Statistical Investigations: Level 2

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The key idea of statistical investigations at level 2 is letting go of the individual’s story and moving towards telling the class story.

At level 2 students are building on the ideas from level one and refining their understanding of different aspects of the PPDAC (Problem, Plan, Data, Analysis, Conclusion) cycle.  A key transition point at this level is moving students’ data display knowledge from individual case plots to frequency plots of the variable of interest.

Investigative questions will be similar to those posed previously and will include categorical and whole number variables.

Data displays become a summary of the individual case plots that they were drawing at the previous level.  For example, the number of children in a family is now on the horizontal axis.  Students place themselves on the graph according to the number of children in their family (this could be through using sticky notes).  As each student adds their sticky note to the display the frequency builds up. The frequency is recorded on the vertical axis.

Students will be making summary statements, for example, three students in our class have four children in their family (read the data), or five students have 1 or 2 children in their family (read between the data).

Teachers should be encouraging students to read beyond the data by asking questions such as: “If a new student joined our class, how many children do you think would be in their family?”

This key idea develops from the key idea of statistical investigations at level 1 where students are collecting data as evidence to tell a story about a question of interest.

This key idea is extended in the key idea of statistical investigations at level 3 where students are telling the class story with supporting evidence.