The mean OC for th 31 studdents in Ex 6.6 was 33.4 ng/ml. In our calcs, we assum

Question

The mean OC for th 31 studdents in Ex 6.6 was 33.4 ng/ml. In our calcs, we assumed that the standard dev was known to be 19.6 ng/ml. Use the 68-95-99.7 rule to find the approx bounds on the values of OC that would include those percents of the population. If the asumed standard dev is correct, it would appear that this distribution may be highly skewed. Why? (Hint: The measured values fora variable such as this are all positive.) Do you think that this skewness will invalidate the use of the normal confidence interval in this case? Explain answer.

Explanation / Answer

This distribution is moderately skewed. This is because using the68-95-99.7 rule you would expect data on both sides most likely 3deviations away. If you multiply the st. dev by 2. so 19.6(2) you get 39.2 the mean(33.4) minus the 2 deviations equals -5.8. They stated in the problem that all answers are positive, thereforethere are no negative values. This means that there is no values in the distribution over or evenat 2 deviations below the mean. This skewness will not invalidate the confidence interval becausethe sample size is greater than 25. Therefore the sample mean can overcome light to moderateskewness. I hope this helps. Message me if you have any questions about whatI wrote.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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