SR Unit 3 Final Review

Front

What is the correlation between the number of times a student skips class and their exam score?

Back

Negative correlation: As the number of times a student skips class increases, their exam score tends to decrease.

Front

True or False: r tells the strength of a linear relationship.

Back

True: The correlation coefficient (r) indicates how strong the linear relationship is between two variables.

Front

True or False: r can only be calculated for graphs with 2 numerical (quantitative) variables.

Back

True: The correlation coefficient is applicable only for pairs of numerical variables.

Front

Estimate the correlation coefficient for a scatterplot that shows a strong negative trend.

Back

r = -0.9: This indicates a strong negative correlation.

Front

True or False: r is always between 0 and 1.

Back

False: The correlation coefficient (r) can range from -1 to 1.

Front

What does a correlation coefficient of 1 indicate?

Back

A perfect positive correlation: As one variable increases, the other variable also increases perfectly.

Front

What does a correlation coefficient of -1 indicate?

Back

A perfect negative correlation: As one variable increases, the other variable decreases perfectly.

Front

What does a correlation coefficient of 0 indicate?

Back

No correlation: There is no linear relationship between the two variables.

Front

What is the formula for calculating the correlation coefficient (r)?

Back

r = (nΣxy - ΣxΣy) / sqrt[(nΣx^2 - (Σx)^2)(nΣy^2 - (Σy)^2)]

Front

What is the significance of a correlation coefficient close to 0?

Back

It suggests a weak linear relationship between the variables.