Author Question: Second-order polynomial models: A) always curve upward. B) always curve downward. C) can curve ... (Read 134 times)

cherise1989 · **on:** Jun 24, 2018

Second-order polynomial models:

A) always curve upward.
B) always curve downward.
C) can curve upward or downward depending on the data.
D) measure interaction between variables.

Question 2

Which of the following statements is true?

A) If the confidence interval estimate for the regression slope coefficient crosses over zero, the average change in y for a one-unit change in x may be zero.
B) If the regression slope coefficient is very close to zero, this means that the relationship between the x and y variables is statistically insignificant.
C) A statistically significant regression slope coefficient indicates that for a one-unit change in y there will be a positive change in x by an amount equal to the regression slope coefficient.
D) It is acceptable to make predictions for y using x values that are outside the range of the data that was used in the regression.