A research trial investigates the effectiveness of a new wearable acoustic device, 'FocusWave', designed to improve deep concentration levels in stock traders during high-volatility trading hours.
Explain one limitation of asking the stock traders to self-report their concentration levels when using 'FocusWave'.
38 exam-style questions on AQA A Level Psychology Self-report techniques. Each one has a worked solution and a mark scheme showing where the marks go.