Practice interviews

Does the AI summary describe the support backlog?

The generated summary says half of all messages concern refunds.

The question

Harbor Market reviews a sample to plan refund support staffing. Within each channel, the 50 reviewed messages were selected at random; the AI refund labels have not yet been checked by people.

Sampling export
Backlog messagesReviewedAI-labeled refund
Phone1005040
Email9005010

Authored data. Channels partition a backlog of 1,000 messages; one message is the unit.

AI-generated AI summary

50 of 100 reviewed messages mention refunds, so 50% of the backlog needs refund support.

“Audit the estimate and say what must happen before using it for staffing.”

A strong answer, step by step

Open each step in turn. This is one strong answer, not the only one.

Step 1: Find the sampling error

What would you do here? Open the move you’d make.

  • Inspect the sampling design

    The strong move. A balanced review sample is not a proportional sample.

  • Apply the pooled sample share to the full backlog

    Tempting, but it misses something. The rare high-refund channel is overrepresented in the review.

See how a strong candidate says it

“The sample gives each channel equal weight; the backlog is 10% phone and 90% email. The pooled 50% is a sample share, not the backlog share.”

What a strong candidate could say

Why it works: A balanced review sample is not a proportional sample.

Step 2: Reweight the labels

What would you do here? Open the move you’d make.

  • Average both channel rates

    Tempting, but it misses something. Equal channel weights repeat the original sampling error.

  • Weight channel rates by backlog

    The strong move. Population weights match the declared unit.

See how a strong candidate says it

“Phone’s labeled rate is 40/50 = 80%; email’s is 10/50 = 20%. Weighting by backlog gives 0.1×80% + 0.9×20% = 26%, or an estimated 260 messages, conditional on valid labels and representative within-channel samples.”

What a strong candidate could say

Why it works: Population weights match the declared unit.

Step 3: Inspect the uncertain labels

What would you do here? Open the move you’d make.

  • Validate the labels and their misses

    The strong move. Reweighting cannot fix a wrong label definition.

  • Use the weighted AI labels to set staffing

    Tempting, but it misses something. An exact arithmetic result can still be based on classification error.

See how a strong candidate says it

“Before staffing, manually audit a channel-stratified set, including ambiguous cases and non-refund labels. Define refund intent and check misses as well as false alarms. The 26% estimate still has sampling and classification error.”

What a strong candidate could say

Why it works: Reweighting cannot fix a wrong label definition.

Step 4: Recommend a reversible move

What would you do here? Open the move you’d make.

  • Allocate staff in proportion to labeled messages

    Tempting, but it misses something. The unit is messages; one issue can generate multiple messages.

  • Check handling time and repeat contacts

    The strong move. The resource decision requires a workload measure.

See how a strong candidate says it

“Use the validated, weighted estimate as one input to a short staffing trial. Messages are not tickets or minutes: measure handling time and repeat contacts before converting counts to headcount.”

What a strong candidate could say

Why it works: The resource decision requires a workload measure.

The answer, in short

Decision
Validate labels, then estimate weighted workload.
Because
The pooled review share overweights phone messages.
What would change it
A non-random within-channel review, label errors or very different handling times would require a new estimate.

Common traps

  • Reporting sampling output as population truth.
  • Converting messages directly to staffing.

Check your answer

  • Did you identify the 10/90 population weights?
  • Did you calculate 26% rather than 50%?
  • Did you state sampling and label uncertainty?
  • Did you check message counts before staffing assumptions?

Last reviewed Nov 10, 2026