Page 72 - IM_Algebra1_FL Print Sample.pdf

Unit Narrative
In grade 8, students informally constructed scatter plots and lines of t, noticed linear patterns, and observed associations in categorical data using two-way tables. In this unit, students build on this previous knowledge by assessing how well a linear model matches the data using residuals as well as the correlation coe cient for best- t lines (found using technology). The unit also revisits two-way tables to nd associations in categorical data using relative frequencies.
The unit begins with categorical data arranged into two-way tables that students manipulate to examine the relative frequencies of combinations of categories. Students nd the relative frequencies for combinations relative to the whole data set as well as row or column relative frequencies to look at subgroups within categories. The row and column relative frequency tables are ultimately used to nd evidence whether any associations are present in the data.
The unit then transitions to bivariate numerical data which are visualized using scatter plots and lines of best t. Students use technology to compute the lines of best t and observe how well the linear models match the data. Residuals and correlation coe cients are used to quantify the goodness of t for linear models.
The unit closes with an exploration of the di erence between correlation and causal relationships as well as an opportunity to apply their learning to anthropology and sports.
Required Materials
Copies of blackline master
Pre-printed slips, cut from copies of the blackline master
Rulers
Tools for creating a visual display
Any way for students to create work that can be easily displayed to the class. Examples: chart
paper and markers, whiteboard space and markers, shared online drawing tool, access to a document camera.
Unit 3 Table of Contents
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