An engineering firm is testing a new friction-reducing lubricant designed to increase the operational efficiency of wind turbines. The lead engineer decides to conduct a one-tailed hypothesis test to analyze the efficiency data.
Give one reason why a one-tailed test, rather than a two-tailed test, is appropriate in this situation.
121 exam-style questions on AQA A Level Psychology Inferential testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.