More with Conditional, Joint, and Marginal Frequencies
Lesson 12 of 19
Objective: SWBAT compute conditional, joint and marginal frequencies given a two-way table. SWBAT design and build a two-way table based on a statistical question.
Students work with their partners on the Music Survey activity and conduct an analysis of the information given in the two-way table. I give students about 10 minutes to write down everything they can for each question. It is important to constantly push students to support their writing with evidence from the data. As they answer each question they should be supporting their answers with, “…because [the data says…].” I have found that if I continue to push students to write well-supported ideas, they will be more likely to think this way on their own.
As we prepare for the end of class, I ask all of the students to draw a new, blank Two-Way Table. I say, "I want you to make one just like the one you constructed for your survey question." I give the students a few minutes to create a neat table. Then I say, "Now, I want you to imagine that you were able to ask 200 students the same question. Use your percentages (joint and marginal relative frequencies) to fill in the number of people out of 200 for each cell in your new table." I will collect these new tables from each group before they leave the room.
Extension: If today's activity went well and I think it will be productive, I will ask my students to post their question on social media and try to collect as much data as possible. I am pretty confident that my students will be excited to compare this larger data set to their results from the classroom survey. If I pose this challenge, I will frame the project with the following question:
- Were the results similar or different to what you found in class?
- What do you think accounted for these similarities and differences?