Explore statistics over split data

The dataset viewer provides a /statistics endpoint for fetching some basic statistics precomputed for a requested dataset. This will get you a quick insight on how the data is distributed.

Currently, statistics are computed only for datasets with Parquet exports.

The /statistics endpoint requires three query parameters:

Let’s get some stats for nyu-mll/glue dataset, cola config, train split:

Python
JavaScript
cURL
import requests
headers = {"Authorization": f"Bearer {API_TOKEN}"}
API_URL = "https://datasets-server.huggingface.co/statistics?dataset=nyu-mll/glue&config=cola&split=train"
def query():
    response = requests.get(API_URL, headers=headers)
    return response.json()
data = query()

The response JSON contains three keys:

{
  "num_examples": 8551,
  "statistics": [
    {
      "column_name": "idx",
      "column_type": "int",
      "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0,
        "min": 0,
        "max": 8550,
        "mean": 4275,
        "median": 4275,
        "std": 2468.60541,
        "histogram": {
          "hist": [
            856,
            856,
            856,
            856,
            856,
            856,
            856,
            856,
            856,
            847
          ],
          "bin_edges": [
            0,
            856,
            1712,
            2568,
            3424,
            4280,
            5136,
            5992,
            6848,
            7704,
            8550
          ]
        }
      }
    },
    {
      "column_name": "label",
      "column_type": "class_label",
      "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0,
        "no_label_count": 0,
        "no_label_proportion": 0,
        "n_unique": 2,
        "frequencies": {
          "unacceptable": 2528,
          "acceptable": 6023
        }
      }
    },
    {
      "column_name": "sentence",
      "column_type": "string_text",
      "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0,
        "min": 6,
        "max": 231,
        "mean": 40.70074,
        "median": 37,
        "std": 19.14431,
        "histogram": {
          "hist": [
            2260,
            4512,
            1262,
            380,
            102,
            26,
            6,
            1,
            1,
            1
          ],
          "bin_edges": [
            6,
            29,
            52,
            75,
            98,
            121,
            144,
            167,
            190,
            213,
            231
          ]
        }
      }
    }
  ],
  "partial": false
}

Response structure by data type

Currently, statistics are supported for strings, float and integer numbers, lists, audio data and the special datasets.ClassLabel feature type of the datasets library.

column_type in response can be one of the following values:

class_label

This type represents categorical data encoded as ClassLabel feature. The following measures are computed:

Example

{
  "column_name": "label",
  "column_type": "class_label",
  "column_statistics": {
    "nan_count": 0,
    "nan_proportion": 0,
    "no_label_count": 0,
    "no_label_proportion": 0,
    "n_unique": 2,
    "frequencies": {
      "unacceptable": 2528,
      "acceptable": 6023
    }
  }
}

float

The following measures are returned for float data types:

Example

{
  "column_name": "clarity",
  "column_type": "float",
  "column_statistics": {
    "nan_count": 0,
    "nan_proportion": 0,
    "min": 0,
    "max": 2,
    "mean": 1.67206,
    "median": 1.8,
    "std": 0.38714,
    "histogram": {
      "hist": [
        17,
        12,
        48,
        52,
        135,
        188,
        814,
        15,
        1628,
        2048
      ],
      "bin_edges": [
        0,
        0.2,
        0.4,
        0.6,
        0.8,
        1,
        1.2,
        1.4,
        1.6,
        1.8,
        2
      ]
    }
  }
}

int

The following measures are returned for integer data types:

Example

{
    "column_name": "direction",
    "column_type": "int",
    "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0.0,
        "min": 0,
        "max": 1,
        "mean": 0.49925,
        "median": 0.0,
        "std": 0.5,
        "histogram": {
            "hist": [
                50075,
                49925
            ],
            "bin_edges": [
                0,
                1,
                1
            ]
        }
    }
}

bool

The following measures are returned for bool data type:

Example

{
  "column_name": "penalty",
  "column_type": "bool",
  "column_statistics":
    {
        "nan_count": 3,
        "nan_proportion": 0.15,
        "frequencies": {
            "False": 7,
            "True": 10
        }
    }
}

string_label

If the proportion of unique values in a string column within requested split is lower than or equal to 0.2 and the number of unique values is lower than 1000, or if the number of unique values is lower or equal to 10 (independently of the proportion), it is considered to be a category. The following measures are returned:

Example

{
  "column_name": "answerKey",
  "column_type": "string_label",
  "column_statistics": {
    "nan_count": 0,
    "nan_proportion": 0,
    "n_unique": 4,
    "frequencies": {
      "D": 1221,
      "C": 1146,
      "A": 1378,
      "B": 1212
    }
  }
}

string_text

If string column does not satisfy the conditions to be treated as a string_label, it is considered to be a column containing texts and response contains statistics over text lengths. The following measures are computed:

Example

{
  "column_name": "sentence",
  "column_type": "string_text",
  "column_statistics": {
    "nan_count": 0,
    "nan_proportion": 0,
    "min": 6,
    "max": 231,
    "mean": 40.70074,
    "median": 37,
    "std": 19.14431,
    "histogram": {
      "hist": [
        2260,
        4512,
        1262,
        380,
        102,
        26,
        6,
        1,
        1,
        1
      ],
      "bin_edges": [
        6,
        29,
        52,
        75,
        98,
        121,
        144,
        167,
        190,
        213,
        231
      ]
    }
  }
}

list

For lists, the distribution of their lengths is computed. The following measures are returned:

Example

{
    "column_name": "chat_history",
    "column_type": "list",
    "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0.0,
        "min": 1,
        "max": 3,
        "mean": 1.01741,
        "median": 1.0,
        "std": 0.13146,
        "histogram": {
            "hist": [
                11177,
                196,
                1
            ],
            "bin_edges": [
                1,
                2,
                3,
                3
            ]
        }
    }
}

Note that dictionaries of lists are not supported.

audio

For audio data, the distribution of audio files durations is computed. The following measures are returned:

Example

{
    "column_name": "audio",
    "column_type": "audio",
    "column_statistics": {
        "nan_count": 0,
        "nan_proportion": 0,
        "min": 1.02,
        "max": 15,
        "mean": 13.93042,
        "median": 14.77,
        "std": 2.63734,
        "histogram": {
            "hist": [
                32,
                25,
                18,
                24,
                22,
                17,
                18,
                19,
                55,
                1770
            ],
            "bin_edges": [
                1.02,
                2.418,
                3.816,
                5.214,
                6.612,
                8.01,
                9.408,
                10.806,
                12.204,
                13.602,
                15
            ]
        }
    }
}