LAB 3 — ASSIGNMENT

Spatial Data Integration & Environmental Justice

Download the assignment file, complete the three questions, and submit your .qmd and rendered .html to Canvas.

Assignment Workflow

This file is identical to the tutorial
The pre-filled code (Steps 1–8) produces the same output as the tutorial. If this file is in the same folder as your tutorial QMD, you can knit immediately and see the same results. If you placed it in a different location, run the packages chunk first, then knit.
Need a Census API key?
Setup instructions are in the Lab 3 Tutorial under “Before You Begin.” Register free at api.census.gov/data/key_signup.html — key arrives by email within minutes.
1

Download and rename

Use the download link below. Save to your PAF516/Lab3/ folder. Rename to Lab3_Assignment_YourLastName.qmd before editing.

2

Knit the file first

Press Cmd+Shift+K (Mac) or Ctrl+Shift+K (PC). Steps 1–8 render automatically. Review the Step 7 distance-decay charts and the Step 8 buffer comparison — these are the results you will interpret for Q1 and Q3.

3

Answer the three questions

Q1: Interpret the distance-decay pattern and the environmental justice finding (text, 2 parts). Q2: Re-run the distance-decay analysis with finer distance bands by filling in the scaffold chunks at the end of the file (code). Q3: Compare the band patterns, interpret the multi-buffer UGCoP table, and make a policy recommendation (text, 3 parts). Re-knit after completing Q2.

4

Submit to Canvas

Submit both Lab3_Assignment_YourLastName.qmd and Lab3_Assignment_YourLastName.html.

The Three Questions

Q1 Interpret the Distance-Decay Pattern Text answer — no code required

After knitting, review the Step 7–8 charts and answer the following two parts:

  • Distance-decay: Describe the pattern in Step 7. Does mean hardship decrease as distance from facilities increases? Is the pattern strong or weak? Are there any unexpected reversals?
  • EJ interpretation: Do the maps and distance-decay chart support the environmental justice hypothesis — that lower-income communities bear disproportionate proximity to environmental hazards? Cite specific numbers from the decay table in your answer.

Replace the placeholder text in the Q1 section. A few sentences per bullet is sufficient.

Q2 Modify: Use Finer Distance Bands Code + output required

Re-run the Step 7 distance-decay analysis with finer distance bands: < 0.25 mi, 0.25–0.5 mi, 0.5–1 mi, 1–2 mi, > 2 mi.

  • Two scaffold chunks are provided at the end of the file: q2-fine-bands and q2-decay-plot
  • Copy the cbg_decay and decay_summary code from Step 7, then change the breaks in cut() to c(0, 0.25, 0.5, 1.0, 2.0, Inf) and update the labels
  • Regenerate the hardship and poverty decay bar charts using the new summary
Q3 Interpret Buffer Sensitivity (UGCoP) Text answer — no code required

Answer the following three parts:

  • Decay comparison: How does the finer-band pattern (Q2) compare to the original 5-band version (Step 7)? Did breaking < 0.5 mi into two sub-bands reveal anything new about the very nearest block groups?
  • UGCoP: Look at the multi-buffer comparison table from Step 8. Is the gap between inside and outside buffer consistent across the three distances (0.5, 1.0, 2.0 miles), or does it shrink or change at one threshold? What does this tell you about the Uncertain Geographic Context Problem?
  • Policy recommendation: If you were advising a city agency on which block groups to prioritize for environmental remediation funding, what buffer distance would you recommend — and why? Drawing on Kwan (2012) and Maantay (2002), how would you defend that choice?

Quick Reference

ActionMacPC
Run current chunkCmd+ReturnCtrl+Enter
Knit / RenderCmd+Shift+KCtrl+Shift+K

Download & Submit

Lab 3 Assignment File

Download Lab3_Assignment.qmd

Right-click → Save Link As. Save to your PAF516/Lab3/ folder.

Submit to Canvas

  • Lab3_Assignment_YourLastName.qmd — your edited source file
  • Lab3_Assignment_YourLastName.html — the rendered output