Question

In: Statistics and Probability

(2pt) A variable that takes on the values of 0 or 1 and is used to...

(2pt) A variable that takes on the values of 0 or 1 and is used to incorporate the effect of categorical variables in a regression model is called

a.	a constant variable
b.	a dummy variable
c.	an interaction
d.	None of these alternatives are correct.

(1pt) The model y= β0+β1x1+β2x12+ε is called

a.	First-order model with one predictor variable
b.	Second-order model with two predictor variables
c.	Second-order model with one predictor variable
d.	None of these alternatives is correct

(2pt) Which of the following tests is used to determine whether an additional set of variables (more than one independent variables) makes a significant contribution to a multiple regression?

a.	T test
b.	Z test
c.	Chi-square test
d.	F test

(1pt) When dealing with the problem of non-constant variance, the log transformation means using

a.	1/X as the independent variable instead of X
b.	LogX as the independent variable instead of X
c.	LogY as the dependent variable instead of Y
d.	1Y as the dependent variable instead of Y

(1pt) A variable such as Z, whose value is Z = X₁X₂ is added to a general linear model in order to account for potential effects of two variables X₁ and X₂ acting together. This type of effect is

a.	called interaction
b.	called transformation effect
c.	called multicollinearity effect
d.	impossible to occur

(1pt) In multiple regression analysis, the word linear in the term "general linear model" refers to the fact that

a.	b₀, b₁, . . . b_p, all have exponents of less than 1
b.	b₀, b₁, . . . b_p, all have exponents of more than 1
c.	b₀, b₁, . . . b_p, all have exponents of 1
d.	b₀, b₁, . . . b_p, all have exponents of 0

7. (1pt) A term used to describe the case when the independent variables in a multiple regression model are correlated is

a. regression

b. correlation

c. multicollinearity

d. None of the above answers is correct

8. (1pt) All the independent variables in a multiple regression analysis

a. must be quantitative

b. must be either quantitative or categorical but not a mix of both

c. must assume only positive values

d. can be either quantitative or categorical

Expert Solution

orchestra answered 2 years ago

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