{
  "alt": "Five small dot plots, one for each measure, each with four dots for grades A to D. In the first view the dot for grade A sits at zero and the dots for grades B, C and D move to the right for traffic, NO₂, diesel PM and the stacked score, with small differences for PM₂.₅. In the second view the dots show pooled grade means, which are further apart for traffic, NO₂ and diesel PM.",
  "caption": "Within a county, dots move right from grade A, the baseline at zero, to grade D for every measure, and the PM₂.₅ differences are the smallest. The second view shows the grade means pooled across all graded tracts, where the traffic percentile goes from {fact:redline_ptraf_a} in grade A to {fact:redline_ptraf_d} in grade D, larger gaps that also reflect differences between the cities that were graded. Whiskers are 95% intervals from a bootstrap over counties. Each tract takes the 1930s grade that covers most of its area, and tracts are kept when graded areas cover at least {fact:holc_cover_min} of them.",
  "data": [
    {
      "conf_high": null,
      "conf_low": null,
      "contrast": "within",
      "estimate": 0,
      "grade": "A",
      "label": "Grade A",
      "measure": "Traffic proximity (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 1.78,
      "conf_low": -0.18,
      "contrast": "within",
      "estimate": 0.81,
      "grade": "B",
      "label": "Grade B",
      "measure": "Traffic proximity (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 3.15,
      "conf_low": 0.86,
      "contrast": "within",
      "estimate": 2.06,
      "grade": "C",
      "label": "Grade C",
      "measure": "Traffic proximity (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 5.12,
      "conf_low": 2.67,
      "contrast": "within",
      "estimate": 3.91,
      "grade": "D",
      "label": "Grade D",
      "measure": "Traffic proximity (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": 80.28,
      "conf_low": 74.52,
      "contrast": "pooled",
      "estimate": 77.55,
      "grade": "A",
      "label": "Grade A",
      "measure": "Traffic proximity (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 84.21,
      "conf_low": 78.81,
      "contrast": "pooled",
      "estimate": 81.74,
      "grade": "B",
      "label": "Grade B",
      "measure": "Traffic proximity (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 87.02,
      "conf_low": 80.11,
      "contrast": "pooled",
      "estimate": 84.16,
      "grade": "C",
      "label": "Grade C",
      "measure": "Traffic proximity (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 88.62,
      "conf_low": 82.79,
      "contrast": "pooled",
      "estimate": 86.34,
      "grade": "D",
      "label": "Grade D",
      "measure": "Traffic proximity (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": null,
      "conf_low": null,
      "contrast": "within",
      "estimate": 0,
      "grade": "A",
      "label": "Grade A",
      "measure": "NO₂ (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 6.41,
      "conf_low": 2.47,
      "contrast": "within",
      "estimate": 4.46,
      "grade": "B",
      "label": "Grade B",
      "measure": "NO₂ (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 8.76,
      "conf_low": 4.48,
      "contrast": "within",
      "estimate": 6.67,
      "grade": "C",
      "label": "Grade C",
      "measure": "NO₂ (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 12.2,
      "conf_low": 7.23,
      "contrast": "within",
      "estimate": 9.74,
      "grade": "D",
      "label": "Grade D",
      "measure": "NO₂ (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": 76.36,
      "conf_low": 69.73,
      "contrast": "pooled",
      "estimate": 73.03,
      "grade": "A",
      "label": "Grade A",
      "measure": "NO₂ (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 81.99,
      "conf_low": 74.96,
      "contrast": "pooled",
      "estimate": 78.72,
      "grade": "B",
      "label": "Grade B",
      "measure": "NO₂ (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 85.72,
      "conf_low": 79.03,
      "contrast": "pooled",
      "estimate": 82.73,
      "grade": "C",
      "label": "Grade C",
      "measure": "NO₂ (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 89.21,
      "conf_low": 82.52,
      "contrast": "pooled",
      "estimate": 86.36,
      "grade": "D",
      "label": "Grade D",
      "measure": "NO₂ (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": null,
      "conf_low": null,
      "contrast": "within",
      "estimate": 0,
      "grade": "A",
      "label": "Grade A",
      "measure": "Diesel PM (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 2.19,
      "conf_low": 0.24,
      "contrast": "within",
      "estimate": 1.24,
      "grade": "B",
      "label": "Grade B",
      "measure": "Diesel PM (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 3.57,
      "conf_low": 1.71,
      "contrast": "within",
      "estimate": 2.7,
      "grade": "C",
      "label": "Grade C",
      "measure": "Diesel PM (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 6.45,
      "conf_low": 3.92,
      "contrast": "within",
      "estimate": 5.14,
      "grade": "D",
      "label": "Grade D",
      "measure": "Diesel PM (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": 76.57,
      "conf_low": 68.93,
      "contrast": "pooled",
      "estimate": 73.05,
      "grade": "A",
      "label": "Grade A",
      "measure": "Diesel PM (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 81.66,
      "conf_low": 72.33,
      "contrast": "pooled",
      "estimate": 77.41,
      "grade": "B",
      "label": "Grade B",
      "measure": "Diesel PM (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 84.97,
      "conf_low": 75.26,
      "contrast": "pooled",
      "estimate": 81.17,
      "grade": "C",
      "label": "Grade C",
      "measure": "Diesel PM (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 89.44,
      "conf_low": 80.5,
      "contrast": "pooled",
      "estimate": 86.02,
      "grade": "D",
      "label": "Grade D",
      "measure": "Diesel PM (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": null,
      "conf_low": null,
      "contrast": "within",
      "estimate": 0,
      "grade": "A",
      "label": "Grade A",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 0.88,
      "conf_low": -0.01,
      "contrast": "within",
      "estimate": 0.42,
      "grade": "B",
      "label": "Grade B",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 1.28,
      "conf_low": 0.03,
      "contrast": "within",
      "estimate": 0.67,
      "grade": "C",
      "label": "Grade C",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 2.02,
      "conf_low": 0.25,
      "contrast": "within",
      "estimate": 1.13,
      "grade": "D",
      "label": "Grade D",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": 62.68,
      "conf_low": 49.05,
      "contrast": "pooled",
      "estimate": 55.85,
      "grade": "A",
      "label": "Grade A",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 672
    },
    {
      "conf_high": 61.24,
      "conf_low": 47.08,
      "contrast": "pooled",
      "estimate": 54.02,
      "grade": "B",
      "label": "Grade B",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 2246
    },
    {
      "conf_high": 68.58,
      "conf_low": 46.88,
      "contrast": "pooled",
      "estimate": 58.11,
      "grade": "C",
      "label": "Grade C",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 5054
    },
    {
      "conf_high": 69.39,
      "conf_low": 51.02,
      "contrast": "pooled",
      "estimate": 60.02,
      "grade": "D",
      "label": "Grade D",
      "measure": "PM₂.₅ (percentile)",
      "n_units": 2978
    },
    {
      "conf_high": null,
      "conf_low": null,
      "contrast": "within",
      "estimate": 0,
      "grade": "A",
      "label": "Grade A",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 672
    },
    {
      "conf_high": 0.34,
      "conf_low": 0.05,
      "contrast": "within",
      "estimate": 0.2,
      "grade": "B",
      "label": "Grade B",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 2246
    },
    {
      "conf_high": 0.5,
      "conf_low": 0.24,
      "contrast": "within",
      "estimate": 0.38,
      "grade": "C",
      "label": "Grade C",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 5054
    },
    {
      "conf_high": 0.72,
      "conf_low": 0.42,
      "contrast": "within",
      "estimate": 0.58,
      "grade": "D",
      "label": "Grade D",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 2978
    },
    {
      "conf_high": 2.52,
      "conf_low": 2.04,
      "contrast": "pooled",
      "estimate": 2.29,
      "grade": "A",
      "label": "Grade A",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 672
    },
    {
      "conf_high": 2.87,
      "conf_low": 2.29,
      "contrast": "pooled",
      "estimate": 2.6,
      "grade": "B",
      "label": "Grade B",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 2246
    },
    {
      "conf_high": 3.35,
      "conf_low": 2.57,
      "contrast": "pooled",
      "estimate": 3,
      "grade": "C",
      "label": "Grade C",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 5054
    },
    {
      "conf_high": 3.5,
      "conf_low": 2.85,
      "contrast": "pooled",
      "estimate": 3.19,
      "grade": "D",
      "label": "Grade D",
      "measure": "Stacked air hazards (0 to 5)",
      "n_units": 2978
    }
  ],
  "id": "air_by_holc_grade",
  "notes": [
    "Differences in the first view come from a population-weighted regression of the tract value on grade with county fixed effects, so only counties that hold more than one grade inform them. Grade A is the baseline and has no interval. The pooled view compares tracts across {fact:redline_counties} counties.",
    "The HOLC maps cover the dense urban cores of cities, so even grade A tracts sit above the national median for traffic and NO₂. The comparison is among graded tracts and does not compare graded with ungraded places.",
    "A tract graded D today holds residents of today and not those of the 1930s. Grades A to D follow the original map labels, and areas graded E or F or left blank are set aside. Other outcomes by grade, including the Area Deprivation Index, are in the chapter on home value, income and redlining."
  ],
  "source": "Mapping Inequality HOLC maps (1935-1940) matched to 2020 tracts, EPA EJScreen 2024 and ACS 2019-2023; population-weighted means, modeled estimates",
  "spec": {
    "colors": {
      "A": "holcA",
      "B": "holcB",
      "C": "holcC",
      "D": "holcD"
    },
    "facet": "measure",
    "facetColumns": 3,
    "group": "grade",
    "hi": "conf_high",
    "legend": false,
    "lo": "conf_low",
    "sort": "data",
    "valueLabels": true,
    "x": "estimate",
    "xDomain": [
      -2,
      14
    ],
    "xDomains": {
      "Stacked air hazards (0 to 5)": [
        -0.2,
        1
      ]
    },
    "xFormat": {
      "digits": 1
    },
    "xLabel": "Difference from grade A in the same county (units named in each panel title)",
    "y": "label"
  },
  "subtitle": "Difference from grade A in the same county in the mean national percentile of four air indicators and in the mean stacked-hazard score, by dominant HOLC grade of the tract, population-weighted",
  "title": "Within the same county, tracts graded D in the 1930s rank {fact:redline_fe_ptraf} points above grade A tracts on the traffic percentile and {fact:redline_fe_no2} points on NO₂, and the stacked-hazard score is {fact:redline_fe_stack} higher",
  "type": "dot",
  "views": [
    {
      "filter": {
        "contrast": "within"
      },
      "id": "within",
      "label": "Within the same county"
    },
    {
      "filter": {
        "contrast": "pooled"
      },
      "id": "pooled",
      "label": "All graded tracts, pooled",
      "spec": {
        "xDomain": [
          0,
          100
        ],
        "xDomains": {
          "Stacked air hazards (0 to 5)": [
            0,
            5
          ]
        },
        "xLabel": "Mean value (units named in each panel title)"
      }
    }
  ]
}