Metrics question
How do you know there are enough shoppers for grocery orders at any given time and area?
- Instacart
- Metrics
- Hard
Practice this question out loud. An AI interviewer asks it, follows up like a real interviewer would, and scores your answer. Type or speak.
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What this question tests
Tests building a supply-demand balancing metric for a marketplace, requiring the candidate to define a measurable signal rather than a qualitative feeling.
How to approach it
- Define the question precisely: is there enough active shopper capacity to fulfill expected grocery order volume in a given zone and time window.
- Propose a core metric: the ratio of available shopper hours to forecasted order volume for each zone and time slot, a direct supply-to-demand ratio.
- Build the forecast side using historical order patterns by day of week, time of day, and local events or weather that spike demand.
- Build the supply side using shopper schedule and historical acceptance rate, since scheduled availability doesn't equal actual fulfilled capacity.
- Set a threshold, such as the ratio falling below a target level, that triggers a proactive action like surge incentives to recruit more shoppers for that slot.
- Validate the metric against a leading indicator: order wait time and unfulfilled order rate, confirming the ratio actually predicts real shortfalls.
What a strong answer includes
- Proposes a concrete, measurable ratio, shopper hours to forecasted order volume, instead of a vague check availability answer.
- Distinguishes scheduled shopper availability from actual historical fulfillment rate, since the two aren't the same.
- Uses illustrative numbers as assumptions: assume a target ratio of 1.2 shopper-hours per expected order-hour as the healthy threshold.
- Validates the leading metric against a real outcome, order wait time, closing the loop on whether the metric actually predicts shortages.
Common mistakes
- Proposing a qualitative check-availability answer without a measurable ratio or threshold.
- Treating scheduled shopper hours as equivalent to actual fulfilled capacity.
- Not validating the proposed metric against a real downstream outcome like wait time.
Likely follow-up questions
- How would you forecast demand for an unusual event like a snowstorm?
- What would you do in a zone that's chronically undersupplied?
- How would you incentivize shoppers to cover a predicted shortfall?
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More questions from Instacart
Learn the skill behind it
Chapters of the AI PM course that teach what this question tests.
- Chapter 9: Prove it paid off: outcomes, economics, and pricing
- Chapter 2: Data fluency: SQL, logs, and reading the truth yourself
- Chapter 14: Get the job: the AI PM interview loop