In: Statistics and Probability
sleep= β0+β1totwrk+β2educ+β3male+u.
and answer the following questions. Here the variable sleep is total minutes per week spent at night, totwrk is total weekly minutes spent working, educ and age are measured in years, and male is a gender dummy.
please give some good details
educ | male | sleep | totwrk |
12 | 1 | 3113 | 3438 |
14 | 1 | 2920 | 5020 |
17 | 1 | 2670 | 2815 |
12 | 0 | 3083 | 3786 |
14 | 1 | 3448 | 2580 |
12 | 1 | 4063 | 1205 |
12 | 1 | 3180 | 2113 |
13 | 1 | 2928 | 3608 |
17 | 1 | 3368 | 2353 |
15 | 1 | 3018 | 2851 |
8 | 1 | 1575 | 6415 |
16 | 0 | 3295 | 370 |
16 | 1 | 3798 | 2438 |
5 | 1 | 3008 | 2693 |
12 | 1 | 3248 | 2526 |
12 | 1 | 3683 | 2950 |
17 | 1 | 3201 | 3003 |
14 | 1 | 2580 | 4011 |
12 | 1 | 3420 | 2300 |
17 | 1 | 3090 | 1543 |
sleep | |
3113 | |
2920 | |
2670 | |
3083 | |
3448 | |
4063 | |
3180 | |
2928 | |
3368 | |
Y= | 3018 |
1575 | |
3295 | |
3798 | |
3008 | |
3248 | |
3683 | |
3201 | |
2580 | |
3420 | |
3090 |
totwrk | educ | male | ||
1 | 3438 | 12 | 1 | |
1 | 5020 | 14 | 1 | |
1 | 2815 | 17 | 1 | |
1 | 3786 | 12 | 0 | |
1 | 2580 | 14 | 1 | |
1 | 1205 | 12 | 1 | |
1 | 2113 | 12 | 1 | |
1 | 3608 | 13 | 1 | |
1 | 2353 | 17 | 1 | |
X= | 1 | 2851 | 15 | 1 |
1 | 6415 | 8 | 1 | |
1 | 370 | 16 | 0 | |
1 | 2438 | 16 | 1 | |
1 | 2693 | 5 | 1 | |
1 | 2526 | 12 | 1 | |
1 | 2950 | 12 | 1 | |
1 | 3003 | 17 | 1 | |
1 | 4011 | 14 | 1 | |
1 | 2300 | 12 | 1 | |
1 | 1543 | 17 | 1 |
1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
3438 | 5020 | 2815 | 3786 | 2580 | 1205 | 2113 | 3608 | 2353 | 2851 | 6415 | 370 | 2438 | 2693 | 2526 | 2950 | 3003 | 4011 | 2300 | 1543 | |
X'= | 12 | 14 | 17 | 12 | 14 | 12 | 12 | 13 | 17 | 15 | 8 | 16 | 16 | 5 | 12 | 12 | 17 | 14 | 12 | 17 |
1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
20 | 58018 | 267 | 18 | |
X'X= | 58018 | 200879306 | 746890 | 53862 |
267 | 746890 | 3747 | 239 | |
18 | 53862 | 239 | 18 | |
2.2023116 | -0.00015131 | -0.099135 | -0.43324787 | |
-0.000151 | 3.67451E-08 | 5.35E-06 | -2.9731E-05 | |
(X'X)-1= | -0.099135 | 5.35396E-06 | 0.006286 | -0.00035514 |
-0.433248 | -2.9731E-05 | -0.000355 | 0.582482709 | |
62689 | ||||
X'Y= | 172500717 | |||
844807 | ||||
56311 | ||||
3813.0166 | ||||
B^=(X'X)-1X'Y= | -0.2981 | |||
-0.3231 | ||||
211.7362 |
The regression equation is
sleep= 3813.0166 - 0.2981*totwrk- 0.3231*educ+211.7362*male
1. In the estimation, β0=3813.0166 , β1=- 0.2981, β2=- 0.3231, β3=211.7362.
2. All other factors being equal, is there evidence that men sleep more than women?
Ans: The value of slope corresponding to the Male factor is 211.7362 with a positive sign. Whereas the p-value for the test is 0.465 and greater than 0.05 level of significance. Hence, under all other factors being equal, there is no evidence that men sleep more than women at the 0.05 level of significance.
3. (3 points) Based on the corresponding estimate, explain in words the estimated trade-off between working and sleeping.
Ans: The value of the slope corresponding to total weekly minutes spent working is - 0.2981 with p-value 0.001 So, when a minute increased on the spent working decreases the mean sleep by 0.2981 minutes per week spent at night.