In: Math
The SAT has gone through many revisions over the years. People argue that female students generally do worse on math tests but better on writing tests. Consider the following portion of data on 20 students who took the SAT test last year. Information includes each student’s score on the writing and math sections of the exam, the student’s GPA, and a Female dummy variable that equals 1 if the student is female, 0 otherwise.
Writing | Math | GPA | Gender |
620 | 600 | 3.44 | 0 |
570 | 550 | 3.04 | 0 |
540 | 540 | 2.67 | 0 |
580 | 610 | 3.29 | 0 |
590 | 590 | 3.36 | 0 |
550 | 520 | 2.88 | 1 |
580 | 610 | 3.20 | 0 |
480 | 510 | 2.30 | 0 |
590 | 570 | 3.17 | 1 |
620 | 660 | 3.71 | 0 |
530 | 520 | 2.38 | 0 |
610 | 600 | 3.25 | 1 |
600 | 530 | 3.13 | 1 |
640 | 580 | 3.51 | 1 |
540 | 570 | 2.82 | 1 |
540 | 500 | 2.38 | 0 |
560 | 620 | 3.39 | 0 |
550 | 540 | 2.73 | 0 |
540 | 590 | 3.03 | 0 |
540 | 520 | 2.84 | 0 |
a-1. Estimate a linear regression model with math score as the response variable and GPA and the female dummy variable as the explanatory variables. (Negative values should be indicated by a minus sign. Round your answers to 2 decimal places.)
MathˆMath^ = _______ + _______ GPA + _____Female.
a-2. Compute the predicted math score for a male and female student with a GPA of 3.5. (Round coefficient estimates to at least 4 decimal places and final answer to 2 decimal places.)
MathˆMath^ | |
Male student | |
Female student | |
using excel data analysis tool for regression,steps are: write
data>menu>data>data analysis>regression>enter
required labels>ok> and following o/p is obtained
SUMMARY OUTPUT | ||||||||
Regression Statistics | ||||||||
Multiple R | 0.886468 | |||||||
R Square | 0.785825 | |||||||
Adjusted R Square | 0.760628 | |||||||
Standard Error | 21.31292 | |||||||
Observations | 20 | |||||||
ANOVA | ||||||||
df | SS | MS | F | Significance F | ||||
Regression | 2 | 28332.91 | 14166.46 | 31.18714 | 2.05E-06 | |||
Residual | 17 | 7722.086 | 454.2403 | |||||
Total | 19 | 36055 | ||||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
Intercept | 274.1203 | 37.84651 | 7.242949 | 1.37E-06 | 194.2712 | 353.9695 | 194.2712 | 353.9695 |
GPA | 98.71444 | 12.54348 | 7.869781 | 4.56E-07 | 72.25001 | 125.1789 | 72.25001 | 125.1789 |
Gender | -21.1008 | 10.55492 | -1.99915 | 0.061839 | -43.3698 | 1.168104 | -43.3698 | 1.168104 |
a-1)
MathˆMath^ = 274.12 + 98.71 GPA - 21.10 Female.
a-2)
for female,
MathˆMath^ = 274.12 + 98.71 *3.5 - 21.10 *1 = 598.52
-----
for male
.MathˆMath^ = 274.12 + 98.71 *3.5 - 21.10 *0 = 619.62