Question

4. The local association of car salesmen de predict car sales each month (number of units unemployment rate (in percent terms, e.g number of cars sold in this city du clation of car salesmen develop a linear regression equation to ar sales each month (number of units sold) based on the local e in percent terms, e.g. 7.2%). The following data represents the cars sold in this city during these months, with the local unemployment rate. Y2 = 338150 X = 51 2 Y = 1520 n = 7 EX2 = 374.18 XY = 10962 a. Calculate the slope of the linear regression line for this data. (9 pts) b. What is the value of the sum of squares total? (4 pts) C. Develop the appropriate ANOVA table. (10 pts) d. What is the value of the standard error of the estimate? (6 pts)

Answer 1

Saf 21-1520 Σγ. - 3381 50 ΣΧ- SI Ex374.18 ZXy 10962 a) slofhe of linta aghesion eguatin is given by n(ΣΥ) - (Σ) (zy) η (Σx) -(Σx) 7 (10962) - (s1)(1520) (374-18) - (51) slofte -43- 0449 bTotal Sum Szuales d Sum nahes ΣΟ3 Ey-(Zy) tatal : SST n/zs)-(z9* 33gis0)-(is20) : 56650 SST Scanned with CS CamScanner

ANOVA table Source of vodiatior df fF SS SsR Regieesion ss mSE SE MSE n-2 n-2 Iotal n- SST SsR=P,SSay SSay= 2 (x-z)(1-7) =n(zx) -(zx)(zy) (10962)511520) 2 -786 ssk SSy - -43.04 9 x - 786 SSR = 338 33.3 .SSE SST- SSK 56650-33833-3 SSE 22 S 6.7 Sorrce of df SS vadialion MS Righeysion 33833-3 33833.3 7.G141 2 2816-7 4563.341 s etahed ith6 Camscantrer os 995

d Standad ellA of eytimate SSE Syx n-2 2 2816.7 Sya 67 5525 Scanned with CS CamScanner