In: Statistics and Probability
A math teacher claims that she has developed a review course that increases the scores of students on the math portion of a college entrance exam. Based on data from the administrator of the exam, scores are normally distributed with mu equalsμ=524. The teacher obtains a random sample of 2000 students, puts them through the review class, and finds that the mean math score of the 2000 students is 529 with a standard deviation of 119.
Complete parts (a) through (d) below.
(a) State the null and alternative hypotheses. Let muμ be the mean score. Choose the correct answer below.
A.Upper H 0 : mu greater than 524H0: μ>524,
Upper H 1 : mu not equals 524H1: μ≠524
B.Upper H 0 : mu equals 524H0: μ=524,
Upper H 1 : mu greater than 524H1: μ>524
C.Upper H 0 : mu less than 524H0: μ<524,
Upper H 1 : mu greater than 524H1: μ>524
D.Upper H 0 : mu equals 524H0: μ=524,
Upper H 1 : mu not equals 524
(b) Test the hypothesis at the alpha equalsα=0.10 level of significance. Is a mean math score of 529 statistically significantly higher than 524? Conduct a hypothesis test using the P-value approach. Find the test statistic.
Find the P-value.
Is the sample mean statistically significantly higher?
(c) Do you think that a mean math score of 529 versus 524 will affect the decision of a school admissions administrator? In other words, does the increase in the score have any practical significance?
(d) Test the hypothesis at the alphaαequals=0.10 level of significance with nequals=375 students. Assume that the sample mean is still 529 and the sample standard deviation is still 119.Is a sample mean of 529 significantly more than 524? Conduct a hypothesis test using the P-value approach.
Find the test statistic.
Find the P-value.
Is the sample mean statistically significantly higher?
What do you conclude about the impact of large samples on the P-value?
A.As n increases, the likelihood of rejecting the null hypothesis increases. However, large samples tend to overemphasize practically significant differences.
B. As n increases, the likelihood of not rejecting the null hypothesis increases. However, large samples tend to overemphasize practically insignificant differences.
C.As n increases, the likelihood of not rejecting the null hypothesis increases. However, large samples tend to overemphasize practically significant differences.
D.As n increases, the likelihood of rejecting the null hypothesis increases. However, large samples tend to overemphasize practically insignificant differences.