Research/Terra/ 785163
Task evidence / population-distance-share

Calculate the percentage of Angola's population living within 20km of mineral extraction facilities

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

785163
Calculate the percentage of Angola's population living within 20km of mineral extraction facilities
Exact submitted task and declared adaptations
Calculate the percentage of Angola's population living within 20km of mineral extraction facilities

Task conventions: Use the frozen WorldPop 2020 UN-adjusted population-count raster, original band 1 and grid; values are people per cell. Use the supplied facilities records with Country exactly 'Angola'. Do not invent missing facilities or include another country. A valid population cell qualifies when its centre is at most 20000 metres from its nearest selected original Point, using shortest WGS84 ellipsoid surface distance. This frozen centre-distance convention avoids overlapping-buffer double counts and projected-map scale ambiguity. It is not road travel distance or within-cell population positioning. Sum original counts in qualifying cells, divide by all original valid country-raster counts and multiply by 100. No resampling, constant-cell-area conversion or invented census denominator. Zero population stays valid; NoData is unknown. Count each cell once. The result describes the supplied facility inventory and raster coverage, not proof that every facility is recorded. Retain the full-grid distance raster and selected-population raster (original count when eligible, zero otherwise, original missing-data mask).



Compute the percentage and publish both inspectable rasters. A map is optional. End with a fenced JSON object: {count: qualifying cell count, unknown_count: original masked/nonfinite cell count, coverage_note, selection:{collectionId,itemId,assetKey}, distance:{collectionId,itemId,assetKey}, metrics:{selected_people:number,total_people:number,percentage:number}}. Label selected population as people per cell and distance as metres. Report the historical year and coverage limitations. Do not round machine-readable metrics to integers.

Delivery format: provide the answer object with all fields specified above as final_response on assess_result, alongside the inspected final artifact_refs. This replaces the JSON-code-block formatting requirement above. Blue attaches your explicit selection to the accepted final answer. Finish with a concise ordinary-language answer agreeing with that selected result; do not duplicate the JSON in chat.

Supplied immutable inputs:
[
  {
    "name": "Angola population count, WorldPop 2020",
    "edition": "2020 UN-adjusted population aggregated to 1 km cells",
    "units": {
      "band1": "people per cell"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "African mineral extraction facilities",
    "edition": "USGS 2021 benchmark snapshot",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
22m 4s
Recorded Blue tool calls
64
Total tokens
2,841,834
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

About 43.02% of the population in the supplied Angola WorldPop 2020 raster lives within 20 km of a supplied Angola mineral extraction facility. That is 14,137,536.462 people out of 32,866,268.004 valid people-per-cell counts; 21,584 cells qualify. The Angola filter kept 53 supplied records, which collapse to 49 unique point locations because four coordinate pairs are duplicates. Limits: this uses the supplied WorldPop 2020 raster and supplied USGS 2021 facility snapshot. 947,409 masked raster cells remain unknown, and the result describes the supplied raster coverage and inventory only. Next: I can add the published selected-population raster and distance raster to the map if you want. ### Limitations - Population values are from the supplied WorldPop 2020 UN-adjusted 1 km raster; masked or nonfinite cells are excluded as unknown. - Facilities are from the supplied USGS 2021 benchmark snapshot; the result reflects this supplied inventory only and does not prove all facilities are recorded. - Distance uses original raster cell centres and shortest WGS84 ellipsoid surface distance to the nearest selected point; it is not road distance or travel time. - Population values come from the supplied WorldPop 2020 UN-adjusted 1 km raster; 947409 masked cells are unknown and excluded from totals. - Facilities come from the supplied USGS 2021 snapshot; the result reflects this supplied inventory only and does not prove that every Angola facility is recorded. - Distance is original raster cell-centre WGS84 ellipsoid distance to the nearest selected point, not road travel distance or within-cell population location.

Independent checks

These checks are separate from the agent's own assessment. A successful job or an assertion of success is not enough to pass.

Expected count
21584
Reported count
21584
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 21584,
  "actualCount": 21584,
  "expectedMetrics": {
    "selected_people": 14137536.462073088,
    "total_people": 32866268.004241593,
    "percentage": 43.015338584376394
  },
  "actualMetrics": {
    "percentage": 43.01533858437639,
    "total_people": 32866268.004241593,
    "selected_people": 14137536.462073088
  },
  "computationCorrect": true,
  "answerFulfilled": true,
  "adjudication": null,
  "qualification": null,
  "reasons": []
}

Recorded investigation findings

The agent's reported hypotheses and assessments, retained as evidence of its process—not independent proof that the answer is correct. Failed calls retain their requested verdict, not an accepted assessment.

run_trial · completed

Does the full Angola computation correctly filter the supplied facilities to Country='Angola', compute WGS84 cell-centre nearest-point distances on the original WorldPop grid, and produce selected-population and summary rasters that preserve the original missing-data mask?

assess_trial · completed · assessment: sufficient

The full-area test answered the method question. The supplied facilities filter returned 53 records with Country='Angola'. Inspection of the filtered coordinates shows 4 duplicate point locations, so the distance processor's 49 effective point locations are consistent with exact duplicate pruning and do not change nearest-distance or eligible-cell results. The geodesic distance raster preserved the original WorldPop grid and missing-data mask and reported metres. The selected-population raster preserved the original mask, wrote original people-per-cell values within 20 km, and wrote zero outside. The full-grid statistics reconciled without double counting: total_people=32866268.004241593, selected_people=14137536.462073088, qualifying valid cells=21584, unknown cells=947409.

assess_result · completed · assessment: sufficient

43.01533858437639% of the people counted in the supplied Angola WorldPop 2020 raster are in valid cells whose centres are within 20000 metres of the nearest supplied Angola mineral extraction facility. The final published outputs preserve the original raster grid and mask. Final metrics from the published outputs are selected_people=14137536.462073088, total_people=32866268.004241593, qualifying valid cells=21584, and unknown masked/nonfinite cells=947409. The final Country='Angola' facility filter contains 53 supplied records; 4 duplicate coordinate pairs collapse to 49 effective point locations in the geodesic distance raster without changing nearest-distance eligibility.

Recorded workflow

  1. 01

    Angola population within 20 km of supplied mineral extraction facilities

    Recorded output · succeeded

  2. 02

    Angola nearest-facility distance raster

    Recorded output · succeeded

  3. 03

    Selected population summary

    Recorded output · succeeded

  4. 04

    Total population summary

    Recorded output · succeeded

  5. 05

    Qualifying cell summary

    Recorded output · succeeded

  6. 06

    distance

    Recorded distance-surface · succeeded

  7. 07

    facilities angola

    Recorded vector-filter · succeeded

  8. 08

    mask stats

    Recorded raster-statistics · succeeded

  9. 09

    population band

    Recorded raster-extract-band · succeeded

  10. 10

    selected population

    Recorded raster-point-proximity · succeeded

  11. 11

    selected stats

    Recorded raster-statistics · succeeded

  12. 12

    selection mask

    Recorded raster-point-proximity · succeeded

  13. 13

    blue-generated--[resource id withheld]

    Recorded source · succeeded

  14. 14

    blue-generated--[resource id withheld]

    Recorded source · succeeded

  15. 15

    total stats

    Recorded raster-statistics · succeeded

  16. 16

    distance

    Recorded distance-surface · succeeded

  17. 17

    facilities angola

    Recorded vector-filter · succeeded

  18. 18

    mask stats

    Recorded raster-statistics · succeeded

  19. 19

    population band

    Recorded raster-extract-band · succeeded

  20. 20

    selected population

    Recorded raster-point-proximity · succeeded

  21. 21

    selected stats

    Recorded raster-statistics · succeeded

  22. 22

    selection mask

    Recorded raster-point-proximity · succeeded

  23. 23

    blue-generated--[resource id withheld]

    Recorded source · succeeded

  24. 24

    blue-generated--[resource id withheld]

    Recorded source · succeeded

  25. 25

    total stats

    Recorded raster-statistics · succeeded

  26. 26

    distance

    Recorded output · succeeded

  27. 27

    total stats

    Recorded output · succeeded

  28. 28

    selected stats

    Recorded output · succeeded

  29. 29

    mask stats

    Recorded output · succeeded

Activity

Recorded actions

Recorded observable actions only, not private reasoning. Raw payloads, geometry, private links and credentials are omitted; full evidence is retained privately. Activity/workflow lists bounded at 500 entries.

  1. Progress update

    I’m checking the saved analysis context, the two supplied sources, and the available geospatial processors so I can build the exact centre-distance method you asked for and publish inspectable rasters.

  2. get_analysis

    Recorded tool call · completed

  3. get_collection

    Recorded tool call · completed

  4. get_collection

    Recorded tool call · completed

  5. search_catalog

    Recorded tool call · completed

  6. Progress update

    I found the core Blue tools. Next I’m inspecting the two supplied datasets and an authoritative Angola boundary so the computation uses the original raster, the exact Angola facility filter, and an explicit country scope.

  7. Progress update

    The supplied raster looks like an Angola-only snapshot, but I still need a real boundary source so the study scope is explicit and I can describe any edge coverage limits correctly. Then I’ll inspect the file schemas and test the exact distance workflow on a small slice.

  8. list_processors

    Recorded tool call · completed

  9. search_catalog

    Recorded tool call · completed

  10. get_collection

    Recorded tool call · completed

  11. get_collection

    Recorded tool call · completed

  12. get_tool_help

    Recorded tool call · completed

  13. Progress update

    I found the likely method: filter the supplied facility points to Country='Angola', compute a full geodesic point-to-cell-centre distance raster on the original WorldPop grid, build the selected-population raster with a ≤20 km test, then summarize both original and selected people per cell. I’m reading the exact processor contracts now so I don’t guess any parameter names.

  14. describe_processors

    Recorded tool call · failed

  15. describe_processors

    Recorded tool call · failed

  16. describe_processors

    Recorded tool call · completed

  17. describe_processors

    Recorded tool call · completed

  18. describe_processors

    Recorded tool call · completed

  19. describe_processors

    Recorded tool call · completed

  20. describe_processors

    Recorded tool call · completed

  21. get_tool_help

    Recorded tool call · completed

  22. get_tool_help

    Recorded tool call · failed

  23. get_tool_help

    Recorded tool call · completed

  24. Progress update

    I’ve got the core processor chain. The remaining uncertainty is the exact output wiring and whether the map-algebra expression preserves the original NoData mask while writing zeros outside the 20 km selection. I’m going to prove that on a small private trial before I scale it to all of Angola.

  25. update_analysis_brief

    Recorded tool call · completed

  26. describe_processors

    Recorded tool call · completed

  27. describe_processors

    Recorded tool call · completed

  28. run_trial

    Recorded tool call · completed

  29. Progress update

    The private full-area test succeeded. It already shows a non-empty Angola facility set, original-grid distance output in metres, and selected-population values with the original missing-data mask preserved. I’m doing a quick inspection of the filtered facilities and the preview images now, then I’ll save the exact tested method as the production workflow and run it.

  30. get_trial_report

    Recorded tool call · completed

  31. inspect_artifact

    Recorded tool call · completed

  32. Progress update

    The method is already proven on the full supplied Angola raster. Now I’m turning that exact tested computation into the publishable workflow, then I’ll inspect the final rasters and lock in the machine-readable answer from those final artifacts.

  33. inspect_artifact

    Recorded tool call · completed

  34. get_tool_help

    Recorded tool call · completed

  35. Progress update

    I’ve reached the workflow-save step. I’m reading the exact proposal schema now so the final published workflow uses the same tested nodes without any guesswork.

  36. get_tool_help

    Recorded tool call · completed

  37. get_tool_help

    Recorded tool call · completed

  38. get_tool_help

    Recorded tool call · completed

  39. get_tool_help

    Recorded tool call · completed

  40. get_tool_help

    Recorded tool call · completed

  41. get_tool_help

    Recorded tool call · completed

  42. get_tool_help

    Recorded tool call · completed

  43. get_tool_help

    Recorded tool call · completed

  44. get_tool_help

    Recorded tool call · completed

  45. get_tool_help

    Recorded tool call · completed

  46. Progress update

    I found one real limitation to carry forward: the filtered facilities file has 53 Angola points, but the full-grid distance run used 49 points. I’m checking that now against the supplied raster extent so the final answer clearly separates raster coverage from facility inventory coverage.

  47. inspect_artifact

    Recorded tool call · completed

  48. inspect_artifact

    Recorded tool call · completed

  49. inspect_artifact

    Recorded tool call · completed

  50. inspect_artifact

    Recorded tool call · completed

  51. Progress update

    I’m checking whether the 53 Angola facility records include duplicate coordinates. If they do, the 49-point distance count is still valid because duplicate original points don’t change the nearest-distance result or double count any raster cell.

  52. inspect_artifact

    Recorded tool call · completed

  53. Progress update

    The private test is enough to promote into the production workflow. It covered the full supplied Angola raster, not a local sample, and it showed that the 53 Angola facility records include 4 duplicate coordinate pairs, so the distance processor’s 49 effective point locations do not change the nearest-distance result.

  54. assess_trial

    Recorded tool call · completed

  55. Progress update

    I’ve finished the method development. I’m saving the exact tested full-area workflow now: same supplied inputs, same Country='Angola' filter, same geodesic cell-centre distance rule, and the two published rasters plus supporting summary tables.

  56. propose_workflow

    Recorded tool call · completed

  57. execute_workflow

    Recorded tool call · completed

  58. Progress update

    The workflow is validated and fully matches the tested computation. I’m running it now so the rasters are published as final inspectable outputs, then I’ll inspect those exact final artifacts and lock in the answer object.

  59. Progress update

    The final workflow run has finished in the background. I’m inspecting the exact published outputs now so the accepted answer is tied to the final rasters and final summary tables, not just the earlier trial.

  60. inspect_workflow_results

    Recorded tool call · completed

  61. Progress update

    I have the final published artifact identities. Next I’m collecting one bounded inspection for each final raster and summary table so the accepted answer points to the finished published outputs and their exact metrics.

  62. inspect_artifact

    Recorded tool call · completed

  63. inspect_artifact

    Recorded tool call · failed

  64. inspect_artifact

    Recorded tool call · completed

  65. inspect_artifact

    Recorded tool call · completed

  66. inspect_artifact

    Recorded tool call · failed

  67. Progress update

    I have the final output identities. I’m pulling the last two published summary tables and the final raster previews now, then I’ll record the answer object from those final published outputs.

  68. inspect_workflow_results

    Recorded tool call · completed

  69. inspect_artifact

    Recorded tool call · completed

  70. inspect_artifact

    Recorded tool call · completed

  71. Progress update

    I’ve got the final raster inspections. I’m pulling the three published summary tables directly by their final workflow node names now so the answer uses the final run’s own totals.

  72. inspect_artifact

    Recorded tool call · completed

  73. inspect_artifact

    Recorded tool call · completed

  74. inspect_artifact

    Recorded tool call · completed

  75. Progress update

    I’m finishing the last inspection receipts and then I can record the final answer. The numbers already match the verified full-area trial; this last step just binds them to the final published outputs.

  76. inspect_artifact

    Recorded tool call · completed

  77. inspect_artifact

    Recorded tool call · completed

  78. inspect_artifact

    Recorded tool call · completed

  79. Progress update

    I have everything needed for the final result now: the published selected-population raster, the published distance raster, and the published summary tables from the final run. I’m refreshing the brief notes so they match the completed evidence, then I’ll record the accepted answer object.

  80. update_analysis_brief

    Recorded tool call · completed

  81. inspect_artifact

    Recorded tool call · completed

  82. Progress update

    I’m adding one last check on the final run’s filtered facilities output so the accepted result is tied directly to the final Country='Angola' selection, not only the matching trial checksum.

  83. Progress update

    I have the final published rasters and tables. I’m collecting the final Angola-only facility receipt now, then I’ll record the accepted answer object against the finished outputs.

  84. inspect_artifact

    Recorded tool call · completed

  85. assess_result

    Recorded tool call · completed

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