Ch 9 Regression Wisdom

Front

What does random scatter in the residuals indicate about a regression model?

Back

It indicates a model with high predictive power.

Front

What is the correlation coefficient range for two strongly associated variables?

Back

The correlation will be near +1.0 or -1.0.

Front

Does a high correlation between two variables imply causation?

Back

No, correlation does not imply causation.

Front

What does the regression equation Price^ = -19.4 + 0.1297(Area) represent?

Back

It represents the relationship between square footage (Area) and price of a house.

Front

What is the purpose of a line of best fit in regression analysis?

Back

To make predictions based on the data.

Front

What is a lurking variable?

Back

A variable that is not the explanatory or response variable but may influence the response variable.

Front

What is the difference between correlation and causation?

Back

Correlation indicates a relationship between two variables, while causation indicates that one variable directly affects the other.

Front

What does a negative correlation coefficient indicate?

Back

As one variable increases, the other variable tends to decrease.

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 p-value in regression analysis?

Back

A p-value indicates the probability that the observed results occurred by chance; a low p-value suggests statistical significance.