In: Statistics and Probability
As a real estate analyst, you are requested by the manager to construct a simple linear regression for the relationship between the house value (x) and the upkeep spending (y).
(a) Write the simple linear regression equation below.
(b) What are b0 and b1?
(c) Interpret the meanings of b0 and b1.
(d) If the house value (x) is 150, what will the upkeep spending (y) be, using the simple linear regression model 4a?
(e) Draw the scatterplot showing the relationship between the house value (x) and the upkeep spending (y).
Value X | Upkeep Y |
237.00 | 1412.08 |
153.08 | 797.20 |
184.86 | 872.48 |
222.06 | 1003.42 |
160.68 | 852.90 |
99.68 | 288.48 |
229.04 | 1288.46 |
101.78 | 423.08 |
257.86 | 1351.74 |
96.28 | 378.04 |
171.00 | 918.08 |
231.02 | 1627.24 |
228.32 | 1204.76 |
205.90 | 857.04 |
185.72 | 775.00 |
168.78 | 869.26 |
247.06 | 1396.00 |
155.54 | 711.50 |
224.20 | 1475.18 |
202.04 | 1413.32 |
153.04 | 849.14 |
232.18 | 1313.84 |
125.44 | 602.06 |
169.82 | 642.14 |
177.28 | 1038.80 |
162.82 | 697.00 |
120.44 | 324.34 |
191.10 | 965.10 |
158.78 | 920.14 |
178.50 | 950.90 |
272.20 | 1670.32 |
48.90 | 125.40 |
104.56 | 479.78 |
286.18 | 2010.64 |
83.72 | 368.36 |
86.20 | 425.60 |
133.58 | 626.90 |
212.86 | 1316.94 |
122.02 | 390.16 |
198.02 | 1090.84 |
a.
X - Mx | Y - My | (X - Mx)2 | (X - Mx)(Y - My) |
62.5115 | 493.9885 | 3907.6876 | 30879.9621 |
-21.4085 | -120.8915 | 458.3239 | 2588.1057 |
10.3715 | -45.6115 | 107.568 | -473.0597 |
47.5715 | 85.3285 | 2263.0476 | 4059.2047 |
-13.8085 | -65.1915 | 190.6747 | 900.1968 |
-74.8085 | -629.6115 | 5596.3117 | 47100.2919 |
54.5515 | 370.3685 | 2975.8662 | 20204.1572 |
-72.7085 | -495.0115 | 5286.526 | 35991.5436 |
83.3715 | 433.6485 | 6950.807 | 36153.9259 |
-78.2085 | -540.0515 | 6116.5695 | 42236.6177 |
-3.4885 | -0.0115 | 12.1696 | 0.0401 |
56.5315 | 709.1485 | 3195.8105 | 40089.2284 |
53.8315 | 286.6685 | 2897.8304 | 15431.7954 |
31.4115 | -61.0515 | 986.6823 | -1917.7192 |
11.2315 | -143.0915 | 126.1466 | -1607.1322 |
-5.7085 | -48.8315 | 32.587 | 278.7546 |
72.5715 | 477.9085 | 5266.6226 | 34682.5367 |
-18.9485 | -206.5915 | 359.0457 | 3914.599 |
49.7115 | 557.0885 | 2471.2332 | 27693.705 |
27.5515 | 495.2285 | 759.0852 | 13644.288 |
-21.4485 | -68.9515 | 460.0382 | 1478.9062 |
57.6915 | 395.7485 | 3328.3092 | 22831.3246 |
-49.0485 | -316.0315 | 2405.7554 | 15500.871 |
-4.6685 | -275.9515 | 21.7949 | 1288.2796 |
2.7915 | 120.7085 | 7.7925 | 336.9578 |
-11.6685 | -221.0915 | 136.1539 | 2579.8062 |
-54.0485 | -593.7515 | 2921.2404 | 32091.3779 |
16.6115 | 47.0085 | 275.9419 | 780.8817 |
-15.7085 | 2.0485 | 246.757 | -32.1789 |
4.0115 | 32.8085 | 16.0921 | 131.6113 |
97.7115 | 752.2285 | 9547.5372 | 73501.3751 |
-125.5885 | -792.6915 | 15772.4713 | 99552.9364 |
-69.9285 | -438.3115 | 4889.9951 | 30650.4657 |
111.6915 | 1092.5485 | 12474.9912 | 122028.3808 |
-90.7685 | -549.7315 | 8238.9206 | 49898.3037 |
-88.2885 | -492.4915 | 7794.8592 | 43481.3358 |
-40.9085 | -291.1915 | 1673.5054 | 11912.2075 |
38.3715 | 398.8485 | 1472.372 | 15304.4152 |
-52.4685 | -527.9315 | 2752.9435 | 27699.7739 |
23.5315 | 172.7485 | 553.7315 | 4065.0313 |
SS: 124951.7975 | SP: 906933.1049 |
Sum of X = 6979.54
Sum of Y = 36723.66
Mean X = 174.4885
Mean Y = 918.0915
Sum of squares (SSX) = 124951.7975
Sum of products (SP) = 906933.1049
Regression Equation = ŷ = bX + a
b1 = SP/SSX =
906933.1/124951.8 = 7.2583
b0 = MY - bMX = 918.09 -
(7.26*174.49) = -348.3921
ŷ = 7.2583X - 348.3921
b. b0= -348.3921, b1=7.2583
c. For every increase in x, there is corresponding 7.2583 increase in y
For x=0, y=-348.3921
d. For x=150,
ŷ = (7.2583*150) - 348.3921=740.3529
e.