In a bumper test, three test vehicles of each of three types of autos were crashed into a barrier at 5 mph, and the resulting damage was estimated. Crashes were from three angles: head-on, slanted, and rear-end. The results are shown below.Research questions:Is the mean repair cost affected by crash type and/or vehicle type? Are the observed effects (if any) large enough to be of practical importance (as opposed to statistical significance)?

5 mph Collision Damage ($)
Crash Type	Goliath	Varmint	Weasel
Head-On	770	1,760	2,270
Head-On	1,430	1,670	1,620
Head-On	830	1,650	1,720
Slant	1,410	1,830	2,010
Slant	1,770	1,710	1,540
Slant	1,200	1,610	2,440
Rear-end	740	800	1,650
Rear-end	1,200	1,590	1,620
Rear-end	990	1,230	1,230

(a-1)Choose the correct row-effect hypotheses.

a.H₀:A₁?A₂?A₃? 0??Angle means differ

H₁: All theA_jare equal to zero??Angle means are the same

b.H₀:A₁=A₂=A₃= 0??Angle means are the same

H₁: Not all theA_jare equal to zero??Angle means differ

multiple choice 1

• b
• a

(a-2)Choose the correct column-effect hypotheses.

a.H₀:B₁?B₂?B₃? 0??Vehicle means differ

H₁: All theB_kare equal to zero??Vehicle means are the same

b.H₀:B₁=B₂=B₃= 0??Vehicle means are the same

H₁: Not all theB_kare equal to zero??Vehicle means differ

multiple choice 2

• A or B

(a-3)Choose the correct interaction-effect hypotheses.

a.H₀: Not all theAB_jkare equal to zero??there is an interaction effect

H₁: All theAB_jkare equal to zero??there is no interaction effect

b.H₀: All theAB_jkare equal to zero??there is no interaction effect

H₁: Not all theAB_jkare equal to zero??there is an interaction effect

multiple choice 3

• a or b

Fill in the missing data.

Table of Means Factor 2 (Vehicle) Factor 1 (Angle) Goliath Varmint Weasel Total Head-On Slant Rear-End Total Two-Factor ANOVA with Replication Source SS df MS F p-value Factor 1 (Angle) Factor 2 (Vehicle) Interaction Error Total