# Glossary

| Term | Meaning |
|---|---|
| **10-year, 30-year** | US Treasury nominal yield at that maturity (FRED `DGS10`, `DGS30`) |
| **5y5y** | The 5-year, 5-year-forward breakeven inflation rate: the inflation rate the market prices for the five years starting five years from now. A gauge of long-run inflation expectations (FRED `T5YIFR`) |
| **2s30s** | 30-year yield minus 2-year yield, in basis points. The slope of the curve |
| **ACM term premium** | The extra yield investors demand to hold a 10-year bond rather than roll short bills, estimated by the NY Fed's Adrian-Crump-Moench model |
| **ALFRED** | The St. Louis Fed's archive of data as first published (vintages), used to see what was known at a past date |
| **Anchor test** | A test that a series matches a known historical value |
| **Basis point (bp)** | 0.01 percentage point |
| **Breakeven inflation** | Nominal yield minus TIPS real yield: the inflation rate at which the two bonds return the same |
| **Brier score** | Mean of (forecast probability − outcome)², with outcome 1 or 0. Lower is better; 0.25 is what always saying 50% scores |
| **Catalog** | `dataroom/catalog/series.yaml`: the contract that defines every series and how it is checked |
| **Cross-check** | Comparing a series with an independent source or an identity (for example 10y − 2y computed two ways) |
| **Direction-aware vote** | Back-test variant that scores inputs by their 12-month change and position against their own history, not fixed levels |
| **Driver score (Layer 2)** | Sum of seven structural drivers each scored −1 (pushing yields down), 0 or +1 (pushing up) |
| **Fingerprint** | A hash of a series' definition stored with its sign-off; a change voids the sign-off |
| **GSW** | Gürkaynak-Sack-Wright: the Federal Reserve Board's fitted zero-coupon nominal and TIPS yield curves |
| **HY OAS** | High-yield corporate bond spread over Treasuries (ICE BofA, on FRED). A measure of credit stress |
| **Interest / receipts** | Federal net interest payments as a share of federal receipts (BEA data). A measure of fiscal strain |
| **Kim-Wright** | An alternative term premium model from the Fed Board |
| **launchd** | The macOS scheduler that runs the daily refresh |
| **Overlay (shock overlay)** | A short episode (weeks to months), such as a fiscal scare or flight to safety, that does not by itself change the regime |
| **Parquet** | A compact column-based file format for tables |
| **r\*** | The neutral real interest rate (Holston-Laubach-Williams estimate, NY Fed) |
| **Raw store** | `dataroom/data/raw/`: gzipped original downloads with checksums |
| **Real-time data** | Data as it was first published, before revisions |
| **Regime A** | Disinflation: inflation at or below 2%, real 10-year below 1.25%, term premium near zero, 10-year 2.5–4%. Like 2002–2020 |
| **Regime B** | Higher real rates with anchored inflation: inflation about 2–2.75%, real 10-year 1.75–2.75%, term premium 0.25–1%, 10-year 4.25–5.75% |
| **Regime C** | Fiscal or inflation: inflation above 3% and rising, real yields falling while nominal yields rise, term premium above 1.25%, 10-year 6% or higher. Like 1965–1980 |
| **Regime vote** | Each of five headline metrics (5y5y, 10-year TIPS, term premium, policy vs long end, interest/receipts) votes A, B or C by its bands. A regime is called when it has 3 of 5 votes for 3 months running |
| **Register** | `dataroom/register/`: the audit register, cross-checks and regime votes as CSV |
| **Sign-off** | Your record, in `catalog/signoff.yaml`, that you have checked a series. Only you make it |
| **Splice** | Joining two series that cover different periods (here, the Fed Board 5y5y before 2003 and FRED's after) |
| **STALE / FAILED** | Register statuses: no new data within the series' staleness limit; a critical check failed (last good data kept) |
| **TIPS** | Treasury Inflation-Protected Securities. Their yield is a real (inflation-adjusted) yield (FRED `DFII10`) |
| **Vintage** | One published version of a data series on a given date |