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Kharita Challenges

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Real geospatial problems, graded automatically. Choose a track, a level and what you want to hand in.

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Spatial Analysis5 problemsPostGIS / SQL1 problemPython1 problemRemote Sensing1 problemCartography2 problemsWeb GIS0 problemsData Management5 problemsGIS Architecture1 problem
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Data preparation0 problemsData quality1 problemSpatial analysis1 problemRaster analysis0 problemsCartography0 problemsDecision support1 problemGeospatial systems1 problemWeb delivery1 problem
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PostGIS / SQLAdvancedDecision supportClear all
  1. Not started, Which neighborhoods merit a service follow-up?Decision supportSQL

    Join geocoded service requests to neighborhood polygons and map a review share only where the sample supports it.

    PostGIS / SQLadvancedDifficulty: advanced390 XP~65 min8 checks

    You hand in a spatial SQL query.

    Datasets

    • 2020 Neighborhood Tabulation Areas · MultiPolygon · 262 features · EPSG:4326
    • NYC 311 sewer requests, 1–7 June 2025 · Point · 408 features · EPSG:4326

    What you’ll do

    • Join incident locations to neighborhoods with a boundary-inclusive predicate
    • Compute elapsed-time review share with a clear denominator
    • Suppress very small denominator areas before mapping percentages
    NYC 311PostGISspatial joinservice operationsgraduated mapAlso trains Spatial Analysis, Cartography, Data Management
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