How we know what we know

OpenDelta holds 6,486 recorded facts about Delta State, from 88 sources. 3,741 of them — 58% — are notes of information not yet published, so a reader knows it is missing from the record rather than from this site.

Every source is named below, with what it gave and when it was collected. Every figure on a page also carries its own label, and every page links back to the record behind it.

Two of these have never been used. No instrument has ever reported a reading to this platform, and until the review queue opened there was no way for a citizen report to be published at all. They are listed because they are how the platform would record such a thing, not because it has — and a page about how we know things is the worst place to describe a capability in the present tense.

The short codes (T0 to T6) are how these appear in the API and in every download, so a researcher can filter on them. On the site itself you see the sentence instead.

Registers and reports the government publishes

Read from the publisher's own page or document, and used as published.

Maps and place lists

Delta State publishes no settlement or ward list, so the places on the map come from open mapping projects. Neither is an official register, and a place nobody has mapped is missing from both.

What OpenDelta worked out

Calculated here from the sources above, and never an official statistic. Each carries the method that produced it.

Catalogued, not loaded

22 sources we have found, checked and recorded the terms for, and which contribute nothing to any figure on this site yet. They are listed so the route to filling a gap is visible, not to suggest the gap is filled: BudgIT States Fiscal Transparency League and State of States, Community-generated observations (the missing dataset), Copernicus Sentinel-1 and Sentinel-2 satellite imagery, Corporate Affairs Commission, Corporate Affairs Commission company register, Delta State Auditor-General performance audits, Delta State Local Government audit reports, Delta State fiscal document library, Delta project register (Delta Project Monitoring), GRID3 Nigeria geospatial layers, Global Flood Database and Global Surface Water (JRC), IOM Displacement Tracking Matrix and ReliefWeb / HDX, NASA and partner precipitation and flood products (GPM/IMERG, GFMS, HydroSHEDS, SRTM/Copernicus DEM), NBS Consumer Price Index and selected food prices, NBS microdata catalogue (General Household Survey, Labour Force, NLSS), NERC orders, BEDC Band A feeder lists and NBET/NISO grid data, NOSDRA Nigerian Oil Spill Monitor, Nigeria Data Portal and open.africa, Nigeria Health Facility Registry / master facility list, OpenStreetMap, People in Delta State, World Bank, WHO, UNICEF, UNESCO, FAO and AfDB open data.

• Follow one figure back. Every page carries a How we know panel naming the document, the publisher and the day it was read.
• Take the whole thing. Data and downloads lists every source with what it contributed, and every dataset as CSV.
• Query it. The API returns the same records with their provenance attached, so a figure can be checked without using this site.
• Tell us we are wrong. The corrections log shows every correction received, including the ones we did not accept.

The representation layer names living people, which is a different kind of claim from a contract sum, so it runs under stricter rules than the rest of the platform.

• Only two sources may name a person. The National Assembly's own register of its members, and the Delta State Government's own website. Nothing else.
• Wikipedia is used for geography only. It tells us which LGAs make up each senatorial district — a structural fact we can check, because the three lists have to account for all 25 LGAs exactly. It is never allowed to name an office holder: its own article on Delta South still names a senator who left in 2023.
• Names are reproduced as published, misspellings included, so that a name here can be matched against the page it came from.
• We record offices, never conduct. Nothing on a person's page is an assessment of them. Money shown against a seat is what is registered in that area, not what anyone chose, controlled or delivered.
• Anyone named can respond, and the response is published beside the record through the same corrections process as any other figure.
• Where a register does not yet name a holder, we say so. 5 of Delta State's 42 elected seats have no name against them in the registers we can reach — recorded as 8 separate absences, because four of them are an area whose federal constituency is not yet published rather than a seat of its own. That gap is shown as plainly as any name.

• We publish measurements, never verdicts. "Past its completion date" is a fact. "Abandoned" is a conclusion we are not entitled to draw.
• We never rank politicians or parties. We rank places, contracts and contractors — entities that appear in official records in an official capacity.
• We never present a figure we calculated as an official statistic.
• We publish our own error rate and our own corrections, including the ones we rejected.
• Any organisation named here can have a response published beside its record — how the right of reply works.