Statistical Investigations: Level 7

The key idea of statistical investigations at level 7 is creating and telling a story about a wider universe, considering sampling variability and sample size effects, with supporting evidence.

Students are using the PPDAC (Problem, Plan, Data, Analysis, Conclusion) cycle in different data collection contexts.  A key focus at this level is the use of surveys and associated random sampling techniques.  Key transitions at this level include the integration of statistical and relevant contextual knowledge to answer investigative questions and making informal estimated comparison intervals for population parameters from samples. 

At this level students will be aware of how to design a suitable questionnaire specific to a given purpose and they will be using random sampling techniques in the data collection phase.  They should be evaluating choice of measures for variables and sampling and data collection methods.  Students should be provided with relevant contextual knowledge about the situation under investigation. 

Students will confidently be using informal estimated comparison intervals to make comparisons about populations from sample distributions.

This key idea develops from the key idea of statistical investigations at level 6 where students were  telling a story about a wider universe taking variation and uncertainty into account.

This key idea is extended in the key idea of statistical investigations at level 8 where students are supporting their story with sophisticated statistical techniques and informed contextual knowledge.