conceptual regression analysis

If the correlation between X and Y is zero, what is the best predictor of the value of Y?

The mean of Y.

In a linear regression analysis, what happens to the residuals as Pearson's r increases?

The values of the residuals decrease.

Can a nominal predictor be used in linear regression analysis alongside an interval-ratio level predictor?

Yes, a nominal predictor can be used.

In linear regression, if the slope is +.50, what does it indicate?

For every unit increase in X, Y increases by 0.5 units.

In linear regression, if the slope is -.25, what occurs with each unit increase in X?

Every unit increase in X will result in a 1/4 unit decrease in Y.

What is the term for the change in value of Y that occurs with each unit change in X in linear regression?

Slope

What is the value of X when Y is 0 known as?

Intercept.

What factors determine the intercept in linear regression analysis?

The mean of Y, the mean of X, and the slope of the regression line.

What does the regression line represent?

The line that minimizes the residuals when using the value of X to predict the value of Y.

What is determined by the sign and absolute value of Pearson's r for X and Y in linear regression?

The slope of the regression line.

When all points in a scatterplot lie on the regression line, what is the correlation between the two variables?

+1.0 or -1.0.

In the case of two predictors where the multiple R is NOT significant, what should you do?

Perform simple linear regression with the strongest predictor.

The larger the multiple R, what can be said about the predicted values of Y?

The predicted values will be farther from the mean of Y.

As the correlation between the two predictor variables increases, what happens to the value of multiple R?

It will decrease.