An article contained the following observations on degree of polymerization for

Question

An article contained the following observations on degree of polymerization for paper specimens for which viscosity times concentration fell in a certain (a) Construct a boxplot of the data. Comment on any interesting features. (Select all that apply.) There is little or no skew. The data appears to be centered near 428. There is one outlier. There are no outliers. The data is strongly skewed. The data appears to be centered near 438. (b) Is it plausible that the given sample observations were selected from a normal distribution? Yes No (c) Calculate a two-sided 95% confidence interval for true average degree of polymerization. (Round your answers to two decimal places.) (430.59, 445.65)

Explanation / Answer

Using excel function =AVERAGE(417,421,421,423,425,428,430,434,436,438,445,447,448,452,456,463,464), we get

Mean=438.12

Using excel function =stdev(417,421,421,423,425,428,430,434,436,438,445,447,448,452,456,463,464), we get

Standard deviation s=15.10

Sample size n=17

degree of freedom=n-1=17

Critical t at 5% level=2.120 using excel function =tinv(0.05,16)

So, 95% confidenc interval=Mean-2.120*s/sqrt(n) , Mean+2.120*s/sqrt(n)

=438.12-2.120*15.10/sqrt(17) , 438.12+2.120*15.10/sqrt(17)

=(430.36,445.88)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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