Question 10
At Northgate Telecom, the network analytics engineers maintain service incident prediction and telemetry classifiers under requirements for streaming integrity and scalable model monitoring. Following the controlled change, the team validates: A data engineering job stores a large column-oriented training dataset as thousands of verbose JSON files and suffers excessive scan costs in Athena. Which observed result BEST demonstrates that the correction works?
Explanation
Correct Answer
The benchmark query scans fewer bytes and still returns identical approved training rows and feature values. This is observable proof for correction of: A data engineering job stores a large column-oriented training dataset as thousands of verbose JSON files and suffers excessive scan costs in Athena. The approved design change is: Convert the curated training data to partitioned Parquet with column statistics and choose partitions aligned to actual predicates. The Northgate Telecom acceptance test separates measured ML behavior from an unverified implementation claim.
Incorrect Answers
A controlled rebuild with the same recipe and source manifest reproduces feature checksums and row counts. This would verify a different operation: Record and deploy a specific reviewed recipe version together with input snapshot identifiers for every training dataset build. That separate action addresses: An AWS Glue DataBrew recipe is edited directly in production and a rerun cannot reproduce the original training features. It cannot establish the required Northgate Telecom correction for: A data engineering job stores a large column-oriented training dataset as thousands of verbose JSON files and suffers excessive scan costs in Athena. The decisive acceptance check is instead: The benchmark query scans fewer bytes and still returns identical approved training rows and feature values.
The final report records positive-class recall and precision on the original distribution, not only inflated aggregate accuracy. This would verify a different operation: Measure class balance and compare stratified resampling or class weighting on training data while preserving an untouched evaluation set. That separate action addresses: A marketing propensity model has a class distribution of 98 percent negative examples and selection by accuracy alone hides poor positive detection. It cannot establish the required Northgate Telecom correction for: A data engineering job stores a large column-oriented training dataset as thousands of verbose JSON files and suffers excessive scan costs in Athena. The decisive acceptance check is instead: The benchmark query scans fewer bytes and still returns identical approved training rows and feature values.
An input set with mixed-capitalization labels maps consistently while an unknown label triggers the declared quality exception. This would verify a different operation: Define a validated label encoding dictionary and reject unmapped target values before model training starts. That separate action addresses: A binary target is stored as strings with inconsistent capitalization and preprocessing silently maps one valid positive class to negative. It cannot establish the required Northgate Telecom correction for: A data engineering job stores a large column-oriented training dataset as thousands of verbose JSON files and suffers excessive scan costs in Athena. The decisive acceptance check is instead: The benchmark query scans fewer bytes and still returns identical approved training rows and feature values.