In: Statistics and Probability
An agent for a real estate company wanted to predict the monthly rent for apartments based on the size of the apartment. The data for a sample of 25 apartments is available below. Perform a t test for the slope to determine if a significant linear relationship between the size and the rent exists. a. At the 0.05 level of significance, is there evidence of a linear relationship between the size of the apartment and the monthly rent? b. Construct a 95% confidence interval estimate of the population slope, beta1.
Size_(sq._ft)   Rent_($)
850   1925
1460   2600
1075   2200
1222   2475
708   1925
1495   2675
1146   2650
726   1925
710   1875
966   2125
1100   2375
1285   2650
1995   3325
1369   2775
1185   2400
1235   2425
1255   2075
1249   2725
1140   2175
896   2125
1351   2600
1050   2650
765   2175
1010   1800
1200   2750
a. Determine hypothesis
b. t stat = ?
c. p value =
d. reach a decision to reject or not and with sufficient or insufficient evidence
e. Develop 95% confidence interval
| size | rent | 
| 850 | 1925 | 
| 1460 | 2600 | 
| 1075 | 2200 | 
| 1222 | 2475 | 
| 708 | 1925 | 
| 1495 | 2675 | 
| 1146 | 2650 | 
| 726 | 1925 | 
| 710 | 1875 | 
| 966 | 2125 | 
| 1100 | 2375 | 
| 1285 | 2650 | 
| 1995 | 3325 | 
| 1369 | 2775 | 
| 1185 | 2400 | 
| 1235 | 2425 | 
| 1255 | 2075 | 
| 1249 | 2725 | 
| 1140 | 2175 | 
| 896 | 2125 | 
| 1351 | 2600 | 
| 1050 | 2650 | 
| 765 | 2175 | 
| 1010 | 1800 | 
| 1200 | 2750 | 
EXCEL OUTPUT:
| SUMMARY OUTPUT | ||||||||
| Regression Statistics | ||||||||
| Multiple R | 0.849297387 | |||||||
| R Square | 0.721306052 | |||||||
| Adjusted R Square | 0.709188924 | |||||||
| Standard Error | 199.0735527 | |||||||
| Observations | 25 | |||||||
| ANOVA | ||||||||
| df | SS | MS | F | Significance F | ||||
| Regression | 1 | 2359103.574 | 2359103.574 | 59.5278058 | 7.93915E-08 | |||
| Residual | 23 | 911496.4256 | 39630.27938 | |||||
| Total | 24 | 3270600 | ||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
| Intercept | 1144.076975 | 164.5592794 | 6.952369861 | 4.36316E-07 | 803.6601689 | 1484.493781 | 803.6601689 | 1484.493781 | 
| SIZE | 1.082799832 | 0.140342188 | 7.715426482 | 7.93915E-08 | 0.792479897 | 1.373119767 | 0.792479897 | 1.373119767 | 
A) HO: β1=0
H1: β≠0 IS CORRECT.
B) t Stat value is 7.715426482
C) p-value is 0.0000000793915 ≈ 0
D) Here p-value is less than 0.05 so we reject the null hypothesis and also we have sufficient evidence that to conclude there is a relationship between monthly rent and apartment size.
E) The 95% C.I is 0.792479897480759 to 1.37311976723654