Question

A group of researchers is designing an experiment to test whether working late at night reduces a person's productivity. The researchers selected a sample of 60 adults, and over the next month, 30 of them will complete assigned tasks late at night whereas the remaining 30 will complete the same tasks during the afternoon. At the end of the month, the researchers will compare the average amount of time it takes each group to complete the tasks.

Answer 1

Answer:

1, 2, 4

Step-by-step explanation:

Why is it necessary that researchers use randomization to assign each of the adults to a group?

1. randomization ensures each group will be similar in everything except the time of day they are assigned to work
2. randomization prevents the adults from selecting their own group
3. randomization eliminates lurking variables from the experiment
4. randomization prevents the researches from specifically assigning all adults who regularly stay up late to complete assigned tasks late at night
5. randomization ensures that there will an equal number of adults in each group

Randomization ensures that there is no selection bias.