Statistical investigation
Choose a subtopic, explore its examples and practise with feedback.
Choose a subtopic.
Explore statistical investigation for Year 11. Each subtopic has sample questions and worked answers; choose the skill you want to practise.
The statistical investigation process
Question/problem, investigation method, data collection, analysis, interpretation and assumptions; Critiquing statistical claims and evidence
Examples, answers and practiceSampling and collecting data
Purpose of sampling and target population; Bias and reliability; Simple random, stratified and systematic samples; Sample size effects
Examples, answers and practiceClassifying and organising data
Nominal/ordinal and discrete/continuous data; Frequency/count/proportion tables; Bar/pie charts, dot/stem plots and histograms; Appropriate and misleading displays; justified treatment of outliers
Examples, answers and practiceThe shape, location, and spread of distributions of numerical data
Distribution shape: symmetry, skew and modes; Mean/median choice and outliers; Box plots, quartiles, range/IQR, standard deviation; 1.5-IQR outlier fences; Sample statistics versus population parameters and sample-size reliability
Examples, answers and practiceForming and supporting conjectures across two or more groups
Comparison across groups using suitable common-scale displays; Handling outliers, shape, centre and spread; Categorical proportions and modal category; Evidence-based conjectures and limitations
Examples, answers and practice