How to Calculate a Trimmed Mean in R

To calculate trimmed mean you can use mean() function with trim argument. A trimmed mean is the mean of a dataset that has been calculated after removing a specific percentage of the smallest and largest values from the dataset.

The following method shows how you can do it with syntax.

Method 1: Use mean() Function

mean(data,trim)

The following example shows how to calculate trimmed mean in R.

Use mean() To Calculate Trimmed Mean

Let’s see how we can calculate trimmed mean for one of the column of dataframe.

# Create dataframe
df <- data.frame(Machine_name=c("A","B","C","D","E","F","G","H"),
                 Pressure1=c(78.2, 28, 71.7, 80.21, 72.7, 30, 84.21, 76.2),
                 Temperature1=c(31, 33, 36, 37, 36, 33, 37, 31),
                 Status=c(TRUE,TRUE,FALSE,TRUE,FALSE,TRUE,TRUE,TRUE))

# Calculate trimmed mean
m <- mean(df$Pressure1,trim = 0.2)

# Display trimmed mean
print(m)

Output:

[1] 68.16833

The output shows trimmed mean for Pressure column of dataframe. Here we calculated 20% trimmed mean value for Pressure1 column of dataframe.

Use mean() To Calculate Trimmed Mean for Multiple Variables of Data Frame

Let’s apply mean() function to multiple columns of dataframe to calculate trimmed mean.

# Create dataframe
df <- data.frame(Machine_name=c("A","B","C","D","E","F","G","H"),
                 Pressure1=c(78.2, 28, 71.7, 80.21, 72.7, 30, 84.21, 76.2),
                 Temperature1=c(31, 33, 36, 37, 36, 33, 37, 31),
                 Status=c(TRUE,TRUE,FALSE,TRUE,FALSE,TRUE,TRUE,TRUE))

# Calculate trimmed mean
m <- sapply(df[c("Pressure1","Temperature1")],function(x) mean(x,trim = 0.1))

# Display trimmed mean
print(m)

Output:

 Pressure1 Temperature1 
     65.1525      34.2500 

Here the output shows trimmed mean for Pressure1 and Temperature1 column of dataframe.