Page 179 - IM_Algebra1_FL Print Sample.pdf

Give students 1 minute of quiet think time, and then 1 minute to discuss the things they notice with their partner, followed by a whole-class discussion.
Among things students should notice are:
1. the sign of is the same as the sign of the slope of the best t line
2. the values for seem to go from -1 to 1
3. the closer is to 1 or -1, the stronger the linear relationship between the variables 4. the closer is to 0, the weaker the linear relationship between the variables
Note that the sign of the correlation coe cient matches the sign of the slope of the best t line, but the value for is not otherwise related to the slope. If , the best t line will have a positive slope, but whether the slope is 0.2 or 2,000 is not clear without examining the data.
7.3 Matching Correlation Coe cients
10 minutes
In this activity students take turns with a partner working to understand the relationship between data shown in scatter plots and correlation coe cients. Students trade roles explaining their thinking and listening, providing opportunities to explain their reasoning and critique the reasoning of others (MP3).
Instructional Routines
• Take turns
What: Students work with a partner or small group. They take turns in the work of the activity, whether it be spotting matches, explaining, justifying, agreeing or disagreeing, or asking clarifying questions. If they disagree, they are expected to support their case and listen to their
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Teacher Guide Algebra