AP Stats Ch.3 Review

Front

What is correlation in statistics?

Back

Correlation is a statistical measure that describes the strength and direction of a relationship between two variables.

Front

What does a correlation coefficient (r) of -0.71 indicate?

Back

A correlation coefficient of -0.71 indicates a strong negative relationship between the two variables, meaning as one variable increases, the other tends to decrease.

Front

What does a correlation coefficient (r) of 0.86 suggest about two variables?

Back

A correlation coefficient of 0.86 suggests a strong positive relationship, indicating that as one variable increases, the other variable also tends to increase.

Front

What is the difference between an explanatory variable and a response variable?

Back

The explanatory variable is the variable that is manipulated or changed to observe its effect on the response variable, which is the outcome being measured.

Front

What is the least squares regression line (LSRL)?

Back

The least squares regression line (LSRL) is a straight line that best fits the data points in a scatterplot, minimizing the sum of the squares of the vertical distances of the points from the line.

Front

What does it mean if a scatterplot shows a linear relationship?

Back

A linear relationship in a scatterplot indicates that the data points tend to follow a straight line pattern, suggesting a consistent relationship between the two variables.

Front

What is the coefficient of determination (R²)?

Back

The coefficient of determination (R²) measures the proportion of variance in the response variable that can be explained by the explanatory variable in a regression model.

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What is a strong negative relationship?

Back

A strong negative relationship occurs when an increase in one variable is associated with a significant decrease in another variable, often represented by a correlation coefficient close to -1.

Front

What is an example of a situation that might show a strong positive correlation?

Back

An example of a strong positive correlation is the relationship between the number of hours studied and exam scores, where more study time typically leads to higher scores.

Front

What happens to the correlation coefficient when the roles of the explanatory and response variables are switched?

Back

The correlation coefficient remains the same regardless of which variable is considered explanatory or response, as it measures the strength of the relationship between the two variables.