Question #129
Reading: Reading 1 Multiple Regression
PDF File: Reading 1 Multiple Regression.pdf
Page: 62
Status: Unattempted
Correct Answer: A
Question
Which of the following statements regarding the R2 is least accurate?
Answer Choices:
A. R2 is the coefficient of determination of the regression
B. The R2 of a regression will be greater than or equal to the adjusted-R2 for the same regression. C) The R2 is the ratio of the unexplained variation to the explained variation of the dependent variable.
Explanation
The R2 is the ratio of the explained variation to the total variation.
(Module 1.2, LOS 1.d)
Manuel Mercado, CFA has performed the following two regressions on sales data for a given
industry. He wants to forecast sales for each quarter of the upcoming year.
Model ONE
Regression Statistics
Multiple R
0.941828
R2
0.887039
Adjusted R2
0.863258
Standard Error
2.543272
Observations
24
Durbin-Watson test statistic = 0.7856
ANOVA
df
SS
MS
F
Significance F
Regression
4
965.0619
241.2655
37.30006
9.49E−09
Residual
19
122.8964
6.4682
Total
23
1087.9583
Coefficients
Standard Error
t-Statistic
Intercept
31.40833
1.4866
21.12763
Q1
−3.77798
1.485952
−2.54246
Q2
−2.46310
1.476204
−1.66853
Q3
−0.14821
1.470324
−0.10080
TREND
0.851786
0.075335
11.20848
Model TWO
Regression Statistics
Multiple R
0.941796
R2
0.886979
Adjusted R2
0.870026
Standard Error
2.479538
Observations
24
Durbin-Watson test statistic = 0.7860
df
SS
MS
F
Significance F
Regression
3
964.9962
321.6654
52.3194
1.19E−09
Residual
20
122.9622
6.14811
Total
23
1087.9584
Coefficients
Standard Error
t-Statistic
Intercept
31.32888
1.228865
25.49416
Q1
−3.70288
1.253493
−2.95405
Q2
−2.38839
1.244727
−1.91881
TREND
0.85218
0.073991
11.51732
The dependent variable is the level of sales for each quarter, in $ millions, which began with
the first quarter of the first year. Q1, Q2, and Q3 are seasonal dummy variables representing
each quarter of the year. For the first four observations the dummy variables are as follows:
Q1:(1,0,0,0), Q2:(0,1,0,0), Q3:(0,0,1,0). The TREND is a series that begins with one and
increases by one each period to end with 24. For all tests, Mercado will use a 5% level of
significance. Tests of coefficients will be two-tailed, and all others are one-tailed.