每日一题

Mathematics

A restaurant chain with 8 locations wants to introduce healthier options to its menu. In order to determine customer preferences, the chain will offer three new healthy options for a two-week period at all of it's locations and analyze the percent of total orders that include at least one of the new healthy options. Which of the following research designs is most likely to produce valid results?

A.Recording how many customers ordered each of the new options at all of the restaurants over the two-week period
B.Asking a random sample of customers at all of the restaurants which new item they might order in the future
C.Recording how many customers ordered each of the new options at one of the restaurants over the two-week period
D.Recording how many customers ordered each of the new options for breakfast at all of the restaurants over the two-week period

答案和解析

答案：D

解析：

Choice A is correct.

Asking customers which new option they might order in the future does not determine actual customer preferences. One restaurant may not be representative of the entire chain. Some of the new options may be more appropriate for lunch or dinner. Therefore, the following are less likely to produce valid results:

Asking a random sample of customers at all of the restaurants which new option they might order in the future.

Recording how many customers ordered each of the new options in one of the restaurants over the two-week period.

Recording how many customers ordered each of the new options for breakfast in all of the restaurants over the two-week period.