Q17: The statistical decision is to fail to reject the null, and Ho is really fa

Question

Q17: The statistical decision is to fail to reject the null, and Ho is really false (ie a Type II error) 0. 4o A researcher wants to determine whether high school students who attend an SAT preparation course score significantly different on the SAT than students who do not attend the preparation course. For those who do not attend the course, the population mean is 1050 (H 1050). The 16 students who attend the preparation course average 1150 on the SAT, with a ation of 100. On the basis of these data, can the researcher conclude that the preparation course has a significant difference on SAT scores? Set alpha equal to.01. 024: What is the z-value or t-value you obtained (your test statistic)? 025: Based on your results (and comparing your Q24 and Q22 answers) would you A. reject the null hypothesis B. fail to reject the null hypothesis 026: The best conclusion for this example would be A. There is no statistical difference in SAT scores when comparing students who took the SAT prep course with the general population of students who did not take the SAT prep course B. There is a statistical difference in SAT scores when comparing students who C. The students who took the SAT prep course did not score significantly higher D. The students who took the SAT prep course did score significantly higher on took the SAT prep course with the general population of students who did not take the SAT prep course on the SAT when compared to the general population of students who did not take the SAT prep course the SAT when compared to the general population of students who did not take the SAT prep course. Based on your evaluation of the null in Q25 and your conclusion is Q26, as a researcher you would be more concermed with a 027: Type I statistical error Type II statistical error

Explanation / Answer

Question 24

Here, we have to use one sample t test for population mean.

The null and alternative hypotheses for this test are summarised as below:

H0: µ = 1050 versus Ha: µ ? 1050

This is a two tailed test.

From given information, we have

Xbar = 1150, S = 100, n = 16, ? = 0.01, df = n – 1 = 16 – 1 = 15

Critical t value = -2.9467 and 2.9467

(by using t-table and df)

Test statistic formula is given as below:

Test statistic = t = (Xbar - µ)/[S/sqrt(n)]

Test statistic = t = (1150 – 1050)/[100/sqrt(16)]

Test statistic = t = 100/25 = 4

Required t-value = 4.00

Question 25

By using above test result,

P-value = 0.0012

(by using t-table)

P-value < ? = 0.01

So, we reject the null hypothesis

Correct Answer: A. Reject the null hypothesis

Question 26

Conclusion:

Here, we reject the null hypothesis of no significant difference. This means there is a significant difference. Test is two tailed. So higher or lower significant differences are not considered for this test. So, correct answer is B.

B.

There is a statistical difference in SAT scores when comparing students who took the SAT prep course with the general population of students who did not take the SAT prep course.

Question 27

Type I error is the probability of rejecting null when it is true. Type II error is do not rejecting null when it is not true. Null hypothesis describes ‘no significant difference’. Actually there is significant difference. If there is significant difference and we do not reject the null hypothesis, then this is a type II statistical error. Answer is B.

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.