R Academy · Lesson

Time Series Analysis

Learn to analyze and forecast data collected over time, using autocorrelation and trend detection.

Lesson 2 of 310 steps

Time Series Analysis is a free R Academy lesson on CoddyKit. This is lesson 2 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 Time Series Analysis

Time series analysis is used to study data points collected over time, identifying trends, seasonality, and patterns.

Time Series Analysis — illustration 1

Loading Time Series Data

Use the ts() function to create a time series object in R.

data <- ts(c(100, 120, 130, 150, 170, 180), start=c(2020,1), frequency=12)
plot(data, main='Time Series Data')

Decomposing Time Series

The decompose() function splits time series into trend, seasonal, and random components.

decomposed <- decompose(data)
plot(decomposed)

Identifying Trends

Moving averages smooth fluctuations to reveal long-term trends.

library(zoo)
trend <- rollmean(data, k=3, fill=NA)
plot(data, type='l')
lines(trend, col='red', lwd=2)

Seasonality Detection

Seasonality refers to repeating patterns at fixed intervals.

plot(decomposed$seasonal, main='Seasonal Component')

Autocorrelation in Time Series

The acf() function measures correlations between past and present values.

acf(data, main='Autocorrelation Plot')

Forecasting with ARIMA

ARIMA (AutoRegressive Integrated Moving Average) is a popular time series forecasting model.

library(forecast)
model <- auto.arima(data)
forecasted <- forecast(model, h=5)
plot(forecasted)

Evaluating Forecast Accuracy

Use Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE) to measure forecast accuracy.

accuracy(forecasted)

Summary

In this lesson, you learned:

  • How to create and analyze time series data.
  • How to detect trends, seasonality, and autocorrelation.
  • How to forecast using ARIMA and evaluate predictions.
Time Series Analysis — illustration 10
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Frequently Asked Questions

Is the “Time Series Analysis” lesson free?

Yes — any 3 lessons of the R Academy learning path, including “Time Series Analysis”, 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 “Time Series Analysis”?

Learn to analyze and forecast data collected over time, using autocorrelation and trend detection. 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 2 of 3.

How long does the “Time Series Analysis” 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. Regression Models
  2. Time Series Analysis
  3. Machine Learning Fundamentals
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