plot_effect: plotting the marginal effect of X on Y, with or without one...

In regrrr: Toolkit for Compiling, (Post-Hoc) Testing, and Plotting Regression Results

Description

plotting the marginal effect of X on Y, with or without one or multiple interaction terms

Usage

plot_effect(
  reg.coef,
  data,
  model,
  by_color = FALSE,
  x_var.name = NULL,
  y_var.name = NULL,
  moderator.name = NULL,
  min_x = 0.001,
  max_x = 0.999,
  mdrt_quantile_05 = NULL,
  mdrt_quantile_50 = NULL,
  mdrt_quantile_95 = NULL,
  mod.n.sd = 1,
  confidence_interval = FALSE,
  v = NULL,
  CI_Ribbon = FALSE,
  title = NULL,
  xlab = "X_Var.name",
  ylab = "Y_Var.name",
  moderator.lab = "Moderator_name",
  mdrt.low.name = "Low",
  mdrt.mid.name = NULL,
  mdrt.high.name = "High",
  y.high.lim = NULL,
  y.low.lim = NULL,
  spline_labels = c("LHS", "RHS")
)

Arguments

reg.coef	a coefficient matrix of regression result, e.g. summary(lm_model)$coef
data	the data used in regression, a data frame
model	the model object, such as a "lm" object
by_color	plot interactions by colors, otherwise by line types
x_var.name	x name in the regression model, a string
y_var.name	y name in the regression model, a string
moderator.name	moderating variable name in the regression model, a string
min_x	the min of x scale, in percentile of x
max_x	the max of x scale, in percentile of x
mdrt_quantile_05	set the low level of moderator, in percentile
mdrt_quantile_50	set the middle level of moderator, in percentile
mdrt_quantile_95	set the high level of moderator, in percentile
mod.n.sd	set the moderating strength, in the number of s.d. units, which can take negative values
confidence_interval	if TRUE, plot confidence intervals
v	a customized variance-covariance matrix
CI_Ribbon	if TRUE, plot confidence interval ribbons, if FALSE, plot error bars
title	the title of the plot
xlab	label of X
ylab	label of Y
moderator.lab	label of moderator
mdrt.low.name	the label of low-level moderator
mdrt.mid.name	the label of mid-level moderator
mdrt.high.name	the label of high-level moderator
y.high.lim	specify the upper limit of y
y.low.lim	specify the lower limit of y
spline_labels	label of the spline variable; when the main varaible is a linear spline and spline labels are supplied, the moderation effect will be presented by facets.

Examples

## Not run: 
data(mtcars)
m1 <- lm(mpg ~ vs + carb + hp + wt + wt * hp , data = mtcars)
plot_effect(reg.coef = summary(m1)$coefficients,
                 data = mtcars, model = m1,
                 x_var.name = "wt", y_var.name = "mpg", moderator.name = "hp",
                 confidence_interval = TRUE,  CI_Ribbon = TRUE,
                 xlab = "Weight", ylab = "MPG", moderator.lab = "Horsepower")

## End(Not run)

#' @examples
## Not run: 
data(mtcars)
m2 <- lm(mpg ~ vs + carb + hp + wt + wt * hp + wt * vs, data = mtcars)
plot_effect(reg.coef = summary(m2)$coefficients,
            data = mtcars, model = m2,
            x_var.name = "wt", y_var.name = "mpg", moderator.name = "hp",
            confidence_interval = TRUE,  CI_Ribbon = FALSE,
            xlab = "Weight", ylab = "MPG", moderator.lab = "Horsepower")

## End(Not run)

#' @examples
## Not run: 
data(mtcars)
m3 <- lm(mpg ~ vs + carb + hp + lspline(wt, knots = 4, marginal = FALSE) * hp, data = mtcars)
plot_effect(reg.coef=summary(m3)$coefficients, 
            data = mtcars, model = m3, x_var.name = "wt", y_var.name = "mpg", moderator.name = "hp",
            xlab="Weight", ylab="MPG", moderator.lab="Horsepower") 

## End(Not run)

## Not run: 
# this shows the function is compatible with ggplot2 customization
library(extrafont)
m1 <- lm(mpg ~ vs + carb + hp + wt + wt * hp , data = mtcars)
plot_effect(reg.coef = summary(m1)$coefficients, 
                 data = mtcars, model = m1, 
                 x_var.name = "wt", y_var.name = "mpg", moderator.name = "hp", 
                 confidence_interval = TRUE,  CI_Ribbon = TRUE, 
                 xlab = "Weight", ylab = "MPG", moderator.lab = "Horsepower") + 
ggplot2::theme(text=ggplot2::element_text(family="Times New Roman", size = 16))

## End(Not run)

regrrr documentation built on Aug. 13, 2021, 5:07 p.m.