Pearson Edexcel Level 3 GCE..Statistics Advanced PAPER 2: Statistical Inferenc. THE PREDICTOR,. RATE YOURSELF FOR EXAMS.

1 Ramon is conducting a research project. He has taken a random sample of 16 pairs of values for (x, y). He has then calculated, from his data, a sample Pearson’s product moment correlation coefficient of 0.716 Ramon ...

1 Ramon is conducting a research project. He has taken a random sample of 16 pairs of values for (x, y). He has then calculated, from his data, a sample Pearson’s product moment correlation coefficient of 0.716 Ramon believes that this calculated figure indicates that the population Pearson’s product moment correlation coefficient is significantly different from zero. (a) Conduct a hypothesis test to investigate Ramon’s belief. (4) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ ___________________________________________________1 Ramon is conducting a research project. He has taken a random sample of 16 pairs of values for (x, y). He has then calculated, from his data, a sample Pearson’s product moment correlation coefficient of 0.716 Ramon believes that this calculated figure indicates that the population Pearson’s product moment correlation coefficient is significantly different from zero. (a) Conduct a hypothesis test to investigate Ramon’s belief. (4) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ ___________________________________________________V1 Ramon is conducting a research project. He has taken a random sample of 16 pairs of values for (x, y). He has then calculated, from his data, a sample Pearson’s product moment correlation coefficient of 0.716 Ramon believes that this calculated figure indicates that the population Pearson’s product moment correlation coefficient is significantly different from zero. (a) Conduct a hypothesis test to investigate Ramon’s belief. (4) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ ___________________________________________________ Ramon has also produced a scatter graph from his data, shown in Figure 1. y 0.0 5.0 10.0 15.0 20.0 25.0 30.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0.0 x Ramon’s scatter graph Figure 1 (b) With reference to the scatter graph, explain why the conclusion made from the hypothesis test conducted in (a) may not be valid. (2) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ ______________________________________________________