window2.vl

{
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "data": {
        "url": "https://vega.github.io/vega-lite/data/movies.json"
    },
    "layer": [
        {
            "encoding": {
                "x": {
                    "axis": {
                        "title": "IMDB Rating"
                    },
                    "field": "IMDB_Rating",
                    "type": "quantitative"
                },
                "y": {
                    "field": "Title",
                    "type": "ordinal"
                }
            },
            "mark": "bar"
        },
        {
            "encoding": {
                "x": {
                    "aggregate": "mean",
                    "field": "AverageRating",
                    "type": "quantitative"
                }
            },
            "mark": {
                "color": "red",
                "type": "rule"
            }
        }
    ],
    "transform": [
        {
            "filter": "datum.IMDB_Rating != null"
        },
        {
            "frame": [
                null,
                null
            ],
            "window": [
                {
                    "as": "AverageRating",
                    "field": "IMDB_Rating",
                    "op": "mean"
                }
            ]
        },
        {
            "filter": "(datum.IMDB_Rating - datum.AverageRating) > 2.5"
        }
    ]
}