Te reo Māori terms
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Learning objective overview
Master Teaching Guide coverage for this objective.
S6-1
NZC26-P4-STA-INT-K-Y10-01NZC26-P4-STA-DKD-K-Y10-03NZC26-P4-STA-INT-P-Y10-02NZC26-P4-STA-INT-K-Y10-02NZC26-P4-STA-INT-K-Y10-03NZC26-P4-STA-INT-K-Y9-02
Resources
- CensusAtSchool NZ - Sampling variation: developing big ideas for sample-to-population inferencesQuestions PDF · Answers
- CorbettMaths - Box PlotsQuestions PDF · Answers
Terminology
- Sample
- Population
- Median
- Quartile
- Interquartile range
- Overlap
- Inference
- Box plot
Task goals
- Foundation: Compare two sample box plots and state which group has the higher median, using correct statistical language.
- Proficient: Write a full inference statement about the population by comparing sample medians and checking whether the middle 50% (IQR) overlap, justifying a claim about a true population difference.
- Excellence: Critique the strength of an inference by discussing sample size, degree of overlap, and the limits of generalising sample conclusions to the wider population.
Where this fits
What leads into this objective, and where it goes next.
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Making an Inference from Sample Data
To compare data on the same variable from two groups in the same population, the 75%-to-50% comparison rule for informal inferences is used. If the groups are called A and B, and if more than 50% of group B's data is larger than 75% of group A's data, then we can make the claim that B tends to be larger than A back in the population.
Statement▸
When sampling from a population, the distribution for a variable varies from sample to sample. To make a reliable inference about what is happening in the population, sample sizes need to be: about 1,000 for categorical variables (with the sample obtained using technology); at least 30 for numerical variables.
Statement▸
Also under S6-1:
For teachers
Need the fuller teaching notes for this objective? Open the Teacher guidance PDF.