What data wrangling challenge arose from different jurisdictions reporting case numbers?

The need to clean, verify, and normalize data reported using different methodologies or time stamps.

A major challenge faced by the team was the lack of uniformity in how various health departments reported their figures. For instance, one jurisdiction might report based on the date a patient was tested, while another reported based on the date a laboratory officially confirmed the result. Simply aggregating these raw numbers together without reconciliation would lead to inaccurate totals. Therefore, a significant part of the engineering effort involved creating rigorous processes to normalize and clean this data so that figures from different areas could be accurately combined on the unified map.