The brief
Evidence Ledger is a product of Marketing MIX and our business group, so this case is about our own work. It grew out of a problem every marketer meets: advice about headlines, reviews, prices, scarcity or lead speed often comes with a percentage and no study behind it, or with a study that measured something else. A finding about how attractive a page looks gets quoted as a finding about sales. A correlation in one industry gets applied to another.
The brief was a research-first base for marketing decisions. Every consequential claim needs an identifiable primary source, observation must be kept apart from causal evidence, and null or contradictory results stay in the ledger. Then a reader-facing version had to let a business owner find a decision in a few seconds.
What we built
The ledger
The repository was started on 3 November 2026 with a source appraisal method, a record schema and a reading list limited to texts we have the right to keep. Each source card records the authors and year, the type of study, the sample, the outcome actually measured, the finding, the limits, a practical hypothesis and any study that contradicts it. Each decision card carries the funnel stage, the decision question, where it applies, the observed evidence, the boundary of the inference, a candidate change, an experiment, exclusions and a transfer confidence.
On 6 November 2026 the ledger held 78 sources and 44 decisions across stages from acquisition, consideration and trust to pricing, checkout, sales and retention. Two validators check every card and every cross-reference, and the 135 links between decisions and studies pass with no errors.
Rules for what may be claimed
The rules are written down before any synthesis. A correlational finding is never turned into a claim about conversion or revenue. A percentage from one industry or traffic source is never applied to another. Fake scarcity, invented testimonials and misleading metrics are excluded from what the ledger recommends. Focused reviews cover behaviour and messaging, page experience and conversion, the full funnel and measurement, choice architecture and pricing, creative and calls to action, and retention.
The public browser
The public page is built from the ledger's data files by a build script, so the page and the data cannot drift apart. It opens on a "receipt" header with the ledger totals: sources read, decisions mapped and grade-A sources. Below it, Decisions and Sources tabs, a search box and filters by funnel stage and topic lead to collapsible decision rows. Each row shows its evidence strength, and its drawer gives the observation, the boundary and the test. On a phone the stages scroll as cards, the filters open in a sheet and a dock stays at the bottom. That phone version shipped on 6 November 2026 together with the move to the short public address.
Where it stands today
On 8 November 2026 Evidence Ledger is live at evidence.mmix.biz in English. The header reads "Marketing decisions, with receipts" and "What research actually observed, where the evidence stops, and the smallest test that would settle it for your business." The footer reads "Evidence Ledger by INNOVA / MMIX · 78 sources, 44 decisions · built 2026-11-06" and notes that the quality grades are provisional.
Related
Research behind a plan: marketing analysis of the market and marketing strategy. Visibility in AI answers: LLM SEO and GEO. Another research product of ours: RootsLab.
Project lead: Marketing MIX. Product: Evidence Ledger, a marketing research base of our business group. Year: 2026.