scatter.smooth {stats} | R Documentation |

## Scatter Plot with Smooth Curve Fitted by Loess

### Description

Plot and add a smooth curve computed by `loess`

to a scatter plot.

### Usage

scatter.smooth(x, y = NULL, span = 2/3, degree = 1,
family = c("symmetric", "gaussian"),
xlab = NULL, ylab = NULL,
ylim = range(y, prediction$y, na.rm = TRUE),
evaluation = 50, ...)
loess.smooth(x, y, span = 2/3, degree = 1,
family = c("symmetric", "gaussian"), evaluation = 50, ...)

### Arguments

`x,y` |
the `x` and `y` arguments provide the x and y
coordinates for the plot. Any reasonable way of defining the
coordinates is acceptable. See the function `xy.coords`
for details. |

`span` |
smoothness parameter for `loess` . |

`degree` |
degree of local polynomial used. |

`family` |
if `"gaussian"` fitting is by least-squares, and if
`family="symmetric"` a re-descending M estimator is used. |

`xlab` |
label for x axis. |

`ylab` |
label for y axis. |

`ylim` |
the y limits of the plot. |

`evaluation` |
number of points at which to evaluate the smooth
curve. |

`...` |
graphical parameters. |

### Details

`loess.smooth`

is an auxiliary function which evaluates the
`loess`

smooth at `evaluation`

equally spaced points
covering the range of `x`

.

### Value

For `scatter.smooth`

, none.

For `loess.smooth`

, a list with two components, `x`

(the
grid of evaluation points) and `y`

(the smoothed values at the
grid points).

### See Also

`loess`

### Examples

attach(cars)
scatter.smooth(speed, dist)
detach()

[Package

*stats* version 2.2.1

Index]