A criminological psychologist investigated whether the presence of a visible weapon affected the number of correct details recalled by eyewitnesses. She conducted a Mann–Whitney U test on her data. The calculated/observed value of U U\,U was 14, and the critical value of U U\,U for a two-tailed hypothesis at p≤0.05 p \le 0.05\,p≤0.05 was 19.
Determine whether the psychologist's results are statistically significant.
51 exam-style questions on Edexcel A Level Psychology Research methods and skills, covering Research methods and skills. Each one has a worked solution and a mark scheme showing where the marks go.