a56916436249830dc5e866d656e2528a28b49d77927e54ce2c09c626e03ba597Methodology
Definitions are fixed by version. A research paper states which METHOD version it uses. Changing a definition creates a new version and the reason is recorded (Art. 32).
Time and business days
All times are recorded in JST and stated in ISO 8601 with the +09:00 offset. A business day is a weekday excluding Saturday and Sunday. Japanese public holidays are counted, because the price series exists on those days.
Episode variables
| Variable | Definition |
|---|---|
| Cost | Total intervention amount over the episode. MOF confirmed figures; where the period is not yet confirmed, press estimates are labelled ESTIMATE and kept separate. |
| Impact | High on the first intervention day minus the lowest low of the episode, in yen. |
| Efficiency | Cost divided by Impact. |
| Prior velocity | Mean absolute value of the four differences taken from the five closes preceding the first intervention day. |
| 50% recovery line | Episode low plus unrounded Impact multiplied by 0.5. Display is rounded; computation is not. |
| Effect half-life | Business days from the day after the last intervention day until the close first crosses back above the 50% recovery line. If it never does, the observation is right-censored and excluded from correlation analysis. |
The general rule for grouping nearby intervention days into a single episode is not yet formalised. The current six episodes are taken as enumerated in WP-001 §2.2. This gap is stated rather than concealed.
Survival window
From the business day after the last intervention day to the day before the half-life is reached. An event occurring on the day the half-life is reached is not counted as having occurred while the effect was alive. If the window is empty, the judgement is recorded as indeterminate.
Statistical policy
With fewer than eight observations we do not use p-values as grounds for a conclusion. "Statistically inconclusive" is treated as a legitimate research result (Art. 22). Criteria are preregistered before the resolving data arrives; post hoc changes and multiple-comparison searching are not performed (Art. 19).
Boundary of AI involvement
AI does not participate in generating the published data JSON or in numerical aggregation (Art. 12). AI is used for drafting and audit assistance only, and no AI output is accepted as fact without independent recomputation (Art. 14). A machine-audit PASS certifies internal consistency, not correctness of content (Art. 53).