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54 lines
1.6 KiB
Markdown
54 lines
1.6 KiB
Markdown
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---
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slug: /en/sql-reference/aggregate-functions/reference/cramersvbiascorrected
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sidebar_position: 352
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---
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# cramersVBiasCorrected
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Cramér's V is a measure of association between two columns in a table. The result of the [`cramersV` function](./cramersv) ranges from 0 (corresponding to no association between the variables) to 1 and can reach 1 only when each value is completely determined by the other. The function can be heavily biased, so this version of Cramér's V uses the [bias correction](https://en.wikipedia.org/wiki/Cram%C3%A9r%27s_V#Bias_correction).
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**Syntax**
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``` sql
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cramersVBiasCorrected(column1, column2)
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```
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**Arguments**
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- `column1` and `column2` are the columns to be compared
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**Returned value**
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- a value between 0 (corresponding to no association between the columns' values) to 1 (complete association).
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**Return type** is always [Float64](../../../sql-reference/data-types/float.md).
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**Example**
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The following two columns being compared below have a small association with each other. Notice the result of `cramersVBiasCorrected` is smaller than the result of `cramersV`:
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``` sql
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SELECT
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cramersV(a, b),
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cramersVBiasCorrected(a ,b)
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FROM
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(
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SELECT
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number % 10 AS a,
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number % 4 AS b
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FROM
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numbers(150)
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);
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```
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Result:
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```response
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┌──────cramersV(a, b)─┬─cramersVBiasCorrected(a, b)─┐
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│ 0.41171788506213564 │ 0.33369281784141364 │
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└─────────────────────┴─────────────────────────────┘
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```
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