{
  "$schema": "urn:prism:schema:v1:spec",
  "title": "Score vs latency scatter",
  "data": {
    "name": "trials",
    "values": [
      {"latency_ms": 120, "score": 0.81, "group": "a"},
      {"latency_ms": 220, "score": 0.42, "group": "b"},
      {"latency_ms": 300, "score": 0.30, "group": "a"}
    ]
  },
  "mark": "point",
  "encoding": {
    "x":     {"field": "latency_ms", "type": "quantitative"},
    "y":     {"field": "score",      "type": "quantitative"},
    "color": {"field": "group",      "type": "nominal"}
  }
}