American Family Insurance Data Scientist
Interview Questions & Guide 2026

THE 60-SECOND BRIEF

At American Family Insurance, a Data Scientist plays a pivotal role in transforming traditional insurance practices into data-driven, predictive operations. Insurance is fundamentally an industry built on assessing, pricing, and mitigating risk. By leveraging vast amounts of structured and unstructured data—ranging from telematics and property images to customer interactions and policy histories—data scientists build the predictive models that power the company's core products and strategic decisions.

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.

American Family Insurance candidates report 3 rounds · ≈ 3-5 weeks. The stages below are what candidates describe, not a published process.

Decompose expected loss into PD, LGD, EADReconcile amounts in minor units and currencySet fraud thresholds by expected cost

31 min read

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See the practice prompts

14Practice promptsAcross five skill areas
3With worked solutionsIncluded in the practice prompts

At American Family Insurance, a Data Scientist plays a pivotal role in transforming traditional insurance practices into data-driven, predictive operations. Insurance is fundamentally an industry built on assessing, pricing, and mitigating risk. By leveraging vast amounts of structured and unstructured data—ranging from telematics and property images to customer interactions and policy histories—data scientists build the predictive models that power the company's core products and strategic decisions.

The impact of this role is felt across the entire customer lifecycle. Your work will directly influence how policies are priced, how claims are triaged and automated, and how the company detects fraudulent activity. For instance, teams within the organization apply computer vision to assess property damage from aerial imagery, utilize natural language processing (NLP) to extract insights from policy documents, and build classic machine learning models to predict customer churn and lifetime value.

This is an inspiring yet highly rigorous environment. You will not just be training models in a vacuum; you will be solving complex, real-world problems that protect millions of families. To succeed, you must blend deep technical expertise in statistical modeling and software engineering with a strong business acumen, translating complex algorithmic outputs into actionable strategies for underwriters, actuaries, and product leaders.

01

Recruiter Screen

reported

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
PracHub interview research ↗
02

Technical Evaluation

reported

This round decides whether someone can hand you a schema and a question and trust the number that comes back. Correctness under a clock is the bar, not clever syntax. The habit that separates strong from weak answers is checking the grain: after every join, know how many rows you expect and whether the count moved. Most wrong answers in this format are not wrong logic, they are a fan-out from a key that turned out not to be unique, or a filter applied before an aggregate when it belonged after. Say what you expect before you run it.

What to demonstrate

  • Whether your row counts survive each join, and whether you notice on your own when they do not
  • Deliberate handling of rows that fail to match, including whether the question needs an inner join or a left join with the non-matches kept and counted
  • Whether NULLs are treated on purpose, given that a NULL compares equal to nothing and that COUNT of a column skips it
  • Reaching a defensible answer inside the window instead of a refined one after it

How to prepare

  • Take a two-table schema, write a join that fans out on purpose, then fix it by collapsing the many-side to one row per key before joining. Repeat until the fix is reflex rather than recall.
  • Write a funnel as one query and print the distinct user count at each stage, then confirm each stage is a subset of the one above it rather than assuming it
  • Do a few timed runs in a plain text box with no autocomplete and no formatter, since assessment editors often have neither
PracHub interview research ↗
03

Final Interview Rounds

reported

Where a loop includes a partner from outside the data team, that conversation usually carries the same weight as the technical ones and gets the least preparation. The person opposite you will not follow a derivation and does not need to. They are working out whether having you involved would make their decisions better or slower. The failure mode is not being too technical. It is answering a question about a decision with a description of your method, leaving the translation to them. What they carry into the debrief is the sentence you handed them, not the analysis underneath it.

What to demonstrate

  • Whether a statistical result arrives as something the partner could act on, with the one caveat that would change their decision kept and the rest left out
  • Whether you can state what you need from their side, in their terms: instrumentation that does not exist yet, a definition they own, or a holdout they have to agree to
  • Whether uncertainty is given as a range someone can plan against, rather than as hedging that invites them to ignore the result
  • Whether you ask what decision is actually on the table before explaining anything

How to prepare

  • Take a result you know well and write the version for someone who stops reading after one sentence, then the three-minute version, and check the short one is not the long one with the qualifications stripped out
  • For a past project, list everything you asked a non-technical partner for and how you phrased it, then rewrite each ask so it names what goes unmeasured without it
  • Practise saying where a result does not apply, out loud, in one sentence that a partner could repeat accurately to someone else
PracHub interview research ↗

PracHub editorial advice for the preparation topics above.

01

Counting authorizations instead of weighting them, and summing amounts across currencies

Declines skew toward high-value, cross-border and card-not-present transactions, so an unweighted approval rate can sit flat while approved value falls. Merchant retry logic also turns one declined purchase into several rows, inflating the denominator by an amount that varies by merchant and by decline reason. Amounts are held in the minor unit of the transaction currency and that unit is not always two decimals, since some currencies have none and some have three, so summing amount_minor across currencies produces a figure with no interpretation at all.

02

Assuming a model is fair because protected attributes are not among its inputs

Postcode, device, tenure, income proxies and even transaction patterns correlate with protected characteristics, so a model can produce a disparate outcome without ever reading the attribute. Credit decisions additionally carry an explainability obligation in many jurisdictions, since a denial has to be accompanied by its principal reasons, which constrains model form and feature engineering rather than being a reporting afterthought. Treating fairness testing and reason-code generation as design constraints from the first model version is far cheaper than retrofitting them to a deployed one.

03

Defining the cohort on a post-treatment condition

Ask how rows entered the table. Filtering on something that treatment itself influences, such as users who finished onboarding or accounts still active at ninety days, breaks comparability between arms; define the population at an entry point that precedes exposure and keep everyone in it.

04

Ending an analysis without a recommendation or next step

Close with what you would do and what would change your mind, stated as a condition you can check later. If the evidence is genuinely inconclusive, recommend the specific next measurement and say what it costs in time or exposure.

Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.

11 technical prompts3 include a worked solution

How do you handle extreme class imbalance when training a classificati…

medium
machine learning and modelling

How do you handle extreme class imbalance when training a classification model for fraud detection?

Approach
  1. Set a baseline first, so any model has something honest to beat.
  2. Say how the offline result would be validated online before it is trusted.
  3. Frame the prediction: the label, the moment of prediction, and the action it triggers.
Follow-up
  • How would you choose the decision threshold, and who owns that choice?
  • What would you monitor after launch to know the model is still valid?

Walk me through a machine learning model you deployed to production. W…

medium
machine learning and modelling

Walk me through a machine learning model you deployed to production. What were the data processing challenges, and how did you overcome them?

Approach
  1. Check what information would not exist at prediction time, and exclude it.
  2. Frame the prediction: the label, the moment of prediction, and the action it triggers.
  3. Pick an evaluation metric that matches the cost of each error type, not a default.
Follow-up
  • How would you choose the decision threshold, and who owns that choice?
  • What would you monitor after launch to know the model is still valid?

Estimate a delinquency roll-rate matrix and project twelve months

hardWorked solution
roll ratesmarkov chainsurvivorship

fct_loan_performance_monthly gives loan_id, as_of_month_end, months_on_book, delinquency_bucket, charge_off_flag, prepaid_in_full_flag and restructured_flag. Build a month-to-month transition matrix over the five delinquency buckets plus absorbing charged_off and prepaid states. Loans that stop appearing must be routed to an absorbing state rather than dropped. Project the current book forward 12 months by repeated matrix multiplication and report the projected share reaching charge-off. Handle restructured_flag explicitly, and name one place the Markov assumption fails on this data.

Approach
  1. Build consecutive month pairs per loan by shifting as_of_month_end within loan_id, then verify the shifted value is exactly one month later. A gap is not a transition, it is an exit you have not resolved yet.
  2. Resolve exits before counting anything. A loan whose last row carries charge_off_flag moves to charged_off, one carrying prepaid_in_full_flag moves to prepaid, and one that disappears with neither is a data question to raise rather than silently discard, because discarding it is survivorship that inflates every cure rate.
  3. Count pairs into a 7 by 7 matrix and row-normalise. Assert every row sums to one and the two absorbing rows are the identity; a row that does not sum to one means exits were dropped.
  4. Decide and state the restructure rule. Restructuring resets days_past_due, so a dpd_60_89 to current move on a restructured loan is not a cure. Either give restructured loans their own state or carry the pre-restructure bucket, but do not let that move land in the cure cell.
  5. Project by taking the current bucket distribution as a row vector and multiplying by the matrix twelve times. Report the charged_off entry, and report it again from an all-current starting vector so the reader can see how much of the projection comes from loans that are already delinquent today.
  6. State the homogeneity failure plainly: transition rates depend strongly on months_on_book, so one pooled matrix applied to a book with a young mix understates early-life delinquency. If the mix is moving, estimate separate matrices by seasoning band.
Worked solution 45 min
  1. Sort by loan_id and as_of_month_end, shift to form (from_state, to_state) pairs, and flag pairs whose month gap is not exactly one.
  2. For each loan's final row, assign the absorbing destination from charge_off_flag or prepaid_in_full_flag, and list loans that vanish with neither as an exception count to report.
  3. Apply the restructure rule, then build the 7 by 7 count matrix with a cross-tabulation over ordered state categories and row-normalise it.
  4. Assert row sums equal one and absorbing rows are the identity, then take the current month's bucket distribution as a row vector.
  5. Multiply twelve times, report the charged_off component, and repeat from an all-current vector for comparison.
EXPECTED RESULTA 7 by 7 row-stochastic matrix with identity rows for charged_off and prepaid, a current-to-current diagonal typically above 0.95, roll rates rising with bucket depth, and a 12-month projected charge-off share of a few percentage points from an all-current start and materially higher from the actual book.
Follow-up
  • How would you validate the projection against what actually happened, and over what window?
  • The cure rate out of dpd_30_59 rose five points last quarter. What are the candidate explanations and how would you separate them?
  • When would you prefer a vintage curve to a roll-rate projection, and why?

Roughly 90 minutes a night on weekdays with one longer weekend block. The plan deliberately cuts scope rather than compressing everything, on the assumption that finishing one thing a night beats half-starting four.

Small steps. Visible outcomes.0 / 7 completed
ONE WEEK · YOUR PACE

Prepare, practise & reflect

One practical outcome each day. Spend longer where you need it.

0 / 7 done
01Fix the scope and set a baseline
  • Read the role description and write the three things the loop will almost certainly test, then write an explicit not-doing list for everything else and keep it visible all week.
  • Take one 20-minute SQL prompt and one 10-minute metric question cold, and write the single sentence that says what blocked each attempt, since that sentence is what decides which two topics get the most evenings.
  • Set the week's one rule: one problem finished to completion every night, including the night you only have 40 minutes.

Deliverable: A one-page scope with an explicit not-doing list and two cold attempts, each carrying one sentence on what blocked it.

Practice prompt ↗Practice prompt ↗Worked solution ↗
02One query pattern, written three times
  • Choose the single pattern most likely to appear (a cohort retention grid, or a funnel counted by user) and write it three times from a blank file rather than editing the previous attempt.
  • On the third attempt, write the grain of every CTE as a comment before writing its body.
  • Stop at 90 minutes even if the third version is imperfect, and write the one thing you would fix with another hour.

Deliverable: Three independent versions of the same query plus a note on what changed between them.

Practice prompt ↗Practice prompt ↗
03Only the statistics you will be asked to defend
  • Write, in under 200 words, how you would decide whether a difference between two groups is real: the test, its assumptions, and what you would switch to when an assumption fails.
  • Compute a 95 percent confidence interval for a difference in proportions by hand on realistic numbers, then write in one sentence what changes if the two samples are paired rather than independent.
  • Write your answer to "what does a p-value mean", check it against a definition, and delete the version that describes it as the probability the hypothesis is true.

Deliverable: A 200-word written answer and one hand-computed interval you can reproduce under pressure.

Practice prompt ↗Practice prompt ↗
04One case, and the assumptions holding it up
  • Answer one product case aloud in 20 minutes with a recording running, then listen back with a pen and mark every claim you asserted without saying what it rested on: an assumed user behaviour, an assumed data source, an assumed baseline rate, an assumed grain.
  • Pick the three assumptions the recommendation actually depends on, write how you would check each one against data, and say which one being wrong would flip the recommendation rather than merely weaken it.
  • Write the four-step structure you used onto a card small enough to hold in working memory when you are nervous.

Deliverable: One recording, three load-bearing assumptions each with a written check, and a four-step structure card.

Practice prompt ↗Practice prompt ↗Worked solution ↗
05Your own work, timed
  • Write a 90-second version and a four-minute version of your main project, and time both out loud rather than reading them.
  • Prepare answers to the two follow-ups that always come: what you would do differently, and how you knew it worked.
  • Put one number in the first sentence and be able to say exactly where that number came from and what it excludes.

Deliverable: Two timed narratives with one defensible number in the opening line.

Practice prompt ↗Practice prompt ↗
06The one full rehearsal, in a longer weekend block
  • Run a 60-minute mock covering query work, a case and a behavioural question in a single sitting with no breaks, because sustained attention is the thing evenings have not trained.
  • Immediately afterwards, and before hearing any feedback, write the three moments you lost the thread.
  • Spend the rest of the block only on those three moments, and on nothing you merely feel shaky about.

Deliverable: Mock notes naming three failure moments with a specific fix written under each.

Practice prompt ↗Practice prompt ↗
07Taper
  • Write the 20-minute warm-up you will actually do on the morning of the interview: one query you can already write from a blank file, one metric you can define out loud, and nothing you have never seen before.
  • Re-read only your own notes from this week, and open no new material.
  • Write down the logistics: the tool you will be asked to work in, whether lookups are allowed, and the sentence you will use when you do not know something.

Deliverable: A one-page card holding the case structure, the project numbers, and the logistics.

Practice prompt ↗Practice prompt ↗Worked solution ↗

Expand any day for tasks and deliverables. Your progress is saved on this device.

Data people depend on systems owned by other teams, and much of the job is negotiating for instrumentation, access, or a fix to a broken pipeline. Prepare an example of getting something changed upstream that you did not control. Describe what you asked for, what you traded, and how you worked while you waited.

Describe your experience working with cloud environments. How would yo…

medium
behavioural and stakeholder questions

Describe your experience working with cloud environments. How would you architect a pipeline to train and deploy models using Google Cloud Platform (GCP)?

Approach
  1. Pick a story where you drove the decision, not one where you observed it.
  2. Name the disagreement or constraint, and how you resolved it with evidence.
  3. Close with what you would do differently, concretely.
Follow-up
  • What would you do differently if you ran that project again?
  • How did you know the outcome was caused by your change?

Describe a situation where you identified a business problem that coul…

medium
behavioural and stakeholder questions

Describe a situation where you identified a business problem that could be solved with data science, took the initiative, and delivered the solution.

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. Quantify the outcome, including what you would not claim credit for.
Follow-up
  • How did you know the outcome was caused by your change?
  • What would you do differently if you ran that project again?

Allocate one analyst-week across three competing risk requests

medium
prioritisationdecision deadlinesstakeholder negotiation

Three requests land in the same week and you have one analyst-week. Payments wants a merchant-level decline teardown before a contract renewal in nine days. Credit wants a swap-set analysis on a cutoff change scheduled to ship in six weeks. Insurance wants accident-quarter loss ratios at 12 months development for a reserving review with no fixed date. Each sponsor believes theirs is first, and each has escalated before. Produce the allocation, the reasoning you would say out loud to all three at once, and what you explicitly drop.

Approach
  1. Score each request on the decision it unblocks rather than on effort or on how loudly it arrived: what changes if it is late, and is that change reversible.
  2. Separate deadline from value. The nine-day renewal is a hard, irreversible date with a bounded prize; the six-week cutoff has slack but a much larger downside if it ships unmeasured; the reserving number has no date but feeds external reporting, which is its own kind of hard.
  3. Hunt for the cheap partial in each: a decline teardown restricted to the top merchants by declined value usually answers the contract question at a fraction of the full cut.
  4. Sequence by hard date first, then by largest irreversible downside, and deliver the trade-off to all three sponsors in one message rather than three, so nobody negotiates privately against a version you told someone else.
  5. Name what is dropped and who now owns that consequence, in writing, so the trade-off is visible rather than silently absorbed by you.
Follow-up
  • The credit sponsor escalates to your manager. What do you change, and what do you refuse to change?
  • How would you make this allocation reproducible so the next contested week is a rule application rather than a negotiation?
  • 01

    Describe your experience working with cloud environments. How would you architect a pipeline to train and deploy models using Google Cloud Platform (GCP)?

  • 02

    Describe a situation where you identified a business problem that could be solved with data science, took the initiative, and delivered the solution.

  • 03

    Three requests land in the same week and you have one analyst-week. Payments wants a merchant-level decline teardown before a contract renewal in nine days. Credit wants a swap-set analysis on a cutoff change scheduled to ship in six weeks. Insurance wants accident-quarter loss ratios at 12 months development for a reserving review with no fixed date. Each sponsor believes theirs is first, and each has escalated before. Produce the allocation, the reasoning you would say out loud to all three at once, and what you explicitly drop.

PracHub interview preparation framework ↗
Is this an official American Family Insurance interview guide?

No. It is PracHub's own research and practice material for the Data Scientist role at American Family Insurance. Rounds and questions reflect what candidates have reported, not a process American Family Insurance has published, and they change over time. Confirm the current format and scope with your recruiter.

PracHub interview research ↗
How difficult is the Data Scientist interview process?

The interview process is generally rated as average to difficult. The difficulty depends heavily on the specific team and your preparation level. While some rounds are highly conversational and focus on your past projects, the technical assessments (such as the coding challenge or the deep-dive ML questions) require a strong grasp of both programming and statistical theory.

PracHub interview research ↗
What is the balance between coding and machine learning theory?

The process evaluates both areas thoroughly. You will face a dedicated coding challenge or take-home project to verify your software engineering and data manipulation skills. Once that baseline is established, the final interviews pivot heavily toward machine learning theory, metric selection, and your ability to design practical data science solutions.

PracHub interview research ↗
Is experience with Google Cloud Platform (GCP) required?

While not always a strict requirement, familiarity with cloud environments—especially GCP—is highly valued. Many teams deploy their models and manage their data pipelines using cloud-native tools. Demonstrating that you understand how to leverage cloud resources for training and deploying models will significantly strengthen your candidacy.

PracHub interview research ↗
What is the work culture and work-life balance like for data scientists?

Employees consistently rate the work-life balance at the company very highly. The culture is collaborative, supportive, and professional. There is a strong emphasis on continuous learning, and team members are encouraged to explore new technologies and methodologies to solve business problems.

PracHub interview research ↗
Sources & methodology 3 sources ↗

No official company page is cited. Rounds and questions come from candidate reports and PracHub editorial material; each source shows the date it was read.