Two Variable Data: Models and Scatterplots
Scatterplots, lines of best fit, and choosing the right model type
You get a scatterplot or a line of best fit. The question asks: what does the data tell you?
Why this matters
Two-variable data questions test whether you can read graphs, use models, and interpret what slope and intercept mean in context. Students rush through these and misread what's being asked. There are four question types — from reading data points to choosing the best model — and each requires a different approach.
The four patterns
Interpret Data Relationships
Read a scatterplot to identify trends, associations, or specific data points. Is it positive, negative, or no association?
›Estimation and Prediction
Use a line of best fit to estimate a value or predict what happens at a given input. Stay close to the line, not the individual points.
›Meaning of Model Components
Explain what the slope or y-intercept means in real-world terms. Slope = rate of change per unit. Intercept = starting value.
›Model Evaluation
Decide whether a linear, quadratic, or exponential equation best fits the data. Look at the shape — straight line, curve, or rapid growth.