IQR {stats} | R Documentation |

## The Interquartile Range

### Description

computes interquartile range of the `x`

values.

### Usage

```
IQR(x, na.rm = FALSE, type = 7)
```

### Arguments

`x` |
a numeric vector. |

`na.rm` |
logical. Should missing values be removed? |

`type` |
an integer selecting one of the many quantile algorithms,
see |

### Details

Note that this function computes the quartiles using the
`quantile`

function rather than following
Tukey's recommendations,
i.e., `IQR(x) = quantile(x, 3/4) - quantile(x, 1/4)`

.

For normally `N(m,1)`

distributed `X`

, the expected value of
`IQR(X)`

is `2*qnorm(3/4) = 1.3490`

, i.e., for a normal-consistent
estimate of the standard deviation, use `IQR(x) / 1.349`

.

### References

Tukey, J. W. (1977).
*Exploratory Data Analysis.*
Reading: Addison-Wesley.

### See Also

`fivenum`

, `mad`

which is more robust,
`range`

, `quantile`

.

### Examples

```
IQR(rivers)
```

[Package

*stats*version 4.4.1 Index]