8.1 The number of drivers is usually much greater between 5 and 6 P.M. (rush hour) than between 1 and 2 P.M. Thus, we would expect the number of accidents to be greater between 5 and 6 P.M. than between 1 and 2 P.M. It is therefore not surprising that the number of traffic accidents attributed to driver fatigue was greater between 5 and 6 P.M. than between 1 and 2 P.M. This is an example where the proportion of accidents attributed to driver fatigue is a more valid measure than the actual count of accidents.

8.2 Although In-N-Out Burger was rated first both times, there may be some reliability concerns since the same restaurant (Five Guys Burger and Fries) received drastically different ratings between 2011 (third) and 2014 (seventh).