Question

You take a new job where you need to arrive by bus in 30 minutes. There are two buses available to you. The first is a bus that makes all the local stops. This local bus is quicker if there are just a few people. The second is an express bus that drops you off a few blocks from your job. You try both buses the first week of your job. With the local bus you get to work in 20 minutes, 30 minutes, and 45 minutes. The express bus always gets you to work in 35 minutes. What is the data challenge with these two buses? Select an answer:

a. The express bus does not have a data challenge, but the local bus does.
b. The local bus has a high variance, and the express bus has a high bias.
c. The local bus has a high bias, and the express bus has a high variance.
d. Both buses will work for you to get to your job on time.

Answer 1

Option b, the local bus exhibits high variance due to inconsistent travel times, while the express bus shows high bias since it consistently takes longer than the desired 30-minute travel time.

Step-by-step explanation:

To determine the data challenge between the local bus and the express bus, we need to consider consistency and reliability in terms of travel time. The local bus times are 20 minutes, 30 minutes, and 45 minutes, showing a high degree of variability or variance in travel time. On the other hand, the express bus always takes 35 minutes, which is consistent but not within the desired 30-minute timeframe, indicating a likely systematic issue known as bias. Although the express bus is not as fast as needed, its travel time does not vary. Hence, the answer to the question is:

b. The local bus has a high variance, and the express bus has a high bias.