Spearman rank correlation API

Computes Spearman's rho (rank correlation, tie-corrected) with a t-based significance test, capturing monotonic association robust to outliers and non-linearity. Answers 'What is the rank correlation between two variables?', 'Is the monotonic relationship significant?'.

Price$0.06per request

MethodPOST

Route/v1/stats/spearman-correlation

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

statisticscorrelationspearmanranknonparametricmonotonicsignificanceinference

API URLhttps://x402.hexl.dev/v1/stats/spearman-correlation

Integration docs

Example request

{
  "x": [
    1,
    2,
    3,
    4,
    5
  ],
  "y": [
    2,
    1,
    4,
    3,
    5
  ]
}

Example response

{
  "rho": 0.8,
  "n": 5,
  "df": 3,
  "t": 2.309401,
  "pValue": 0.104088,
  "alpha": 0.05,
  "direction": "positive",
  "rating": "very strong",
  "significant": false,
  "interpretation": "Spearman ρ=0.8 (very strong positive monotonic), p=0.1041."
}

Input schema

{
  "type": "object",
  "required": [
    "x",
    "y"
  ],
  "properties": {
    "x": {
      "type": "array",
      "items": {
        "type": "number"
      },
      "examples": [
        [
          1,
          2,
          3,
          4,
          5
        ]
      ]
    },
    "y": {
      "type": "array",
      "items": {
        "type": "number"
      },
      "examples": [
        [
          2,
          1,
          4,
          3,
          5
        ]
      ]
    },
    "alpha": {
      "type": "number",
      "examples": [
        0.05
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}