South Chicago: All categories — Graffiti requests

• 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.
• Boundary ranges show near-optimal models within 2 BIC units, not confidence intervals. They can be narrow even when the model is uncertain.
• A phase is at the minimum allowed length; its boundary may be sensitive to that search limit.
• 311 status is its value at retrieval, not at request creation. Newer cohorts have had less time to close; Open/Canceled comparisons can reflect workflow or cohort age rather than changing request volume.
• Current-system 311 coverage starts in 2019. Early phases may reflect adoption/reporting ramp-up; request counts are not completed work or incident prevalence.
• 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.

Near-optimal boundary range: January 2020–February 2020.

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

Publisher dataset

311 Service Requests · City of Chicago

Source retrieved

2026-11-06T12:10:53.153Z

Publisher update

2026-11-06T11:22:56.000Z

Covered months

January 2019–September 2026

Source note

Source v6vf-nfxy. 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. Current 311 system only, legacy_record=false; includes duplicate requests, not completed work. Status is as currently published, grouped by creation date—not historical status or completion date. 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:f761b44d-f9db-4d57-b536-48aea9b60f93:neighborhood-v2:92f1af8f0a1b4aae18f50286f6f292d6

Discovery method

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

Analyze method

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

Search plan

a3ffccedeb8d8ce18a30df3636839f775af1e5188e55a1f685695133135c6e35

Evidence run

a846fb8352d657c46389fbca17f7832ae0aa7914e1a467ca31cd1c277cec71ad