In: Statistics and Probability
For the dataset describing year, US Return, and Overseas Return
1. Find the least-squares regression equation of overseas returns on U.S. returns.
2. In 1997, the return on U.S. stocks was 33.4%. Use the regression line to predict the return on overseas stocks. (You may either calculate this by hand or use SAS output.) The actual overseas return was 2.1%. Are you confident that predictions using the regression line will be quite accurate? Why?
DATA
1971 29.6 14.6 1972 36.3 18.9 1973 -14.9 -14.8 1974 -23.2 -26.4 1975 35.4 37.2 1976 2.5 23.6 1977 18.1 -7.4 1978 32.6 6.4 1979 4.8 18.2 1980 22.6 32.3 1981 -2.3 -5.0 1982 -1.9 21.5 1983 23.7 22.4 1984 7.4 6.1 1985 56.2 31.6 1986 69.4 18.6 1987 24.6 5.1 1988 28.5 16.8 1989 10.6 31.5 1990 -23.0 -3.1 1991 12.8 30.4 1992 -12.1 7.6 1993 32.9 10.1 1994 6.2 1.3 1995 11.2 37.6 1996 6.4 23.0 1997 2.1 33.4
Solution:
In SAS use key words DATA to create dataset
Input statement to describe variables
Procedure regression to fit linear regression of Overseas_Return on US_Return.
SAS Code;
data stock;
infile cards;
input year US_Return Overseas_Return;
cards;
1971 29.6 14.6
1972 36.3 18.9
1973 -14.9 -14.8
1974 -23.2 -26.4
1975 35.4 37.2
1976 2.5 23.6
1977 18.1 -7.4
1978 32.6 6.4
1979 4.8 18.2
1980 22.6 32.3
1981 -2.3 -5.0
1982 -1.9 21.5
1983 23.7 22.4
1984 7.4 6.1
1985 56.2 31.6
1986 69.4 18.6
1987 24.6 5.1
1988 28.5 16.8
1989 10.6 31.5
1990 -23.0 -3.1
1991 12.8 30.4
1992 -12.1 7.6
1993 32.9 10.1
1994 6.2 1.3
1995 11.2 37.6
1996 6.4 23.0
1997 2.1 33.4
;
run;
proc reg data=stock;
model Overseas_Return=US_Return/ r cli clm;;
run;
Output;
The REG Procedure
Model: MODEL1
Dependent Variable: Overseas_Return
Number of Observations Read | 27 |
---|---|
Number of Observations Used | 27 |
Analysis of Variance | |||||
---|---|---|---|---|---|
Source | DF | Sum of Squares |
Mean Square |
F Value | Pr > F |
Model | 1 | 1517.67778 | 1517.67778 | 6.86 | 0.0147 |
Error | 25 | 5527.78222 | 221.11129 | ||
Corrected Total | 26 | 7045.46000 |
Root MSE | 14.86981 | R-Square | 0.2154 |
---|---|---|---|
Dependent Mean | 14.50000 | Adj R-Sq | 0.1840 |
Coeff Var | 102.55042 |
Parameter Estimates | |||||
---|---|---|---|---|---|
Variable | DF | Parameter Estimate |
Standard Error |
t Value | Pr > |t| |
Intercept | 1 | 9.39847 | 3.46136 | 2.72 | 0.0118 |
US_Return | 1 | 0.34739 | 0.13260 | 2.62 | 0.0147 |
The REG Procedure
Model: MODEL1
Dependent Variable: Overseas_Return
Output Statistics | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Obs | Dependent Variable |
Predicted Value |
Std Error Mean Predict |
95% CL Mean | 95% CL Predict | Residual | Std Error Residual |
Student Residual |
Cook's D | ||
1 | 14.6 | 19.6813 | 3.4786 | 12.5170 | 26.8456 | -11.7705 | 51.1331 | -5.0813 | 14.457 | -0.351 | 0.004 |
2 | 18.9 | 22.0088 | 4.0502 | 13.6674 | 30.3503 | -9.7318 | 53.7495 | -3.1088 | 14.308 | -0.217 | 0.002 |
3 | -14.8 | 4.2223 | 4.8558 | -5.7784 | 14.2230 | -27.9942 | 36.4388 | -19.0223 | 14.055 | -1.353 | 0.109 |
4 | -26.4 | 1.3389 | 5.7814 | -10.5681 | 13.2460 | -31.5193 | 34.1972 | -27.7389 | 13.700 | -2.025 | 0.365 |
5 | 37.2 | 21.6962 | 3.9666 | 13.5268 | 29.8656 | -9.9996 | 53.3920 | 15.5038 | 14.331 | 1.082 | 0.045 |
6 | 23.6 | 10.2669 | 3.2863 | 3.4986 | 17.0353 | -21.0970 | 41.6309 | 13.3331 | 14.502 | 0.919 | 0.022 |
7 | -7.4 | 15.6863 | 2.8973 | 9.7192 | 21.6534 | -15.5146 | 46.8871 | -23.0863 | 14.585 | -1.583 | 0.049 |
8 | 6.4 | 20.7235 | 3.7192 | 13.0637 | 28.3832 | -10.8448 | 52.2918 | -14.3235 | 14.397 | -0.995 | 0.033 |
9 | 18.2 | 11.0660 | 3.1476 | 4.5833 | 17.5486 | -20.2376 | 42.3695 | 7.1340 | 14.533 | 0.491 | 0.006 |
10 | 32.3 | 17.2496 | 3.0481 | 10.9719 | 23.5272 | -14.0122 | 48.5113 | 15.0504 | 14.554 | 1.034 | 0.023 |
11 | -5.0 | 8.5995 | 3.6417 | 1.0993 | 16.0996 | -22.9305 | 40.1294 | -13.5995 | 14.417 | -0.943 | 0.028 |
12 | 21.5 | 8.7384 | 3.6091 | 1.3053 | 16.1715 | -22.7757 | 40.2525 | 12.7616 | 14.425 | 0.885 | 0.024 |
13 | 22.4 | 17.6317 | 3.1013 | 11.2444 | 24.0190 | -13.6523 | 48.9156 | 4.7683 | 14.543 | 0.328 | 0.002 |
14 | 6.1 | 11.9692 | 3.0203 | 5.7487 | 18.1897 | -19.2811 | 43.2195 | -5.8692 | 14.560 | -0.403 | 0.003 |
15 | 31.6 | 28.9220 | 6.2042 | 16.1442 | 41.6997 | -4.2617 | 62.1057 | 2.6780 | 13.514 | 0.198 | 0.004 |
16 | 18.6 | 33.5076 | 7.7991 | 17.4451 | 49.5700 | -1.0741 | 68.0892 | -14.9076 | 12.660 | -1.177 | 0.263 |
17 | 5.1 | 17.9443 | 3.1492 | 11.4584 | 24.4303 | -13.3599 | 49.2486 | -12.8443 | 14.533 | -0.884 | 0.018 |
18 | 16.8 | 19.2992 | 3.3978 | 12.3013 | 26.2970 | -12.1151 | 50.7135 | -2.4992 | 14.476 | -0.173 | 0.001 |
19 | 31.5 | 13.0808 | 2.9125 | 7.0824 | 19.0793 | -18.1260 | 44.2877 | 18.4192 | 14.582 | 1.263 | 0.032 |
20 | -3.1 | 1.4084 | 5.7584 | -10.4512 | 13.2681 | -31.4327 | 34.2495 | -4.5084 | 13.710 | -0.329 | 0.010 |
21 | 30.4 | 13.8451 | 2.8726 | 7.9289 | 19.7613 | -17.3461 | 45.0363 | 16.5549 | 14.590 | 1.135 | 0.025 |
22 | 7.6 | 5.1950 | 4.5611 | -4.1987 | 14.5888 | -26.8383 | 37.2283 | 2.4050 | 14.153 | 0.170 | 0.001 |
23 | 10.1 | 20.8277 | 3.7447 | 13.1154 | 28.5400 | -10.7534 | 52.4088 | -10.7277 | 14.391 | -0.745 | 0.019 |
24 | 1.3 | 11.5523 | 3.0749 | 5.2194 | 17.8852 | -19.7206 | 42.8252 | -10.2523 | 14.548 | -0.705 | 0.011 |
25 | 37.6 | 13.2893 | 2.8988 | 7.3191 | 19.2594 | -17.9122 | 44.4907 | 24.3107 | 14.585 | 1.667 | 0.055 |
26 | 23.0 | 11.6218 | 3.0653 | 5.3086 | 17.9349 | -19.6471 | 42.8907 | 11.3782 | 14.550 | 0.782 | 0.014 |
27 | 33.4 | 10.1280 | 3.3127 | 3.3053 | 16.9507 | -21.2477 | 41.5037 | 23.2720 | 14.496 | 1.605 | 0.067 |
Sum of Residuals | 0 |
---|---|
Sum of Squared Residuals | 5527.78222 |
Predicted Residual SS (PRESS) | 6548.38833 |
Solution-1;
he least-squares regression equation of overseas returns on U.S. returns
is
Overseas_Return=9.39847+0.34739*US_Return
Solution-2:
the regression line to predict the return on overseas stocks. (You may either calculate this by hand or use SAS output.) The actual overseas return was 2.1%. Are you confident that predictions using the regression line will be quite accurate
Obs | Dependent | Predicted | Std | 95% CL Mean | 95% CL Predict | Residual | Std Error | Student | Cook's D | ||
Variable | Value | Error | Residual | Residual | |||||||
Mean | |||||||||||
Predict | |||||||||||
27 | 33.4 | 10.128 | 3.3127 | 3.3053 | 16.9507 | -21.2477 | 41.5037 | 23.272 | 14.496 | 1.605 | 0.067 |
Predicted return on overseas stocks. is 10.128
we are confident that predictions are not accurate sicne R sq is less
R sq=0.2154
=21.54%
21.54% variation in Overseas_Return is explained by model
but From Global F test
p<0.05
Model is signifcant and we can use this model to predict Overseas_Return