Choosing the Right Similarity Algorithm
Before choosing a similarity algorithm, understand whether your data uses binary membership (item has feature or doesn't...
JobClass
21 lessons
Lessons
Crosswalk and Taxonomy Evolution
Occupation codes are not stable identifiers across taxonomy revisions. The same SOC code can refer to different occupati...
Data Quality Traps in Government Sources
Government data sources contain artifacts of their internal production processes — temp files in archives, renamed colum...
Derived Metrics from Base Observations
Base observations are source truth; derived values are computed artifacts. Mixing them in the same table creates ambigui...
Design System Cross-Pollination
When two projects share an author, the stronger design system should inform the weaker one — but adopting visual feel is...
Dimensional Modeling for Labor Data
A four-layer warehouse architecture (raw, staging, core, marts) with strict separation of concerns at each layer produce...
Extract Patterns for Government APIs
Federal data sources are not designed for programmatic access. They block bare HTTP requests, publish in heterogeneous f...
Fetch Shim Architecture
A static site can replicate a dynamic API by intercepting JavaScript fetch() calls and redirecting them to pre-built JSO...
Geography Comparison Pitfalls
Geographic wage comparisons are inherently incomplete: nominal gaps do not account for cost-of-living differences, suppr...
Idempotent Pipeline Design
Data pipelines fail — downloads timeout, parsers hit unexpected formats, database connections drop. Idempotency (running...
Inflation Adjustment with CPI
Comparing nominal wages across years is misleading because the dollar's purchasing power changes over time. Converting t...
Multi-Vintage Query Pitfalls
Once a warehouse holds multiple vintages of the same dataset, every query must explicitly decide whether it wants the la...
Ranked Movers and Outlier Interpretation
Percentage changes on small bases are statistically volatile and can dominate ranked lists even when the absolute econom...
Schema Drift Detection
Government data sources change column names, add or remove columns, and retype columns between releases — often without ...
Static Site Generation
A server-side web application can be deployed to a static hosting platform by pre-rendering every page and API response ...
Testing and Deployment
Separating tests by their infrastructure requirements — fixtures-only, in-memory server, real database — lets CI run fas...
The Federal Labor Data Landscape
When building an analytical warehouse from multiple federal data products, the single most important architectural decis...
The Multi-Vintage Challenge
When loading multiple vintages of the same dataset, dimension tables must deduplicate on business key alone — not on bus...
Thread-Safe Database Connections
When a web framework dispatches synchronous endpoint handlers to a thread pool, a shared database connection will produc...
Time-Series Normalization
Fact tables store snapshots — single measurements at single points in time. Time-series analysis requires a separate nor...
UI-Data Alignment
A web application that shows buttons, links, or filters for data that does not exist creates a worse experience than one...