A marine biologist is investigating the effect of a new nutrient-rich feed on the growth rate of farmed Atlantic salmon. She uses an independent groups design with two separate sea cages: one cage is fed the new formula, and the other is fed standard feed.
Explain why random allocation of the salmon fingerlings to the two sea cages is necessary in this experimental design.
Practise AQA A Level Psychology Scientific processes with exam-style questions for A Level Psychology. 689 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.
