Self-study
A transit company's bus drivers are evaluated by supervisors riding with each driver. ███████ ████████ ████ ████ ███████ █████ ████████████ ███ ███████ ███ ████████████ ████████ ███████ █████ ████████ ████████████ █████ ███████ ██████████ ████ ████ █ ██████████ ██████ ████ ██████ ████ ██ ███ ████ ███████ █████ ██████ ███████████
Summary
The author concludes that having supervisors observe bus drivers provides an accurate assessment of their skills, despite complaints that it negatively impacts performance. This is because the presence of a supervisor hurts the performance of all drivers.
Notable Assumptions
The author is assuming that all drivers are impacted the same amount by the supervisor. If the best driver is impacted by 90% and some other driver only by 5%, then it’s possible that the worse driver could be evaluated higher. This would lead to an inaccurate assessment, so it is necessary to assume that all drivers are impacted in equal amounts.
6.
Which one of the following ██ ██ ██████████ ██ █████ ███ ████████ ████████
a
There is no █████████ ███ ██ ██████████ ███ ███ ████████ ███████████ ███████ ██████ ███████████ ████ ████ █████
The argument only concludes that the method of assessment using supervisors is accurate, and is unconcerned with other methods. The presence or absence of other successful methods would tell us nothing about the supervisor method, so (A) is not necessary.
b
The supervisors are █████████ ██████ ██ █ ███ ████████ ████████████
(B) would strengthen the argument, but it is too strong to be necessary. Even if the supervisors are only good judges instead of excellent, they very well could provide an accurate assessment.
c
For most bus ████████ ███ ████████ ██ █ ██████████ █████ █████ ███████████ ████████ █████ ████ ██ █████████ █████ ███
As long as all drivers are affected equally, we don’t care how much that effect is. If they’re all affected greatly, for example, the argument is still completely fine.
d
The bus drivers ███ ████ ████████ ██ ███████ ███ ████ ███ ███ ██ ███ ████ ██████ ██ ███ ████████ ██ ███ ███████████
If D is not true, and each driver is affected in different amounts, then the supervisors will not get an accurate assessment of each driver’s skills, undermining the conclusion.
e
The bus drivers ██████████ ███ ████ ██ ███████ ████████ ███████████ ██ █████ ███████ ████████████
The argument only concludes that the method of assessment using supervisors is accurate, and is unconcerned with other methods. The presence or absence of other successful methods would tell us nothing about the supervisor method, so (E) is not necessary.