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51 lines
1.4 KiB
Markdown
51 lines
1.4 KiB
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/contingency
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sidebar_position: 350
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---
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# contingency
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The `contingency` function calculates the [contingency coefficient](https://en.wikipedia.org/wiki/Contingency_table#Cram%C3%A9r's_V_and_the_contingency_coefficient_C), a value that measures the association between two columns in a table. The computation is similar to [the `cramersV` function](./cramersv) but with a different denominator in the square root.
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**Syntax**
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``` sql
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contingency(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 to 1. The larger the result, the closer the association of the two columns.
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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 two columns being compared below have a small association with each other. We have included the result of `cramersV` also (as a comparison):
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``` sql
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SELECT
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cramersV(a, b),
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contingency(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)─┬───contingency(a, b)─┐
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│ 0.41171788506213564 │ 0.05812725261759165 │
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└─────────────────────┴─────────────────────┘
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``` |