Video 1: Two-Way Tables (Lessons 1–3)
Video 2: Scatter Plots (Lessons 4–6)
Video 3: Correlation Coefficients (Lessons 7–9)
In this unit, students learn about two-way tables and use them to determine if two categories have an association. For example, would you predict that a forecast of rain over a school is associated with the number of students wearing rain boots? What association do you think the rain has with students’ eye colors? It is possible for two things to have no association as you may have guessed for rain and students’ eye colors. With your student, make predictions about associations found in daily life. For example, do these pairs share an association? Length of time a plant spends in sunlight and its growth The size of a car and the amount of gas it takes to be full Number of open apps on your mobile phone and battery percentage What other associations can you think of together? Students can use tables and collected data to determine if two things are associated. One type of table is a two-way table, which organizes two categorical variables. A categorical variable is a variable that takes on values which can be divided into groups or categories. For example, color is a categorical variable which can take on values like red, blue, or green. In the table, you may notice that it has a total of four categories, but only two categorical variables (hand dominance and fruit preference). With your student, examine the data collected from 1,914 other students.
Prefer Mangoes | Prefer Pineapples | Total | |
Left-Handed | 50 | 66 | |
Right-Handed | 826 | 972 | |
Total | 1,914 |
Prefer Mangoes | Prefer Pineapples | Total | |
Left-Handed | 50 | 66 | 116 |
Right-Handed | 826 | 972 | 1,798 |
Total | 876 | 1,038 | 1,914 |
IM Algebra 1 is copyright 2019 Illustrative Mathematics and licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).