Chapter 9 Review

Front

What is the correlation coefficient and what does it indicate?

Back

The correlation coefficient (r) is a statistical measure that describes the strength and direction of a relationship between two variables. Values range from -1 to 1, where 1 indicates a perfect positive correlation, -1 indicates a perfect negative correlation, and 0 indicates no correlation.

Front

What does a y-intercept represent in a Least Squares Line Equation?

Back

The y-intercept represents the value of the dependent variable (y) when the independent variable (x) is zero. It indicates the starting point of the line on the y-axis.

Front

What does it mean if two variables are correlated?

Back

If two variables are correlated, it means they are related to each other in some way, but it does not imply that one variable causes the other.

Front

How do you calculate a line of best fit?

Back

A line of best fit is calculated using statistical methods such as least squares regression, which minimizes the sum of the squares of the vertical distances of the points from the line.

Front

What does a strong negative correlation indicate?

Back

A strong negative correlation indicates that as one variable increases, the other variable tends to decrease significantly.

Front

What is the formula for a linear equation in slope-intercept form?

Back

The formula for a linear equation in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.

Front

What is the significance of the slope in a linear equation?

Back

The slope (m) indicates the rate of change of the dependent variable (y) with respect to the independent variable (x). A positive slope means y increases as x increases, while a negative slope means y decreases as x increases.

Front

What does it mean if the correlation coefficient is 0?

Back

A correlation coefficient of 0 means there is no linear relationship between the two variables.

Front

What is the difference between strong and weak correlation?

Back

Strong correlation means the data points are closely clustered around a line, indicating a clear relationship, while weak correlation means the data points are more spread out, indicating a less clear relationship.

Front

What is the purpose of a scatterplot?

Back

A scatterplot is used to visually display the relationship between two quantitative variables, helping to identify patterns, trends, and correlations.