Statistical Inference
Have you ever wondered how we can make a big claim from a small amount of data — like figuring out if one group of students gets more sleep than another? That's what statistical inference is all about.
In this subtopic, you'll learn how to compare two groups from a population using sample data. You’ll use tools like dot plots, box plots, and measures like median and IQR to make and justify conclusions — all part of a real statistical investigation.
This is the kind of thinking that helps businesses understand customers, health researchers test treatments, and scientists answer big questions using just a slice of the data.
Concepts
Work through each section to learn and practise the skills you'll need for a full statistical investigation. Each concept builds on the last, so it’s best to move through them in order.
Introduction
Overview of the standard, learning goals, and recommended resources.
Statistical Inference Basics
Understand the purpose of a statistical investigation, key concepts, and what it means to make an inference.
Writing Comparison Questions
Pose comparison questions that clearly identify the population and variable of interest.
Sampling & Data Collection
Understand sampling methods and how to collect appropriate data.
Plotting & Summarising Data
Use dot plots and box plots to summarise data using median, IQR, and shape.
Comparing Distributions
Compare groups using medians and IQRs. Identify overlap and variation.
Informal Confidence Intervals
Use the middle 50% of the data to make informal statements about population medians.
Making an Inference
Write a justified statistical conclusion in context, including comments on variability and uncertainty.
Summary & Revision
Review key ideas, practise skills, and prepare for the internal assessment.