# Rarity Score (TF-IDF)

Term Frequency-Inverse Document Frequency(TF-IDF), is a numerical statistic that reflects the importance of a term within a document in a corpus. It is the default score for matched terms.

**Example:**

{% code lineNumbers="true" %}

```python
{
  "query": {
    "bool": {
      "must": 
        {
          "term": {
            "Color": "Black"
         }
      }
    }
  }
}
```

{% endcode %}

In the above example, matched documents will be assigned with a score based on the TF-IDF formula and will be ranked accordingly.


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