simple_slopes_analysis: Simple slopes analysis

In kim: A Toolkit for Behavioral Scientists

Simple slopes analysis

Description

Conduct a simple slopes analysis, typically to probe a two-way interaction. (This function was edited with ChatGPT on Dec 13, 2025.)

Usage

simple_slopes_analysis(
  data = NULL,
  iv_name = NULL,
  dv_name = NULL,
  mod_name = NULL,
  round_focal_value = 2,
  round_b = 2,
  round_se = 2,
  round_t = 2,
  round_p = 3,
  focal_values = NULL
)

Arguments

data	a data object (a data frame or a data.table)
iv_name	name of the independent variable (IV)
dv_name	name of the dependent variable (DV)
mod_name	name of the moderator variable (MOD)
round_focal_value	number of decimal places to which to round the focal values (default = 2)
round_b	number of decimal places to which to round coefficients from the regression analysis (default = 2)
round_se	number of decimal places to which to round standard error values from the regression analysis (default = 2)
round_t	number of decimal places to which to round t statistics from the regression analysis (default = 2)
round_p	number of decimal places to which to round p values from the regression analysis (default = 2)
focal_values	this input will be used only in cases where moderator is continuous. In such cases, what are the focal values of the moderator at which to estimate the effect of IV on DV? By default, values corresponding to the mean of MOD, and mean of MOD +/-1 SD will be used.

Examples

simple_slopes_analysis(
data = mtcars, iv_name = "vs", dv_name = "mpg", mod_name = "am")
simple_slopes_analysis(
data = mtcars, iv_name = "vs", dv_name = "mpg", mod_name = "hp")
simple_slopes_analysis(
data = mtcars, iv_name = "disp", dv_name = "mpg", mod_name = "hp")
simple_slopes_analysis(
data = mtcars, iv_name = "vs", dv_name = "am", mod_name = "hp")
simple_slopes_analysis(
data = mtcars, iv_name = "disp", dv_name = "am", mod_name = "hp")
# when the iv is a factor
simple_slopes_analysis(
data = ToothGrowth, iv_name = "supp", dv_name = "len", mod_name = "dose")
# from the example above, switch the iv and moderator
simple_slopes_analysis(
data = ToothGrowth, iv_name = "dose", dv_name = "len", mod_name = "supp")

kim documentation built on Jan. 12, 2026, 5:08 p.m.