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Chapter 8: Q. T8.3 (page 549)

In preparing to construct a one-sample t interval for a population mean, suppose we are not sure if the population distribution is Normal. In which of the following circumstances would we not be safe constructing the interval based on an SRS of size14from the population?

a. A stemplot of the data is roughly bell-shaped.

b. A histogram of the data shows slight skewness.

c. A boxplot shows that the values above the median are much more variable than the values below the median.

d. The sample standard deviation is large.

e. The sample standard deviation is small.

Short Answer

Expert verified

The required correct option is(c)

Step by step solution

01

Given information

Sample size (n)=14

Confidence interval using t-distribution is to be constructed.

02

Explanation

When the sample size is less than 30and the sample standard deviation is known, the confidence interval using the t distribution is computed. It is also used when data is normally distributed. Because it would show some variability in the data set, a box plot depicting values below and above the median would be inappropriate for constructing the confidence interval.

Therefore, under the circumstances of the box plot, it could be argued that constructing the confidence interval on a sample size of 14is risky.

Hence, the correct option is(c)

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Most popular questions from this chapter

Fun size candyA candy bar manufacturer sells a “fun size” version that is advertised to weigh 17grams. A hungry teacher selected a random sample of 44fun size bars and found a 95%confidence interval for the true mean weight to be 16.945grams to 17.395grams.

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