R Academy · Lesson

Descriptive Statistics

Use R’s built-in functions to measure central tendencies and variability in datasets.

Lesson 1 of 310 steps

Descriptive Statistics is a free R Academy lesson on CoddyKit. This is lesson 1 of 3. Any 3 lessons of this learning path are free to read in full — after that, CoddyKit PRO unlocks every lesson, plus hands-on practice with a built-in code editor and a 24/7 AI tutor. It is part of the R Academy learning path, and your progress syncs across the web and the CoddyKit app. The R Academy course includes 3 lessons in total.

Introduction to Descriptive Statistics

Descriptive statistics summarize and describe features of a dataset. They provide insights into the data distribution and variability.

Descriptive Statistics — illustration 1

Calculating Mean

The mean (average) is calculated using the mean() function.

data <- c(10, 20, 30, 40, 50)
mean(data)

Calculating Median

The median is the middle value in a sorted dataset.

median(data)

Calculating Mode

R does not have a built-in mode function, but you can compute it manually.

mode_function <- function(x) {
  uniq_x <- unique(x)
  uniq_x[which.max(tabulate(match(x, uniq_x)))]
}
mode_function(data)

Calculating Standard Deviation

The standard deviation measures the spread of data points.

sd(data)

Calculating Variance

The variance quantifies the dispersion of data points.

var(data)

Calculating Summary Statistics

The summary() function provides an overview of descriptive statistics.

summary(data)

Calculating Quantiles

Use quantile() to find quartiles and percentiles in a dataset.

quantile(data, probs = c(0.25, 0.5, 0.75))

Summary

In this lesson, you learned:

  • How to calculate mean, median, and mode.
  • How to compute standard deviation and variance.
  • How to use summary() and quantile() for deeper insights.
Descriptive Statistics — illustration 10
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Frequently Asked Questions

Is the “Descriptive Statistics” lesson free?

Yes — any 3 lessons of the R Academy learning path, including “Descriptive Statistics”, are free to read in full here on the web. After that, CoddyKit PRO unlocks every lesson, plus interactive practice with a built-in code editor and a 24/7 AI tutor. The R Academy course includes 3 lessons in total.

What will I learn in “Descriptive Statistics”?

Use R’s built-in functions to measure central tendencies and variability in datasets. You practise R Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start R Academy?

No prior experience is required. R Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 1 of 3.

How long does the “Descriptive Statistics” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this R Academy lesson?

Yes. Every R Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

All lessons in this course

  1. Descriptive Statistics
  2. Probability Distributions
  3. Hypothesis Testing
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