Statistics with R
- Statistics with R
- R Objects, Numbers, Attributes, Vectors, Coercion
- Matrices, Lists, Factors
- Data Frames in R
- Control Structures in R
- Functions in R
- Data Basics: Compute Summary Statistics in R
- Central Tendency and Spread in R Programming
- Data Basics: Plotting – Charts and Graphs
- Normal Distribution in R
- Skewness of statistical data
- Bernoulli Distribution in R
- Binomial Distribution in R Programming
- Compute Randomly Drawn Negative Binomial Density in R Programming
- Poisson Functions in R Programming
- How to Use the Multinomial Distribution in R
- Beta Distribution in R
- Chi-Square Distribution in R
- Exponential Distribution in R Programming
- Log Normal Distribution in R
- Continuous Uniform Distribution in R
- Understanding the t-distribution in R
- Gamma Distribution in R Programming
- How to Calculate Conditional Probability in R?
- How to Plot a Weibull Distribution in R
- Hypothesis Testing in R Programming
- T-Test in R Programming
- Type I Error in R
- Type II Error in R
- Confidence Intervals in R
- Covariance and Correlation in R
- Covariance Matrix in R
- Pearson Correlation in R
- Normal Probability Plot in R
Skewness of statistical data
Skewness is a measure of the asymmetry of a probability distribution. In R, you can calculate the skewness of a dataset using the skewness()
function from the e1071
package.
You can install the e1071
package in R using the install.packages()
function. Here’s an example:
# Install the e1071 package install.packages("e1071")
Here’s an example of how to calculate skewness using skewness()
# Load the e1071 package library(e1071) # Create a vector of data x <- c(1, 2, 3, 4, 5, 6, 7, 8, 9) # Calculate the skewness of the data skewness(x)
Skewness using the psych
package in R
You can use various statistical methods and visualizations to identify whether a distribution is skewed or not in R. Here are some steps that you can follow:
Install and Load the necessary R packages:
install.packages("ggplot2") install.packages("psych") library(ggplot2) # for creating visualizations library(psych) # for computing skewness
2. Generate a sample data set with a known distribution that you suspect is skewed. For example, we can create a sample data set from a normal distribution:
set.seed(123) # to ensure reproducibility x <- rnorm(1000, mean = 0, sd = 1)
3. Compute the skewness of the data using the skewness
function from the psych
package:
skewness(x)
4. Visualize the distribution using a histogram and a density plot using ggplot2
package:
ggplot(data.frame(x), aes(x=x)) + geom_histogram(bins=30, fill="lightblue", col="black") + geom_density(fill="red", alpha=0.3) + theme_classic()
Skewness using the moments
package
# Load the 'moments' package library(moments) # Generate some sample data x <- c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10) # Calculate the skewness of the data skewness(x)