Which of the following is true about the P-value? A. The P-value is the probability of seeing the observed result, and results more extreme, by chance alone (given that the null hypothesis is true). B. To calculate the P-value, we need to know whether the hypothesis test is two-tailed or not. C. To calculate the P-value, we do NOT need to know what alpha is. D. All of the above.

4-5 only

Under what circumstances is a t statistic used instead of a z-score for a hypothesis test?     Justin wants to know whether a commonly prescribed drug does improve the attention span of students with attention deficit disorder (ADD). He knows that the mean attention span for students with ADD who are not taking the drug is 2.3 minutes long. His sample of 12 students taking the drug yielded a mean of 4.6 minutes. Justin can find no information regarding σx , so he calculated s2x =1.96. Determine the critical region using a one-tailed test with alpha = .05. Conduct the hypothesis test (Do the math and compare the t-critical and t-obtained values). State your conclusions in terms of H0 (Should you reject the H0 or fail to reject/accept the H0). Based on your analysis, is there a relationship between the drug and attention span?

Help with D & E

CHALLENGE ACTIVITY 402562.2600368.qx3zqy7 8.2.3: Hypothesis testing for two population proportions (one-tailed z-test). Jump to level 1 A university department chair believes that the afternoon section of a large survey class has a consistently lower proportion of students that pass the class compared to the morning section. The chair checks a random sample of student records from each section. The results of the data collected are shown below. Morning section Afternoon section Successes Observations p-hat_1 346 Successes 400 Observations 0.865 p-hat_2 Confidence level 95% -0.5548 p-value 0.2912 3 2 6 2 P= Ex 1.234 Morning section samples: ₁ Ex: 9 Afternoon section samples: 1₂ Sample proportion for morning section samples: p1 Sample proportion for afternoon section samples: p₂ – O 500 LE E 2 № 7 || ||| Ex: 1.234 D D DO