A researcher wants to examine the effect of fertilizer and the effect of sunlight on the yield of tomatoes.She bought 60 tomato plants at a local garden store.She randomly assigned 30 tomato plants to be planted on the sunny side of the hill and 30 to be planted on the shady side.Within each group of 30 plants,she randomly assigned plants to one of three groups.The first group is grown with no fertilizer,the second group with a small amount of fertilizer,and the third group with a large amount of fertilizer.All tomato plants are planted at the same time and each plant is grown to maturity.The total weight of tomatoes obtained from each plant is recorded.The person evaluating the results does not know which tomatoes received fertilizer or which were grown on the sunny side.
A)Single blind
B)Double blind
C)Neither

Question

Quizplus · Accepted Answer

The study is single blind because the person evaluating the results does not know which treatment each plant received, but it does not mention that the participants (in this case, possibly the person applying the treatments) are blinded to the treatment groups.

A Researcher Wants to Examine the Effect of Fertilizer and the Effect