In: Math
Many regions along the coast in North and South Carolina and Georgia have experienced rapid population growth over the last 10 years. It is expected that the growth will continue over the next 10 years.
|
Family | Food | Income | Size | ||||
1 | $3.84 | $73.98 | 1 | ||||
2 | 4.08 | 54.90 | 2 | ||||
3 | 5.76 | 53.20 | 4 | ||||
4 | 3.48 | 52.02 | 1 | ||||
5 | 4.20 | 65.70 | 2 | ||||
6 | 4.80 | 53.64 | 4 | ||||
7 | 4.32 | 79.74 | 3 | ||||
8 | 5.04 | 68.58 | 4 | ||||
9 | 6.12 | 165.60 | 5 | ||||
10 | 3.24 | 64.80 | 1 | ||||
11 | 4.80 | 138.42 | 3 | ||||
12 | 3.24 | 125.82 | 1 | ||||
13 | 7.20 | 77.58 | 7 | ||||
14 | 6.40 | 94.15 | 5 | ||||
15 | 6.60 | 135.76 | 8 | ||||
16 | 5.40 | 141.30 | 3 | ||||
17 | 6.00 | 36.90 | 5 | ||||
18 | 5.40 | 56.88 | 4 | ||||
19 | 3.36 | 71.82 | 1 | ||||
20 | 4.68 | 69.48 | 3 | ||||
21 | 4.32 | 54.36 | 2 | ||||
22 | 5.52 | 87.66 | 5 | ||||
23 | 4.56 | 38.16 | 3 | ||||
24 | 5.40 | 43.74 | 7 | ||||
25 | 5.90 | 62.40 | 6 | ||||
(a-1) |
Develop a correlation matrix. (Round your answers to 3 decimal places. Negative amounts should be indicated by a minus sign.) |
Food | Income | |
Income | ||
Size | ||
(b-1) | Determine the regression equation. (Round your answers to 3 decimal places. Leave no cells blank - be certain to enter "0" wherever required.) |
The regression equation is: Food = + Income + Size. |
(b-2) |
How much does an additional family member add to the amount spent on food? (Round your answer to the nearest dollar amount.) |
Another member of the family adds $ to the food bill. |
(c-1) | What is the value of R2? (Round your answer to 3 decimal places.) |
(c-2) |
State the decision rule for 0.05 significance level. H0: β1 = β2 = 0; H1: Not all βi's are 0. (Round your answer to 2 decimal places.) |
Source | DF | SS | MS | F | p |
Regression | |||||
Error | |||||
Total | |||||
(c-3) | Complete the ANOVA (Leave no cells blank - be certain to enter "0" wherever required. Round SS, MS to 3 decimal places and F to 2 decimal places.) |
(d-1) |
Complete the given below table. (Leave no cells blank - be certain to enter "0" wherever required. Do not round the intermediate calculations. Round T to 2 decimal places and all other values to 3 decimal places.) |
Predictor | Coef | SE Coef | T | P |
Income | ||||
Size | ||||
Correlation matrix is :
Food | Income | |
Income | 0.214 | 1 |
Size | 0.911 | 0.127 |
(Using excal to find correlation we have command =correl(array1(select income column), array2 (select food column)))
Excel Output is :
SUMMARY OUTPUT | ||||||||
Regression Statistics | ||||||||
Multiple R | 0.916257008 | |||||||
R Square | 0.839526904 | |||||||
Adjusted R Square | 0.824938441 | |||||||
Standard Error | 0.460007547 | |||||||
Observations | 25 | |||||||
ANOVA | ||||||||
df | SS | MS | F | Significance F | ||||
Regression | 2 | 24.35482325 | 12.17741162 | 57.54731596 | 1.81729E-09 | |||
Residual | 22 | 4.655352752 | 0.211606943 | |||||
Total | 24 | 29.010176 | ||||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
Intercept | 2.961284867 | 0.267969205 | 11.05084022 | 1.90198E-10 | 2.40555075 | 3.51701898 | 2.40555075 | 3.517018984 |
Income | 0.003093656 | 0.002679566 | 1.154536202 | 0.260667834 | -0.002463424 | 0.00865074 | -0.00246342 | 0.008650735 |
Size | 0.483821397 | 0.046378329 | 10.43205762 | 5.56074E-10 | 0.38763863 | 0.58000416 | 0.38763863 | 0.580004164 |
Using Excel Output :
Part b-1. The regression equation is
Food = income + size
The general regression equation is ,
Y(food) = b0+b1*income + b2*size
Y (food) = 2.961+0.003*income+0.484*size (rounded to 3 decimal )
Part b-2.
If family member is 1 (size = 1) then food cost will be $3.445
y = 2.961 + 0.484*1 = 2.961+0.484 = 3.445
If family member is 2 then food cost will be $3.929
y = 2.961+0.484*2 = 3.929
Ans : Means another family member adds $0.484 to the food bill . If no family member is add then food bill is $2.961.
Part . C-1 .
R2 = 0.839
Part C-2 .
Using F test we have F = 57.55
and P value = 0.00 and alpha = 0.05
P value (0.0000) < alpha (0.05) we reject H0 and conclude that Bi's is significant . (or we can say that model is significant).
Part C-3.
Rounded value into 2 decimal place.
ANOVA | |||||
df | SS | MS | F | P | |
Regression | 2 | 24.355 | 12.177 | 57.55 | 0.000 |
Error | 22 | 4.655 | 0.212 | ||
Total | 24 | 29.010 |
Part d-1.
Predictor | Coef | SE Coef | T | P |
Income | 0.003 | 0.003 | 1.15 | 0.261 |
Size | 0.484 | 0.046 | 10.43 | 0.000 |
To get excel output . Enter data then select DATA ---> Data Analysis ----> Regression
y = select food column
x = select size and income column
Okay.