Unit 3: Two-Variable Statistics

Students use statistical methods to look for associations in bivariate data, working with two-way tables, scatter plots, lines of best fit, residuals, and correlation coefficients.

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What this unit covers

A Two-Way Tables · 3 lessons

Goals

• Create relative frequency tables from information given in a two-way table or about a situation.
• Inspect patterns in relative frequency tables and two-way tables to determine if there is a possible association between two variables of interest.

Lessons

1. Two-Way Tables
2. Relative Frequency Tables
3. Associations in Categorical Data

B Scatter Plots · 3 lessons

Goals

• Comprehend the connection between residuals, variability, and whether or not using a linear model is appropriate.
• Interpret the rate of change and vertical intercept for a linear model in the context of a situation.

Lessons

1. Linear Models
2. Fitting Lines
3. Residuals

C Correlation Coefficients · 3 lessons

Goals

• Describe the strength and sign of the relationship between variables based on the correlation coefficient.
• Investigate the relationship between two variables to analyze whether or not the relationship is causal.

Lessons

1. The Correlation Coefficient
2. Using the Correlation Coefficient
3. Causal Relationships

D Let's Put It to Work · 1 lesson

Lessons

1. Fossils and Flags (Optional)