seWithin is used to compute the standard error(s) for one or more variables, for one or more groups in a dataframe, handling within-subjects variables by removing inter-subject variability

seWithin(data = NULL, measurevar, betweenvars = NULL, withinvars = NULL,
idvar = NULL, na.rm = TRUE, conf.interval = 0.95, shownormed = FALSE)

## Arguments

data |
a dataframe |

measurevar |
the name(s) of column(s) that contain the variable to be summariezed |

betweenvars |
a vector containing names of columns that are between-subjects variables |

withinvars |
a vector containing names of columns that are within-subjects variables |

idvar |
the name of the column that identifies each subject |

na.rm |
boolean that indicates whether to ignore NA's |

conf.interval |
confidence interval range |

shownormed |
whether to show noramlized results |

## Value

A data.table

## Note

Code adapted from R cookbook (see references).

## References

http://www.cookbook-r.com/Graphs/Plotting_means_and_error_bars_(ggplot2)/

## See also

## Author

Hause Lin

## Examples

result <- seWithin(data = ChickWeight, measurevar = "weight",
betweenvars = "Diet", withinvars = "Time", idvar = "Chick")

#> Automatically converting the following non-factors to factors: Time

#> Joining, by = c("Chick", "Diet")

#> Joining, by = c("Diet", "Time", "N")

#> Factors have been converted to characters.

#> Confidence intervals: 0.95

#>

#> Automatically converting the following non-factors to factors: Time

#> Joining, by = c("Chick", "Diet")

#> Joining, by = c("Diet", "Time", "N")

#> Factors have been converted to characters.

#> Confidence intervals: 0.95

#>

#> Joining, by = c("Chick", "Diet")

#> Joining, by = c("Diet", "Time", "N")

#> Factors have been converted to characters.

#> Confidence intervals: 0.95

#>