{
  "alt": "Table with seven rows, one for each comparison in the chapter, and columns for the counties, elections, weights and the variables held fixed. The first four rows use the same counties in each election and both weightings.",
  "caption": "Each row names a comparison, the counties it uses, the elections it covers, its weights and the variables it holds fixed. The counties are identical across the first four rows within an election, so a change from one row to the next comes from the variables held fixed and not from a different set of counties. Both weightings are computed for every row.",
  "data": [
    {
      "comparison": "Correlation of one axis with the margin",
      "counties": "Counties with returns and every census measure; the same counties for every comparison in an election",
      "elections": "Each presidential election, 2000 to 2024",
      "held_fixed": "Nothing else",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "Regression of the margin on the five axes",
      "counties": "Same counties",
      "elections": "Each election, 2000 to 2024",
      "held_fixed": "The other four axes",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "The same regression with state baselines",
      "counties": "Same counties",
      "elections": "Each election, 2000 to 2024",
      "held_fixed": "The other four axes and a baseline margin for each state",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "Share of the variance of the margin reproduced (R-squared)",
      "counties": "Same counties",
      "elections": "Each election, 2000 to 2024",
      "held_fixed": "Five axes; five axes with state baselines; state baselines alone; nine measures",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "Checks with fixed census measures",
      "counties": "Counties that also have the fixed measures, a few fewer",
      "elections": "Each election, 2000 to 2024",
      "held_fixed": "The 2024 census measures, or the 2000 census measures, used for every election",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "Alternative measures within each axis",
      "counties": "The 2024 counties of the main sample",
      "elections": "2024",
      "held_fixed": "Nothing else",
      "weights": "Vote-weighted and county-equal"
    },
    {
      "comparison": "Map of the gap between margin and fit",
      "counties": "The 2000 and 2024 counties of the main sample",
      "elections": "2000 and 2024",
      "held_fixed": "The five axes",
      "weights": "Fit weighted by two-party votes"
    }
  ],
  "id": "comparisons",
  "source": "County presidential returns, 2000-2024 (Algara and Amlani; MIT Election Data and Science Lab), full counts of votes; county demographics panel (census and American Community Survey); both weightings reported",
  "spec": {
    "columns": [
      {
        "key": "comparison",
        "label": "Comparison"
      },
      {
        "key": "counties",
        "label": "Counties"
      },
      {
        "key": "elections",
        "label": "Elections"
      },
      {
        "key": "weights",
        "label": "Weights"
      },
      {
        "key": "held_fixed",
        "label": "Other variables held fixed"
      }
    ]
  },
  "subtitle": "The outcome, sample, period, weights and other variables of each comparison; the outcome is the county two-party margin, Democratic minus Republican",
  "title": "Every comparison in the chapter uses the same outcome and the same counties within an election, and differs in what it holds fixed",
  "type": "table",
  "width": "wide"
}