Question 770
For Mercury Travel Tech, the engineer must verify a remediation with measured evidence, not just a deployment claim. The original failure was: A retraining system chooses its start conditions from wall-clock time alone even though new labels arrive irregularly and data quality sometimes falls below the minimum. Which independently observable result best verifies that the remediation works?
Explanation
Correct Answer
A no-new-label cycle skips training, while a clean newly labeled batch initiates an auditable run. This controlled observation specifically validates the proposed remedy: Trigger training only after recorded label readiness and data-quality conditions are satisfied, with optional scheduling as a guard. It addresses the documented failure at Mercury Travel Tech: A retraining system chooses its start conditions from wall-clock time alone even though new labels arrive irregularly and data quality sometimes falls below the minimum.
Incorrect Answers
A committed transform update produces a new versioned pipeline run and parity checks cover the changed features. This is evidence for a different corrective change: Include preprocessing code changes in CT triggers and verify the pinned transformation artifact before training. That other change addresses: A feature transformation changes in the Git repository but the CT pipeline retrains using the old preprocessing image without any compatibility test. It does not validate the specific Mercury Travel Tech remediation for: A retraining system chooses its start conditions from wall-clock time alone even though new labels arrive irregularly and data quality sometimes falls below the minimum. The necessary check instead is: A no-new-label cycle skips training, while a clean newly labeled batch initiates an auditable run.
A synthetic metric breach restores the last approved version and records the release incident. This is evidence for a different corrective change: Monitor predeclared release metrics and execute a tested rollback workflow when failure thresholds are breached. That other change addresses: A newly released model increases prediction error but the automated promotion workflow has no trigger to revert traffic. It does not validate the specific Mercury Travel Tech remediation for: A retraining system chooses its start conditions from wall-clock time alone even though new labels arrive irregularly and data quality sometimes falls below the minimum. The necessary check instead is: A no-new-label cycle skips training, while a clean newly labeled batch initiates an auditable run.
Version-tagged shadow outputs demonstrate candidate quality and latency within the approved acceptance envelope. This is evidence for a different corrective change: Run shadow or offline-challenger evaluation against production-representative inputs prior to traffic promotion. That other change addresses: A newly retrained model is promoted directly into production before any shadow comparison with current predictions. It does not validate the specific Mercury Travel Tech remediation for: A retraining system chooses its start conditions from wall-clock time alone even though new labels arrive irregularly and data quality sometimes falls below the minimum. The necessary check instead is: A no-new-label cycle skips training, while a clean newly labeled batch initiates an auditable run.