An agricultural enthusiast claims that playing classical music to strawberry plants improves both the sweetness and the total harvest weight of the fruit.
To test this, he places 12 strawberry plants in his greenhouse. He groups 6 plants on a south-facing shelf near a speaker playing classical music for 8 hours a day (Group A). He places the other 6 plants on a north-facing shelf under a bench where it is quieter and no music is played (Group B). Throughout the summer, he waters all the plants whenever he notices the soil looks dry. At harvest time, he personally picks the strawberries, tastes one from each plant to rate its sweetness on a scale of 1 to 5, and then weighs the total yield of each plant on a digital scale. He finds Group A had higher sweetness ratings and average weight, and concludes his hypothesis is proven.
Explain how this study could be modified to make it more scientific. You should refer to potential methodological criticisms of the current procedure in your answer.
Practise AQA A Level Psychology Scientific processes with exam-style questions for A Level Psychology. 100 questions, matched to the AQA A Level Psychology (7182) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.