bland-altman sketch

bland-altman-sketch.json

{
  "$schema": "https://vega.github.io/schema/vega-lite/v6.json",
  "data": {"url": "data/anscombe.json"},
  "transform": [
    {"calculate": "datum.X - datum.Y", "as": "diff"},
    {"calculate": "(datum.X + datum.Y) / 2", "as": "avg"}
  ],
  "layer": [
    {
      "mark": "point",
      "encoding": {
        "x": {"field": "avg", "type": "quantitative"},
        "y": {"field": "diff", "type": "quantitative"}
      }
    },
    {
      "mark": "rule",
      "encoding": {"y": {"aggregate": "average", "field": "diff"}}
    },
    {
      "mark": "rule",
      "transform": [
        {
          "aggregate": [
            {"op": "mean", "field": "diff", "as": "mean_X"},
            {"op": "stdev", "field": "diff", "as": "std_X"}
          ]
        },
        {"calculate": "datum.mean_X + 1.96 * datum.std_X", "as": "std_calv"}
      ],
      "encoding": {"y": {"field": "std_calv", "type": "quantitative"}}
    },
    {
      "mark": "rule",
      "transform": [
        {
          "aggregate": [
            {"op": "mean", "field": "diff", "as": "mean_X"},
            {"op": "stdev", "field": "diff", "as": "std_X"}
          ]
        },
        {"calculate": "datum.mean_X - 1.96 * datum.std_X", "as": "std_calv"}
      ],
      "encoding": {"y": {"field": "std_calv", "type": "quantitative"}}
    }
  ]
}