商务统计课后习题答案.pdf
50.a.x=6.805y=14.1SharesSellingExpected(Xi)Price(Yi)Xi-XYi-Y(Xi-X)2(Xi-X)(Yi-Y)515-1.8050.93.258025-1.62459142.195-0.14.818025-0.21956.715-0.1050.90.011025-0.09458.75171.9452.93.7830255.6405311-3.805-3.114.4780311.795513.6196.7954.946.17202533.29554.613-2.205-1.14.8620252.42556.714-0.105-0.10.0110250.0105310-3.805-4.114.47802515.60057.7130.895-0.90.801025-0.8055T o tals68.0514192.6722566.024bl=E(Xi-X)(Yi-Y)/E(Xi-X)2=66.024/92.67225=.71b0=y-bl X=14.1-.71*6.805=9.26Ay=9.26+.71xb.F Test:Ho：B =0Ha:Bi WOASSR=E(yi 7)2=46.7168ASSE=(y i-y)2 =16.11689525MSR=SSR/Regression degrees of freedom=46.7168/1=46.7168MSE=SSE/n-2=16.11689525/8=2.0146F=MSR/MSE=23.189Fa=5.32FSo reject Ho,the relationship is significant.c.SSR=46.7168SST=62.9r2=SSR/SST=46.7168/62.9=.74So its good fit.d.y=9.26+.71xWhen x=6,y=13.5352.x=.89y=1.12S&P500HorizonXi-XYi-Y(Xi-X)2(Xi-X)(Yi-Y)1.2-0.70.31-1.820.0961-0.5642-2.5-2-3.39-3.1211.492110.5768-3-5.5-3.89-6.6215.132125.751824.71.113.581.23213.973851.84.110.6816.89212.79481.24.10.312.980.09610.923832.62.111.484.45213.1228-12-1.890.883.5721-1.66320.5-1.3-0.39-2.420.15210.94382.55.51.614.382.59217.0518Total:55.70952.912bl=E(Xi-X)(Yi-Y)/E(Xi-X)2=52.912/55.709=.95bo=y-blx=l.l 2-.95*.89=.2745Ay=0.275+0.95xb.F Test:Ho：3,=0Ha:Bi W OASSR=L(%-7)2=50.255ASSE=Z(yi-yi)=56.781MSR=SSR/Regression degrees of freedom=50.255MSE=SSE/n-2=56.781/8=7.098F=MSR/MSE=7.08Fa=5.32FSo reject Ho,the relationship is significant.c.SSR=50.255SST=SSR+SSE=50,255+56.781=107.036r2=SSR/SST=50.255/107.036=.47So its not good fit.d.Ay=0.275+0.95xTexas Instruments has a higher risk.53.a.Satisfaction Rating(%)b.The relationship is positive,c.x=43.92307692y=65.92307692TopS atisfactionFive(%)R ating(%)Xi-XYi-Y(Xi-X)2(Xi-X)(Yi-Y)3049-13.923-16.923193.8499235.61893864-5.923-1.92335.0819311.389934067-3.9231.07715.38993-4.225074069-3.9233.07715.38993-12.0711558611.07720.077122.6999222.3929608516.07719.077258.4699306.700948744.0778.07716.6219332.929933343-10.923-22.923119.3119250.387946662.0770.0774.3139290.15992950706.0774.07736.9299324.775934253-1.923-12.9233.69792924.8509347623.077-3.9239.467929-12.07114269-1.9233.0773.697929-5.91707T o ta l:834.92311074.923bl=E(Xi-X)(Y i-Y)/L(Xi-X)2=1074.923/834.9231=1.29bO=y-b 1 X=65.923-1.29*43.923=9.26y=9.26+1.29xd.F Test:Ho:3,=0Ha:Bi WOSSR=(y i-y)2=1389.396ASSE=(y;-yi)2=483.0171MSR=SSR/Regression degrees of freedom=1389.396MSE=SSE/n-2=483.0171/11=43.91F=MSR/MSE=31.642Fa=4.84FSo reject H(),the relationship is significant.SSR=1389.396SST=SSR+SSE=1389.396+483.0171=1872.413r2=SSR/SST=1389.396/1872.413=.742So its good fit.f.r=.86155.x=35y=17xiYiXi-XYi-Y(Xi-X)2(Xi-X)(Yi-Y)2021-154225-602019-152225-3040155-225-103016-5-1255601425-3625-75401750250T otal:1150-170bl=L(Xi-X)(Yi-Y)/Z(Xi-X)2=-170/1150=-0.148b0=y-b lx=17+.l 48*35=22.18y=22.18-0.148xb.SSR=25.1896SSE=8.8696MSR=SSR/Regression degrees of freedom=25.1896MSE=SSE/n-2=8.8696/4=2,2174F=MSR/MSE=25.1896/2.2174=11.36Fa=7.71FSo reject Ho,the relationship is significant.C.SSR=25.1896SST=SSR+SSE=25.1896+8.8696=34.06r2=SSR/SST=25.1896/34.06=.74So its good fit.d.x=50Ay50=14.78Ta/2=12.22Sy50=
