This worksheet introduces the full statistical investigation cycle, teaching students to analyse data, report findings, and judge the strength of evidence behind a conclusion. The worksheet is split into warm-up questions, standard questions and then extension questions to test you.
The concepts it covers:
- A statistical investigation follows stages: pose a question, plan data collection, collect and analyse data, then report findings and conclusions.
- Data can be categorical (named groups, e.g. yes/no) or numerical (measured quantities, e.g. scores) — an investigation often needs both.
- "Strength of evidence" depends on sample size, sampling method, and whether the study design can support a causal claim (or only a correlational one).
- A correlation between two variables does not prove one causes the other — a confounding variable might explain both.
- An observational comparison (e.g. comparing two existing groups) is weaker evidence for causation than a controlled experiment, since self-selection or other factors could explain a difference.
What your child will practise:
- Identifying the data type(s) (categorical/numerical) needed to investigate a given question.
- Using a sample statistic to estimate a population value, as part of reporting findings.
- Calculating percentage change to quantify an investigation's result.
- Comparing the strength of evidence from two investigations based on sample size and method.
- Identifying a plausible confounding variable that challenges a causal conclusion.
Every section opens with a worked example, and the download includes a full answer key with step-by-step solutions and teaching notes on the mistakes students most commonly make.
.webp)
.webp)
%20(1).webp)
