Archer Heights license records: a two-year renewal cycle, not a business-collapse measure

• Exploratory description, not a forecast, causal explanation or proof of a change.
• Approximate 95% factor intervals assume independent, constant-variance log residuals and fixed boundaries. They do not account for boundary search, serial dependence or source revisions.
• Confirmed zeros are treated as 1 only for fitting and its diagnostics. Raw counts stay zero; low-count results depend on this convention.
• Independent phase lines may jump at boundaries. Every observation belongs to exactly one phase.
• Reporting, classifications and seasonality can change. Counts are not population-adjusted; a level shift without a slope change is not the target of this search.
• Uses dated last-good cached data, not newly verified source counts.
• 1 confirmed zero fitted as 1; raw counts remain zero. Low-count trends are sensitive to this adjustment.
• At least one factor interval includes 1; its direction is uncertain under this approximation.
• License records include renewals and use license-term dates. Category/ward changes and administrative practice can affect counts; these are not business openings, closures or employment.
• Business frequency screening compares adjacent 24-month windows, requiring 48 complete months. The 12-month comparison is context only. Fixed two-year windows reduce renewal-calendar mismatch; they are not seasonal adjustment, proof of a renewal mechanism, or a test of stability.
• Window assessment: annual-only. Annual-only flags do not enter the frequency ranking. Opposite directions and short history must not be described as persistent changes.
• Many dependent filter conditions were searched. No multiple-testing-adjusted significance or causal attribution is claimed.
• Frequency compares fixed equal-length windows of raw counts, not population risk or a celeration-factor ratio. Reporting, classifications and exposure may have changed.

Intervals assume fixed boundaries and independent log residuals. They are not adjusted for the phase or filter search. Near-optimal boundary ranges are not confidence intervals.

Newest first. Unknown coverage is not a zero. These are the original saved observations, not fitted or rounded predictions.

Publisher dataset

Business Licenses · City of Chicago

Source retrieved

2026-11-05T21:09:58.696Z

Publisher update

2026-11-05T11:01:01.000Z

Covered months

October 2016–September 2026

Source note

Source xqx5-8hwx. Joint day/category/hour/applicable-flag/ward/status counts; no addresses, coordinates or incident identifiers. Each year's cells reconcile with an independent source total. Reads are not an atomic publisher snapshot. License records by term start, including renewals; not new businesses. Ward is as published, not reconstructed historical boundaries. Prepared daily community-area snapshot; scheduled rebuild at 06:00 America/Chicago. Full supported history is rechecked for corrections. Retrieval timestamps are preserved; this is not a real-time feed. Local indexed neighborhood snapshot. Totals are for the loaded area before other filters, not citywide totals. Citywide and unassigned-area views use a separate network-backed scope.

Snapshot

daily-v1:8a9771a7-dde2-4246-9cf6-d11519e895d6:neighborhood-v2:86fd007b4ddb5a845f1e22273b8c17e7

Discovery method

multi-feed-turn-and-frequency-renewal-v2

Analyze method

exploratory-segmented-log10-ols-zero-as-one-v3

Search plan

a3ffccedeb8d8ce18a30df3636839f775af1e5188e55a1f685695133135c6e35

Evidence run

817ae5c5ce03411a3c5680a546171629f627c699d9ee90e34f35fe1021144814