A consumer magazine wants to compare the lifetimes of ballpoint pens of three di

Question

A consumer magazine wants to compare the lifetimes of ballpoint pens of three different types. The magazine takes a random sample of pens of each type in the following table.

Brand 1: 260 218 184 219

Brand 2: 181 240 162 218

Brand 3: 238 257 241 213

1) the critical value of the test statistic at 1% level of significance is:

2) the numerator degrees of freedom equal:

3) the percentage of explained variation is:

4) the total sample size is:

12

16

3

15

5) at a 30% level of significance the decision is:

Fail to reject null hypothesis, means are not different

Reject null hypothesis, means are not different

None of the other choices is correct

Reject null hypothesis, means are different

12

16

3

15

Explanation / Answer

applying one way ANOVA on above test:

1)  critical value of the test statistic at 1% level of significance is =8.0215

2) numerator degrees of freedom equal =2

3) percentage of explained variation is =(SSR/SST)*100 =(2744/10366.25)*100 =26.47%

4)  total sample size is n=16

5) for p value is less then 30%

hence Reject null hypothesis, means are different

Source of Variation SS df MS F P-value Between Groups 2744 2 1372 1.6200 0.2507 Within Groups 7622.25 9 846.917 Total 10366.25 11

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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