# values_at: Calculate representative values of a vector In strengejacke/ggeffects: Create Tidy Data Frames of Marginal Effects for 'ggplot' from Model Outputs

 values_at R Documentation

## Calculate representative values of a vector

### Description

This function calculates representative values of a vector, like minimum/maximum values or lower, median and upper quartile etc., which can be used for numeric vectors to plot adjusted predictions at these representative values.

### Usage

``````values_at(x, values = "meansd")

representative_values(x, values = "meansd")
``````

### Arguments

 `x` A numeric vector. `values` Character vector, naming a pattern for which representative values should be calculcated. `⁠"minmax": ⁠`(default) minimum and maximum values (lower and upper bounds) of the moderator are used to plot the interaction between independent variable and moderator. `"meansd"`: uses the mean value of the moderator as well as one standard deviation below and above mean value to plot the effect of the moderator on the independent variable. `"zeromax"`: is similar to the `"minmax"` option, however, `0` is always used as minimum value for the moderator. This may be useful for predictors that don't have an empirical zero-value, but absence of moderation should be simulated by using 0 as minimum. `⁠"fivenum": ⁠`calculates and uses the Tukey's five number summary (minimum, lower-hinge, median, upper-hinge, maximum) of the moderator value. `"quart"`: calculates and uses the quartiles (lower, median and upper) of the moderator value, including minimum and maximum value. `"quart2"`: calculates and uses the quartiles (lower, median and upper) of the moderator value, excluding minimum and maximum value. `"terciles"`: calculates and uses the terciles (lower and upper third) of the moderator value, including minimum and maximum value. `"terciles2"`: calculates and uses the terciles (lower and upper third) of the moderator value, excluding minimum and maximum value. `"all"`: uses all values of the moderator variable. Note that this option only applies to `type = "eff"`, for numeric moderator values.

### Value

A numeric vector of length two or three, representing the required values from `x`, like minimum/maximum value or mean and +/- 1 SD. If `x` is missing, a function, pre-programmed with `n` and `length` is returned. See examples.

### Examples

``````data(efc)
values_at(efc\$c12hour)
values_at(efc\$c12hour, "quart2")

mean_sd <- values_at(values = "meansd")
mean_sd(efc\$c12hour)
``````

strengejacke/ggeffects documentation built on April 21, 2024, 9:30 a.m.