In: Statistics and Probability
***Use R/STATA to perform the following analysis
Data: ShareValue.xlsx contains data on N=309 firms which sold new shares. Data on the following variables is provided. All variables are measured in millions of US dollars. ShrVal is the dependent variable and the all the remaining variables are the explanatory variables.
ShareValue: the total value of all shares outstanding, calculated as the price per share times the number of shares outstanding.
FirmDebt: firm’s long-term debt
TotalSales: sales of the firm.
Net_Income: net income of the firm.
TotalAssets: book value of the assets of the firm
1. Undertake appropriate basic data analytics to motivate the regression model above.
2. Using the dataset provided, run the above described regression model and interpret all regression coefficients.
3. Do you suspect any multicollinearity problem could affect the regression coefficients?
5. Use graphical method or a test of heteroscedasticity to check for evidence of heteroscedasticity in part 2.
6. Test the following hypothesis:
(a) Is your regression model a significant predictor of share value variations for the sample of firms you are given?
(b) Test that increasing sales by 20 million dollars, everything else held constant, would raise the share value by at least 5 million dollars;
(c) Test the fact that jointly, a firm’s total assets and its outstanding debts better left out of this regression (BetaTotAssets = BetaDebt =0)
Use the Breusch-Pagan test to see if there is heteroskedasticity in this regression.
Use the White test to see if there is heteroskedasticity in this regression.
You should have found that heteroskedasticity is present. Using the strategy for "Log transforming the Model" investigate whether using a “double-log model” fixes the heteroscedasticity problem? For your transformed regression, state how the coefficients should be interpreted.
Does dividing the original (“levels”) model’s all variables by the FirmDebt variable fix the heteroskedasticity problem? For your transformed regression, state how the coefficients should be interpreted.
Using heteroskedasticity consistent estimator (HCE or White robust estimator). Estimate the regression model using one HCE.
Of the regressions in questions 9, 10, 11, which would you use as your preferred specification for inclusion for this particular project?
ShareValue | FirmDebt | TotalSales | Net_Income | TotalAssets |
110.8 | 0.4 | 0.1 | -5.9 | 11.8 |
52.7 | 0.3 | 57.6 | 1.3 | 13.4 |
108.8 | 0.4 | 7.6 | -8.4 | 14.3 |
26.9 | 4.7 | 27 | 0.3 | 10.8 |
94 | 72.2 | 163.7 | 3.7 | 131.5 |
252.2 | 4.4 | 82.2 | 4.6 | 16.5 |
42.8 | 2.2 | 44.1 | 1.4 | 24.5 |
42.5 | 13 | 78.9 | 2.8 | 46 |
81.5 | 128.5 | 157.7 | -0.2 | 190 |
472.3 | 283.9 | 1619.3 | 9.2 | 743.5 |
768.8 | 425 | 633.6 | 23.2 | 783.1 |
138.9 | 1.5 | 297.3 | 5.6 | 92.7 |
380.6 | 47 | 144.2 | 28.1 | 118 |
240 | 6.1 | 0.6 | -3.7 | 12.9 |
158.2 | 0.6 | 1.4 | -5.2 | 11.2 |
102.9 | 0.3 | 7.4 | -3.1 | 7.1 |
69.3 | 20.4 | 102.4 | 1 | 64.6 |
59.4 | 2.4 | 33.8 | 2.5 | 27.3 |
72.2 | 0.2 | 68 | 9.4 | 44.6 |
28.4 | 2.6 | 13.2 | 0.5 | 9.9 |
287.8 | 0.5 | 23 | 0.6 | 21.1 |
260.8 | 16 | 63.3 | 7.6 | 47.7 |
82.8 | 7.2 | 96.8 | 6.3 | 49.8 |
18 | 1.6 | 9.3 | 1.3 | 7 |
52.5 | 0.5 | 35.8 | 0.6 | 5.1 |
62.5 | 0.2 | 54.9 | 2.8 | 18 |
75.6 | 0.5 | 16.5 | 0.3 | 17.5 |
77.2 | 0.6 | 10 | -2.1 | 5.4 |
71.3 | 35 | 6.6 | 0.8 | 53.1 |
41.7 | 0.1 | 2.3 | -1.5 | 2.5 |
205.6 | 9.8 | 161.5 | 10.1 | 58.8 |
2623.4 | 968.3 | 175.9 | -61 | 658.9 |
57.7 | 0.4 | 0.6 | -6.4 | 5.9 |
59.6 | 0.1 | 0.3 | -2.8 | 1 |
94.1 | 0.4 | 0.1 | -3.3 | 4.7 |
163.5 | 1 | 16.7 | -6.4 | 26.8 |
64 | 13.4 | 710.8 | 5.3 | 92.9 |
122.9 | 7 | 20.8 | 1.6 | 28.3 |
144.7 | 2.2 | 413.7 | 7.7 | 94.6 |
21.8 | 0.3 | 2.8 | 0.6 | 1.2 |
199.2 | 238.3 | 27.7 | 5 | 525.2 |
186.4 | 1.3 | 92.6 | 7.6 | 122.8 |
55.8 | 0.1 | 14.2 | 1.2 | 7.9 |
304.8 | 2.5 | 0.3 | -6.4 | 15.7 |
13.7 | 0.2 | 21.9 | 0.9 | 9.1 |
17.6 | 1.3 | 13.6 | 1.2 | 4.7 |
112.3 | 2.5 | 30.2 | -0.9 | 13 |
166.6 | 1.4 | 5.5 | -3.7 | 28.1 |
108.1 | 0.7 | 11.1 | -0.3 | 4.5 |
147.5 | 0.1 | 16.7 | 1.2 | 10 |
545.8 | 376.1 | 667.2 | 14.9 | 668.3 |
173.4 | 5.3 | 93.5 | 4.7 | 103.2 |
32.5 | 4 | 36.8 | 1.9 | 22.6 |
61.5 | 0.2 | 30 | -1.8 | 15.9 |
92.2 | 0.3 | 6.7 | -3.6 | 5.7 |
39.6 | 0.6 | 17.7 | 1.4 | 2.9 |
24.8 | 0.6 | 5.5 | 0.5 | 5 |
21.4 | 1.9 | 13.1 | 0.6 | 7.4 |
96.8 | 4 | 28.7 | -0.3 | 57.6 |
68.9 | 5.5 | 26.9 | 0.3 | 21.6 |
120.6 | 14.6 | 119.5 | -0.2 | 106 |
234.4 | 111.8 | 38.1 | -10.7 | 139.8 |
152.1 | 18.1 | 113.5 | 6.1 | 79.4 |
42.2 | 1.1 | 84.3 | 0.9 | 28.2 |
64.8 | 0.2 | 46.4 | 2.3 | 19.5 |
92.8 | 25 | 127.6 | 8.6 | 70.3 |
120.6 | 0.2 | 0.3 | -5.2 | 7.5 |
95.8 | 0.7 | 15 | -10.1 | 9.3 |
174.2 | 125.7 | 74.7 | 2.8 | 138.2 |
161 | 2.9 | 50.5 | 2.3 | 25.5 |
304.9 | 0.4 | 22.3 | 1.9 | 17 |
56.2 | 0.2 | 0.2 | -3.4 | 3.6 |
361.3 | 0.3 | 34.9 | -1.1 | 22.7 |
37 | 0.4 | 61.4 | 1.9 | 22.5 |
116.9 | 35 | 131 | 21.2 | 87.4 |
43.5 | 0.3 | 1.7 | 0.2 | 14.4 |
534.9 | 1.3 | 93.6 | -1.2 | 58.1 |
386.1 | 49.1 | 96.4 | -15.4 | 104.8 |
253.1 | 4.9 | 44 | 2 | 34.5 |
184.7 | 0.7 | 15.4 | 0.8 | 11.3 |
168.3 | 2.6 | 130.5 | 1.4 | 34.9 |
120 | 1.1 | 239.4 | 0.8 | 17.8 |
1734 | 0.3 | 718.7 | 73.2 | 301.9 |
162.9 | 36.1 | 21.2 | 9.4 | 87.4 |
231.8 | 231.2 | 53 | -64.3 | 310.6 |
788.2 | 360 | 77 | 36.1 | 1077.9 |
206.9 | 94.3 | 657.3 | 8 | 275 |
145.4 | 1.9 | 18.1 | 7.3 | 21.2 |
749.3 | 258 | 122.9 | -58.2 | 468.7 |
76 | 1.3 | 11.2 | -4.2 | 8.9 |
509.9 | 10.3 | 270.7 | 8.4 | 157.2 |
87.2 | 29.5 | 6.7 | 5.1 | 59.8 |
468.1 | 493.5 | 359.7 | 13.5 | 306.5 |
2682.8 | 96.8 | 207.2 | 14.3 | 231.1 |
166.7 | 49.4 | 27.3 | 11.6 | 124 |
244 | 3.6 | 54.9 | 5.5 | 57.6 |
173 | 16.5 | 17.5 | -9.7 | 40.3 |
242.6 | 80.4 | 21.8 | 12.9 | 204.7 |
112.6 | 237.1 | 51.1 | 3.2 | 288.6 |
828.5 | 451.6 | 5006.4 | 33.4 | 1083.1 |
884.2 | 442.3 | 127.3 | 1.2 | 1619.2 |
151.5 | 267.1 | 81.3 | 18.1 | 455.7 |
436.8 | 0.3 | 42.7 | 3 | 55.7 |
67.6 | 0.1 | 83 | 4.1 | 44 |
82.6 | 0.2 | 80.2 | 3.8 | 56.9 |
616.4 | 0.3 | 118.2 | 10.9 | 142.2 |
242.7 | 0.3 | 62.2 | 11.8 | 1231.1 |
296.5 | 0.4 | 0.9 | -6.9 | 36 |
1622.2 | 0.4 | 377.8 | 51.3 | 370.5 |
53.8 | 0.7 | 0.2 | -6.1 | 3.9 |
374.2 | 0.8 | 21.2 | -3.9 | 42.9 |
466.7 | 0.8 | 81 | -17.2 | 103.5 |
359.7 | 0.9 | 171.2 | -4.6 | 171.6 |
1132.6 | 1.5 | 75.6 | 19.5 | 136.4 |
891.9 | 2.5 | 253.4 | 11.2 | 128.8 |
338.2 | 2.7 | 63.8 | -1.6 | 58.8 |
186.7 | 2.8 | 10.8 | -6.1 | 48 |
68.7 | 2.8 | 4 | 1.4 | 52.8 |
605.8 | 3.3 | 41.6 | 9 | 92.6 |
942.8 | 6.7 | 147.8 | 11.7 | 192.8 |
366.5 | 7.6 | 119.3 | 22.7 | 157.5 |
334.8 | 9.5 | 20.2 | 0.9 | 302.8 |
1655.3 | 14.8 | 609.8 | 12.4 | 141.7 |
133.9 | 17.4 | 94.3 | 4.8 | 92.5 |
495.7 | 29.6 | 287.1 | 14.6 | 258.9 |
194.3 | 35.5 | 351.9 | 17.4 | 225.7 |
1516.7 | 41.8 | 1.1 | 0.6 | 579.2 |
856.4 | 55.9 | 135.1 | 8.7 | 210.4 |
458.3 | 100 | 293.8 | 23 | 192.6 |
2058.3 | 111.6 | 1085.8 | -50.2 | 639.8 |
75.4 | 137 | 17.5 | 4.4 | 528.2 |
318.9 | 137.3 | 84.1 | 17.1 | 242.7 |
312.1 | 142.6 | 96.2 | -6.5 | 235.3 |
681.8 | 178.9 | 387.7 | 33.7 | 416.8 |
760 | 180.7 | 1041.2 | 21.7 | 741.9 |
392.3 | 184.3 | 267.3 | 15.1 | 498.5 |
434.7 | 188.5 | 77.4 | 15 | 325.1 |
198 | 192 | 418.2 | 13.9 | 634.1 |
908.9 | 259.2 | 1330.9 | 48.9 | 985.5 |
998.2 | 269.6 | 94.8 | 14.5 | 323.5 |
670.6 | 340 | 1248.8 | 48.2 | 1211.5 |
949.9 | 349.4 | 138.9 | 102.4 | 848.6 |
1005.8 | 373.9 | 545.4 | 26.7 | 734.1 |
975.6 | 409.8 | 131.4 | 35 | 1045.6 |
38396.6 | 1112 | 4937 | 337 | 5469 |
730.6 | 1371.7 | 219.9 | -1.9 | 584.5 |
5722.3 | 1577 | 4109 | 202 | 4134 |
1457.4 | 1836.4 | 869.1 | 96.7 | 3403.1 |
5397.3 | 1940.3 | 16121.5 | 299.7 | 5032.7 |
1486.9 | 2222 | 5905 | 342 | 4821 |
4024.7 | 3523 | 6804 | 259 | 9495 |
5449.9 | 4541 | 5465 | 449 | 11296 |
374 | 345.5 | 81.7 | -21.7 | 233.1 |
2462.5 | 82.5 | 147.7 | 27.1 | 658.2 |
1048.3 | 3.5 | 4.9 | -31.3 | 157.2 |
528.9 | 351.8 | 512.9 | 32.9 | 408.4 |
164.9 | 1.6 | 5.4 | -6.9 | 37.6 |
694.7 | 397.7 | 154.8 | 35.4 | 534.8 |
333.8 | 116.1 | 233.3 | 12 | 251.7 |
312 | 155.2 | 45.9 | 14.4 | 397.4 |
2545.8 | 2004.5 | 2635.2 | -432.3 | 6057 |
215.9 | 4.7 | 0.6 | -12.6 | 26 |
473.5 | 3.4 | 106.3 | 18.4 | 88 |
1567.5 | 384.8 | 735.3 | 66.6 | 1154 |
741.6 | 23.3 | 671.4 | 11.3 | 303.7 |
240.4 | 1.8 | 22.4 | 7.2 | 27.4 |
325.4 | 7.1 | 188.9 | -5.4 | 124 |
259.6 | 121.6 | 170.1 | 22.4 | 1873.8 |
486 | 74.7 | 102.5 | 43 | 911 |
874.9 | 207.3 | 499.4 | 73.1 | 3150 |
672.7 | 0.5 | 176.7 | 14.6 | 108.5 |
991.3 | 12.5 | 205.6 | 19.3 | 244.6 |
1039.5 | 1.5 | 101.7 | 7.5 | 74.3 |
306.5 | 24.5 | 346.3 | 24.5 | 320.5 |
56.3 | 1.5 | 245.9 | 2.1 | 82.4 |
182.5 | 6 | 8.9 | 0.4 | 26.2 |
830 | 310.4 | 982 | 39.1 | 767.9 |
484.8 | 236.6 | 231.8 | 8.3 | 188.3 |
76.2 | 1.8 | 84.9 | 6.1 | 44 |
409.7 | 6.4 | 25.2 | -5 | 55.2 |
79.3 | 23.2 | 156.8 | -5.7 | 127.5 |
501.8 | 86.3 | 432.5 | 9.5 | 206 |
176 | 9.5 | 664.1 | 7.9 | 155.1 |
1064.3 | 15.4 | 60.7 | -32.6 | 147 |
215.3 | 68.8 | 300.2 | -7.2 | 1132.8 |
1886.1 | 222.5 | 807.2 | 61.4 | 660 |
304.1 | 231.8 | 54.5 | 20.1 | 449.5 |
1335.6 | 1338.4 | 3494.3 | 74.4 | 3687.8 |
1571.7 | 0.7 | 11.4 | -23 | 78.1 |
108.9 | 142.5 | 80.7 | 5.9 | 224.1 |
150.5 | 1.5 | 139.7 | 7.1 | 75.3 |
2390.7 | 146.8 | 1047.7 | 85.7 | 1276.5 |
165.2 | 262.5 | 39.8 | 8.2 | 378.5 |
452.4 | 1.3 | 8.8 | -29.4 | 44.9 |
136.1 | 0.1 | 73.8 | 2.8 | 40.2 |
217.7 | 0.5 | 1.3 | -18 | 47 |
252.9 | 1 | 94.8 | 3.9 | 39.4 |
78.1 | 2.6 | 0.9 | -10.2 | 17.4 |
88.8 | 0.2 | 22.7 | 2.5 | 73.1 |
7415.8 | 554.4 | 763.3 | 142.7 | 1398.1 |
156.4 | 4.2 | 19.2 | 2 | 48.7 |
1318.8 | 24 | 510.6 | 48.7 | 1792.2 |
233.2 | 105.1 | 84.1 | 1 | 354.2 |
389.1 | 63.4 | 188.2 | 17 | 268 |
3201.6 | 466.2 | 317.8 | 25.1 | 595 |
312.9 | 38.3 | 119.7 | 4.9 | 181 |
1080 | 154.4 | 234.4 | 14.2 | 355.1 |
495 | 25.9 | 890 | 18.4 | 363.8 |
182.2 | 134.3 | 532.4 | 11.6 | 305.6 |
835.7 | 57.7 | 496.6 | 18.8 | 305.7 |
1626 | 82.7 | 399.6 | 24.8 | 360.8 |
609.4 | 8 | 183 | 10.8 | 196 |
988.2 | 335.9 | 201 | 24 | 447.3 |
482.5 | 2 | 2.7 | -10.2 | 27.3 |
1111.2 | 375.4 | 353.4 | 12.6 | 755.6 |
927.6 | 42.1 | 336.5 | 21.6 | 173.6 |
52.3 | 0.9 | 5.1 | -6.1 | 13.3 |
123 | 123.1 | 55.9 | -16.7 | 178.7 |
567.8 | 315.3 | 133 | -3.4 | 466 |
236.2 | 0.5 | 110 | -32.7 | 72.7 |
266.7 | 26.5 | 37.4 | 17.6 | 225.1 |
763.1 | 243.2 | 388.2 | 38.5 | 295.8 |
188.3 | 7.8 | 328.7 | 8.9 | 152.9 |
790.4 | 344.4 | 442 | 26.6 | 1064.8 |
570.5 | 2384 | 565 | -82 | 3557 |
1442.9 | 354.1 | 2732.1 | 101.1 | 1213.7 |
2418.3 | 0.4 | 51.7 | -3.8 | 122.2 |
1072.7 | 118.5 | 949.8 | 78.7 | 7594.8 |
87.2 | 9.4 | 97.5 | 2.9 | 42.9 |
466 | 9.7 | 41.8 | -11.5 | 100.3 |
608.5 | 16 | 350.9 | 20.3 | 254 |
308 | 1.8 | 104.9 | 7 | 40.6 |
953 | 116.5 | 3155 | 35.4 | 558.8 |
315.7 | 9.7 | 132.9 | 16.1 | 119.4 |
416 | 2295 | 130.6 | 9.6 | 137 |
276.7 | 241.4 | 157.9 | -25.4 | 230.8 |
221.6 | 10.1 | 40.4 | 1.5 | 38.7 |
83.1 | 20.2 | 38.7 | 10.6 | 133.5 |
137.3 | 57.8 | 70.2 | -8.4 | 139.5 |
167.7 | 210 | 83.1 | 11.4 | 277.2 |
277.7 | 163.7 | 1082.2 | 16.1 | 379.1 |
353.9 | 70 | 155.9 | 27.2 | 687.5 |
643.3 | 0.2 | 0.5 | -11.7 | 11.3 |
171.9 | 0.5 | 22.5 | 2.2 | 31.5 |
305.6 | 42.4 | 21.8 | 4.9 | 173.4 |
926.2 | 7 | 137.3 | 23.3 | 204.6 |
559.2 | 346.2 | 87.9 | 16.7 | 737.6 |
43 | 0.1 | 16 | 1.9 | 14.6 |
448.1 | 79.8 | 79.5 | 32.8 | 842.6 |
968 | 27.7 | 641.1 | 53.3 | 1130.9 |
712.4 | 68.7 | 209.1 | 17 | 141.4 |
104.9 | 0.6 | 14.9 | -1.4 | 6.8 |
288.3 | 125.2 | 128 | 9.9 | 216.1 |
323.6 | 144.9 | 161.7 | 1.5 | 418371 |
161.3 | 1.6 | 17.3 | 2.2 | 22.8 |
323.9 | 2 | 47.1 | 2.7 | 43.9 |
51.4 | 2.4 | 18.6 | 1.4 | 22.4 |
227.8 | 65.7 | 576.3 | 28.2 | 316.7 |
125.9 | 2.2 | 0.9 | -5.2 | 15.5 |
120.6 | 0.1 | 32.8 | 1.3 | 26.5 |
1415.9 | 2.8 | 83.2 | -2.1 | 64.4 |
456.8 | 0.7 | 57.1 | 3.6 | 108.4 |
324.1 | 282.8 | 729.4 | 17 | 824.2 |
289.8 | 0.4 | 58.5 | 3.5 | 23.2 |
759 | 139.9 | 21.3 | 1.7 | 73.6 |
218.4 | 1.2 | 11.8 | 0.4 | 11.7 |
100.1 | 6.9 | 143.9 | 7 | 36 |
77.3 | 41.2 | 130.4 | 4.2 | 100.3 |
356.4 | 1.2 | 1 | -10.8 | 24.1 |
69.9 | 3.5 | 8.8 | -12.9 | 29.1 |
139.8 | 0.8 | 36.2 | 5.8 | 32.8 |
307.2 | 22.6 | 41.4 | 4.6 | 90.8 |
2047.3 | 143.3 | 78.9 | -57.1 | 260.3 |
53.2 | 7.2 | 22 | 0.6 | 16.5 |
656.3 | 250 | 924.6 | 28.1 | 1512.9 |
167.8 | 0.7 | 9.6 | -3.3 | 10.6 |
1253.1 | 2.9 | 634.5 | 33.1 | 247.5 |
34.8 | 0.1 | 38.2 | -0.6 | 18.1 |
20.7 | 20.1 | 59.6 | 1.3 | 16.4 |
76.4 | 0.8 | 19.9 | -1.4 | 9.4 |
372.7 | 2 | 27.4 | -22.7 | 57.3 |
73.7 | 1.2 | 78.2 | -1.4 | 40.9 |
226 | 0.1 | 25.6 | 3.7 | 24 |
79.2 | 0.9 | 7.2 | 2 | 9.6 |
36.2 | 241.8 | 49.7 | 6.2 | 608.4 |
184.5 | 9.9 | 3.1 | -20.7 | 43.8 |
333 | 5.9 | 819.4 | 6.6 | 259.6 |
67.3 | 1.2 | 10 | -1.9 | 4.3 |
277.2 | 1.5 | 125.4 | -1.5 | 48.9 |
388.2 | 219.9 | 210.5 | -7.6 | 304.7 |
841.6 | 0.1 | 19.7 | 16.9 | 51.3 |
52.3 | 1.6 | 19.7 | -4.4 | 22.4 |
176.4 | 1.1 | 3.8 | -8.7 | 11.6 |
87.6 | 5.1 | 25.4 | 1.3 | 40.7 |
267.4 | 0.1 | 117.9 | -16.4 | 65.1 |
21.7 | 0.8 | 5.8 | -11.3 | 9.8 |
696.7 | 353.9 | 91.3 | -20.1 | 125.9 |
638.4 | 125 | 415.6 | 7.1 | 347.6 |
146.5 | 3.7 | 211.8 | 8.4 | 88.7 |
103.6 | 0.7 | 25.3 | 1 | 12 |
37.1 | 2.1 | 4.6 | -4 | 11 |
219.1 | 48.2 | 306.1 | 10.4 | 167.4 |
138.4 | 1.4 | 1.7 | -5.8 | 22.3 |
257.9 | 0.7 | 69.7 | -8.3 | 79.5 |
4341.6 | 46 | 508.1 | 20.1 | 341.4 |
140.8 | 5.1 | 26.3 | 4.1 | 35.9 |
136.2 | 13.5 | 1034.9 | 4.6 | 281.9 |
73.2 | 0.2 | 5.6 | -5.7 | 4.7 |
219.2 | 2.5 | 31.6 | 4.7 | 59.6 |
1.)
data=read.csv(file.choose())# to read the given data.
y=data$ShareValue # response variable of regression.
x1=data$FirmDebt
x2=data$TotalSales # x1,x2,x3,x4 are the corresponding regressor
variable
x3=data$Net_Income
x4=data$TotalAssets
l=lm(y~x1+x2+x3+x4)
l
Output:
Call:
lm(formula = y ~ x1 + x2 + x3 + x4)
Coefficients:
(Intercept) x1 x2 x3 x4
3.408e+02 1.608e-01 2.984e-01 1.552e+01 1.844e-04
# the value of the coefficients are given in the above.
2.) and 3.)
summary(l)
Output:
> summary(l)
Call:
lm(formula = y ~ x1 + x2 + x3 + x4)
Residuals:
Min 1Q Median 3Q Max
-6282.1 -337.9 -219.5 30.3 31172.3
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 3.408e+02 1.221e+02 2.791 0.00558 **
x1 1.608e-01 3.277e-01 0.491 0.62409
x2 2.984e-01 1.366e-01 2.184 0.02970 *
x3 1.552e+01 2.698e+00 5.753 2.14e-08 ***
x4 1.844e-04 4.838e-03 0.038 0.96962
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 2020 on 304 degrees of freedom
Multiple R-squared: 0.2548, Adjusted R-squared: 0.245
F-statistic: 25.99 on 4 and 304 DF, p-value: < 2.2e-16
## from the above table the if we observe the p-value , then it is clear that when we test the equality of regression coefficients with zero i,e H_o: b_i=0,(where b_i are the four regression coefficients ) then all the test is not significant. star marks(*, **, ***) are significant at level of significance 0.05. Hence, multicolinearity may present into the data set .
## On the other hand presence of multicolinearity can be tested by Condition number= where is the eigen value of the matrix () where is the data matrix . =(FirmDebt,TotalSales,Net_Income,TotalAssets). Multicolinearity present into the dataset if condition no>20.
r-code:
X=cbind(x1,x2,x3,x4)
eigen(t(X)%*%X)
output:
eigen() decomposition
$values
[1] 175539557562 539739405 37893909 559859
$vectors
[,1] [,2] [,3] [,4]
[1,] -1.290562e-03 -0.267242591 0.9633580959 -2.282347e-02
[2,] -2.433285e-03 -0.963218961 -0.2677453013 -2.271050e-02
[3,] -8.054405e-05 -0.027989111 0.0159148032 9.994815e-01
[4,] -9.999962e-01 0.002690944 -0.0005930566 4.213941e-06
### now highest eigenvalu=175539557562 and smallest eigen value= 559859
and condition no =559 which implies presence of multicolinearity.
5.)
Breusch-Pagan test: is given by the plot of residual of the reagression with y variable . If there is a pattern into the graph Heteroscadasticity present into the data set.
## Breusch-Pagan test##
r=resid(l)
plot(r,y)
6.)
a) from the first table we already see that p-value< 0.05.
output:
Residual standard error: 2020 on 304 degrees of freedom
Multiple R-squared: 0.2548, Adjusted R-squared: 0.245
F-statistic: 25.99 on 4 and 304 DF, p-value: <
2.2e-16.
#hence predictor is significant.
b) coefficints of x2=
2.984e-01
hence keeping all unit fixed increase 1 unit sales implies 2.984e-01 unit increse in share value. therefore 20 unit inrease in sale implies 20* 2.984e-01=23(approx).hence increasing sale implies increasing share value at least 5 unit is possible.