Log
2026-10-06 – Methodology change: weights computed per market; paired indices share weights and prices
Type: Methodology change · Announced: 2026-10-06 · Effective: 2026-10-26 (pricing, Perpetual indices) and 2026-11-01 (weighting) (announcement + at least 5 calendar days)- From November 1, 2026, weights will be computed from the market as a whole. A market’s weight will use the depth of its order book in contracts, instead of the dollar value of the outcome the index holds. Depth is the contracts resting in the best five price levels on each side, and each contract pays $1. Volume will be the market’s average daily volume over 30 days, instead of its 24-hour volume. A market will get the same weight whichever outcome an index holds. A market with no trades at all counts as zero volume. If a market’s 30-day volume isn’t available, it keeps its current weight. A market listed less than 30 days is averaged over the days it’s been listed (at least 7). If a market can’t be priced, has closed, or is held at zero weight, it keeps its current weight. At a pair’s re-weighting, it gets the average of its two weights. Today’s measure values each market at the price of the outcome held, which gives more weight to markets whose held outcome is already likely.
- From October 26, 2026, each market in a Perpetual index will be priced once per computation. An index holding NO will use one minus the YES price. Fixed indices will follow from a later date, announced separately.
- Paired indices will share weights. The two Perpetual indices in each linked pair hold the same markets on opposite outcomes. After each pair’s one-time re-weighting at the November 2026 review, both will use the same weights, computed once for the pair. Their raw index values will then add up to one (within rounding).
2026-10-06 – Correction: a removal from DGTUP and DGTDWN
Type: Correction Correction: On October 3, 2026, “Will Ethereum dip to $1,000 by December 31, 2026?” was removed from DGTUP and DGTDWN based on a misread trading-volume figure. The error is fixed, and published levels are not restated.2026-10-03 – Methodology change: rules for indices drawing on more than one venue
Type: Methodology change · Announced: 2026-10-03 · Effective: 2026-10-08 From the effective date, a standalone Perpetual Belief Index may draw constituents from more than one connected venue, screened and weighted by the same criteria and formula. No index changes on the effective date. Details: Market Selection & Weighting.2026-09-25 – Methodology change: resolved constituents leave at the next scheduled review
Type: Methodology change · Announced: 2026-09-25 · Effective: 2026-09-30 (announcement + 5 calendar days) Three changes to how Perpetual Belief indices treat resolved markets, applied from the October 2026 review:- Resolved constituents leave at the next scheduled review. A constituent whose market has resolved keeps its weight at its settlement value until the next scheduled review. At that review it leaves the composition, and the remaining constituents’ weights are scaled up in proportion so they again sum to one (a review that also adds markets re-weights the composition). The level is chain-linked across the change and does not jump. Until now a resolved constituent’s weight was set to zero at the next full reweighting while the market stayed listed, and a review without a full reweighting left its weight in place; a full reweighting also set to zero a market for which no live data was available; these cases now follow the rules above.
- A resolved constituent exits only on the venue’s settlement record. A resolved constituent leaves only once its venue’s final settlement record reports the outcome. A market the venue has closed but not yet settled, or whose data is temporarily unavailable, stays a constituent at its current weight until then; while it waits it is not tested against the maintenance criteria and its strike count is carried unchanged. Missing data never removes a constituent.
- Series in which every constituent has resolved. If every constituent of a Perpetual series has resolved, the constituents keep their settlement values, the level stays fixed, the series is shown as resolved, and it is considered for discontinuation under the cessation provisions.
2026-09-24 – Methodology change: volume screen, status-quo exclusion, continued eligibility
Type: Methodology change · Announced: 2026-09-24 · Effective: 2026-09-29 (announcement + 5 calendar days) Three changes to Belief Index constituent selection, applied from the October 2026 review:- Volume screen. The volume floor moves from 24-hour volume to 30-day average daily volume. The threshold is unchanged at $1,000 a day, so the maintenance floor becomes $500 a day on the same measure. A single day’s volume reflects the news cycle, while the screen exists to show that a market trades persistently.
- Status-quo exclusion. A market whose YES outcome is that a quantity is left unchanged when it could move either way – for example, a central bank holding rates – is ineligible for every Belief index. It cannot be held on a directional side, because its NO outcome pays on a move in either direction.
- Continued eligibility. A constituent must keep passing the published screens that describe the market itself (directional fit, binary outcomes only, one horizon per event, resolution clarity, and the category screens). A constituent that no longer does is deleted at the next scheduled review. Removals happen only on published grounds – these screens or the existing two-review maintenance rule – never on price or performance, and the ground for each removal is published. One current constituent meets this description and will be removed at the October 2026 review.
2026-09-24 – Note on published levels: USHAWK and USDOVE
Type: Level annotation · Affects: levels published from 2026-07-02 Since 2026-07-02, the Belief U.S. Monetary Policy Hawkish Stance Expectations Index (USHAWK) and its mirror, the Belief U.S. Monetary Policy Dovish Stance Expectations Index (USDOVE), have held “Will there be no change in Fed interest rates after the September 2026 meeting?”, a status-quo market with no directional side, at about half of each index’s weight from 2026-08-03. When the Fed raised rates on 2026-09-16, the market moved USHAWK’s level down and USDOVE’s up, against each index’s stated direction. Published levels stand as published and are annotated here rather than revised, so the record is treated the same way throughout. The October 2026 meeting’s equivalent market, held by the same pair, is the constituent to be removed at the October 2026 review under the continued-eligibility rule above.2026-09-21 – Venue eligibility screens adopted
Type: Methodology change · Announced: 2026-09-21 · Effective: 2026-09-26 (announcement + 5 calendar days) Belief Systems has published the screens a prediction market venue must meet before any published value may depend on its data – see Venue Eligibility. No published value changes.2026-09-06 – Cessation executed: U.S. Latin American pair (USLATINT26, USLATSQ26)
Type: Cessation (execution) · Noticed: 2026-08-02 · Executed: 2026-09-06 As noticed on 2026-08-02, publication of the Belief U.S. Latin American Intervention Expectations 2026 Index (USLATINT26) and the Belief U.S. Latin American Status Quo Expectations 2026 Index (USLATSQ26) ceased today. Final levels, fixed at the last valuation before cessation:- USLATINT26: 38.57, computed 2026-09-06 13:04:13 UTC
- USLATSQ26: 129.25, computed 2026-09-06 13:04:16 UTC
2026-09-05 – Clarification: where composition changes are published
Type: Policy clarification · Effective: 2026-09-05 Index Governance previously stated that scheduled reconstitutions would be disclosed in this log, and settlement exits recorded here at the next scheduled review. As of today it states where those disclosures actually live: the composition record. The Holdings table on each index page reflects a scheduled change at effectiveness, and the versioned composition downloads carry before-and-after membership, weights, and effective timestamps for every composition version. This log records methodology changes, corrections, cessations, and any composition change made outside a scheduled review. This follows the practice of established index administrators, who publish routine review results as constituent-change notices and reserve the governance record for departures from the rules. Nothing about the timing of disclosure changes: scheduled changes remain visible on the effective day. No published level or composition is affected.2026-09-05 – Composition repairs outside the review cycle: CONFLICT, PEACE, DGTUP
Type: Composition change (repair) · Effective: 2026-09-02 and 2026-09-03 · Disclosed: 2026-09-05 Three mirrored series received additions outside a scheduled review outcome. Each addition restores a market that an approved review had already admitted to the pair but that one side failed to carry. No selection rule, weighting formula, or eligibility threshold changed. What happened. Mirrored pairs hold the same markets on opposite sides. Under the governance framework, a market is admitted to a pair as a whole – both sides or neither. Until this week, the final investability screen (the 1% minimum-weight floor) was applied separately on each side at the moment of execution, against that side’s own composition. Because the two sides hold different legs with different liquidity, the same market could clear the floor on one side and miss it on the other. In the September review this produced three mismatches: DGTUP dropped a market DGTDWN kept, CONFLICT dropped a market PEACE kept, and PEACE dropped a market CONFLICT kept. One July 2026 addition to PEACE that never established had also remained open. Repairs. Each missing leg was re-added to the side that lacked it, at the weight the holding side already carried, with the remaining constituents scaled proportionally. Membership follows the approved review; execution outcomes do not edit it.
Before-and-after compositions and full weights are in the composition downloads. Levels are chain-linked across each change; no published level was restated.
Process correction. Two changes to the reconstitution process took effect on 2026-09-02 and 2026-09-04 so this cannot recur: a mirror’s execution now follows exactly the set its primary executed, and the minimum-weight screen for a mirrored pair is now decided once, for both sides together, when a proposal is submitted – not separately at execution. These are corrections to how the published rules were implemented; the rules themselves are unchanged.
One leg remains asymmetric. “Will Russia capture Kostyantynivka by December 31, 2026?” is held by CONFLICT only, at zero weight, because the market has resolved. It is a settlement exit, not a repair candidate; it no longer affects the level and stays listed at zero weight in the composition record until removed.
2026-08-09 – Launch notice: Belief Volatility and the Midterms Uncertainty Index (MIDVOL)
Type: Launch · Announced: 2026-08-09 · Effective: 2026-08-14 (announcement + 5 calendar days) Belief Systems will begin publishing a second benchmark family, Belief Volatility, on the effective date above. The first series is the Midterms Uncertainty Index (MIDVOL). Belief Volatility is a standardized estimate of how much prediction-market probabilities are expected to move over a stated horizon. It is not a directional view, not an investable product, and not an equivalent of an equity-market volatility index – the underlying is a probability, so the quantity being estimated is movement in belief, not in price. Values are quoted in probability points. MIDVOL measures the 2026 U.S. midterms balance-of-power distribution. Values publish at 1-day, 7-day and 30-day horizons; the bare ticker denotes the 30-day horizon. Full methodology, including a worked example reproducible from public information, is published at Belief Volatility methodology. On the effective date:- Official public history begins 2026-08-06 at 00:01:51 UTC, the first computation of the first complete day under the current methodology. Earlier computations were pre-launch testing and are not published. They are not deleted, and nothing published is ever restated.
- Values are withheld, never adjusted. Each value passes published publication gates covering order-book depth, spread, price impact, no-arbitrage bounds and input freshness. When a gate fails, the affected value is withheld with the reason stated. The gate parameters themselves are published, so any flag can be checked against the tolerance it was measured against.
- Corrections are appended, never rewritten. A corrected value publishes as a new revision at the same instant; the original stays exactly as published and remains retrievable.
- Retirement is prospective and one-way. As the 2026 midterms resolve and the underlying markets reach their boundaries, the composite retires to per-leg publication under the same ticker rather than renormalizing over whatever remains. Retirement is disclosed and cannot be reversed.
- History downloads. The public archive carries daily close rows, published in the monthly data drop, and remains downloadable for at least five years. The full 300-second panel is retained in the system of record and is available under licence.
2026-08-02 – Adoption of the Index Governance framework
Type: Methodology change · Announced: 2026-08-02 · Effective: 2026-08-07 (announcement + 5 calendar days) Belief Systems adopts a formal index governance framework, published at Index Governance. Material changes taking effect on the effective date:- Maintenance criteria and rules-based deletion. Constituents were previously never removed outside settlement. From the effective date, a constituent failing the published maintenance criteria at two consecutive monthly reviews becomes a deletion candidate, and an extraordinary-deletion path exists for integrity events. Deletions are rules-based – there is no discretionary removal.
- Monthly review window. Each index is reviewed against its criteria during the first seven calendar days of each month. The commitment is to the review; changes execute only when a review produces an approved change.
- Pair-level eligibility. For paired indices, a market is admissible only if both legs pass inclusion criteria, enforced before any change executes.
- Corrections regime. The existing no-silent-revision discipline is formalized: corrections above 10 basis points within 5 calendar days publish as labeled revisions with the original always retrievable; smaller or later errors are annotated.
- Transition provision. Adopting maintenance criteria over indices that predate them requires a starting point. The baseline audit of 2026-08-01 – every live constituent evaluated on both legs against the published criteria, from full order-book and volume data – counts as the first maintenance review for strike purposes. A constituent that failed the maintenance criteria at that audit carries one strike at adoption; if it fails again at the first post-adoption monthly review it becomes a deletion candidate under the two-strike rule, and if it has recovered its strike is cleared. The resulting strike determinations publish with the first post-adoption review. This is the only respect in which pre-adoption data enters the new regime; no other rule applies retroactively.