Interpreting Scatter Plots: Association
This Grade 11 math skill from enVision Algebra 1 teaches students to interpret association in scatter plots. A positive association means that as x-values increase, y-values also tend to increase — showing an upward trend. A negative association means that as x-values increase, y-values tend to decrease — a downward trend. No association means there is no clear pattern between the variables. Identifying the type and direction of association in a scatter plot is a foundational skill for statistical reasoning and regression analysis in Algebra 1.
Key Concepts
Positive Association : As $x$ values increase, $y$ values tend to increase (upward trend).
Negative Association : As $x$ values increase, $y$ values tend to decrease (downward trend).
Common Questions
What is a positive association in a scatter plot?
A positive association means that as x-values increase, y-values also tend to increase. The data points form an upward trend from left to right on the scatter plot.
What is a negative association in a scatter plot?
A negative association means that as x-values increase, y-values tend to decrease. The data points form a downward trend from left to right on the scatter plot.
What does no association mean in a scatter plot?
No association means there is no clear pattern or relationship between x and y values. The data points appear randomly scattered without any upward or downward trend.
How do you determine the type of association from a scatter plot?
Look at the overall direction of the data cloud: if points trend up from left to right, it is positive; if they trend down, it is negative; if points are scattered randomly with no direction, there is no association.
Why is identifying association important in data analysis?
Identifying association helps determine whether two variables are related and in which direction. This guides decisions about which regression model to apply and whether one variable can be used to predict the other.