Chicago Crime Scene

Arrest Prediction

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Chicago Crime Scene

Arrest Prediction

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Chicago Crime Scene

Project Goals

  • Goal: Provide predictive guidance of likelihood of arrest.
  • Plan: determine rate of arrest per crime reports.
  • Method: use the dataset from the Chicago Data Portal.

Chicago Data Portal

  • Dataset available via the Socrata Open Data API
    (and bulk downloads).
  • Developed a SODA to SQL schema converter for import.
  • SODA access permits daily updates.
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Initial Models

  • Initial modeling seemed to show performance above baseline (of 80% accuracy).
  • Client wasn't necessarily impressed.
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Much about Metrics

  • Accuracy: Client already knows "most of the time" they don't get arrested.
  • Concern #1: If I say no arrest, and I get that wrong, they lose "staff". I need to be Sensitive of that.
  • Concern #2: If I say arrest, and I get that wrong, they lose "business". So I need to be Precise.

Crime by Communities

  • The dataset calls these "Location Areas".
  • These are the colloquial parts of town.
  • This is also the most general breakout.

Crime by Wards

  • The political districts
  • A bit more granular
  • Politicians draw much more convoluted shapes.

Crime by the Beat

  • Distrcit and Beat per the CPD.
  • District and Beat are they only purely heirarchical geo features.
  • Beat is much more granular.

Chicago Crime Scene

  • Geo Data was unpersuasive.
  • Time Data was meager.
  • Two remaining features proved very useful:
    • Location DESCRIPTION
    • Crime DESCRIPTION

Chicago Crime Scene

Model Results

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Arrest Predictor

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Appendix

Chicago Crime Scene

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Chicago Crime Scene

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Chicago Crime Scene

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Chicago Crime Scene

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Chicago Crime Scene

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Chicago Crime Scene

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