Category: R

This tutorial shows how you can write R code for serial mediation. Unless you use Hayes’ R code, I am not aware how you can do serial mediation in R. Thus, I am providing this R code here for your...

This tutorial shows how to simulate a dataset for Poisson regression in R. Step 1: Determine the model Suppose that the following is the model with known population parameters, namely known regression coefficients of 0.2 and 0.08. Of course, in...

This tutorial explains how to write code for boostrapping mediation analysis in R from scratch. Mediation analysis is often used in academic research to understand the underlying mechanism. Often, you also need to report a bootstrapping confidence interval for the...

This tutorial is to show how to do logistic regression in R with examples. The following is the key syntax for logistic regression in R. glm(Y~ X1 + X2, data = data_frame_name, family = "binomial") Steps of logistic regression in...

This tutorial shows how you can convert dataframe columns to vectors in R with examples. The following shows the two methods to do it. Method 1: vector<-df$column Method 2: vector<-df[ , ‘column’] Examples of Convert Dataframe columns to Vectors in...

This tutorial shows how you can two sample t-test in R. Note that, Two sample t-test is also called independent sample t-test or unpaired sample t-test.  Method 1: Vector format t.test(vector_1, vector_2, var.equal = TRUE) Method 2: Data frame format...

This tutorial explains how you can do Johnson Neyman in R. You can use the package of “interactions” in R do Johnson Neyman in R. The following is the key R syntax. library(interactions) model <- lm(Y ~ X * M,...

This tutorial explains how to set and understand lower.tail in qnorm() and pnorm(). qnorm(p, mean, sd, lower.tail = TRUE, log.p = FALSE) pnorm(q, mean, sd, lower.tail = TRUE, log.p = FALSE) For both qnorm and pnorm, the meaning of lower.tail...

This tutorial explains how you can use qnorm() in R with examples. qnorm(p, mean = 0, sd = 1, lower.tail = TRUE, log.p = FALSE) p: the probability. mean: The mean of the normal distribution sample data. The default value is 0. sd: The...