# Statistics

The head librarian claims that books have been checked out an average of seven times in the last year.

You suspect she has exaggerated the checkout rate and that the mean number of checkouts per book per year is, in fact, less than seven.

Using the computerized card catalog, you randomly select one book and find that it has been checked out four times in the last year. Assume that the standard deviation of the number of checkouts per book per year is approximately 0.90.

If the mean number of checkouts per book per year is seven, as the librarian claims, would you consider a value of 4 checkouts per year to be an outlier?

Is the x value of interest more than 3 standard deviations below the mean or is it 3 st deviations above the mean?

Or is the x-value not an outlier?

1. 👍 0
2. 👎 0
3. 👁 266
1. First of all, what criterion are you using to identify an outlier?

If it is Z = ±3, then this book would be an outlier. For outliers, it is a two-tailed test, you are interested in extremely deviant scores both above and below the mean.

I hope this helps. Thanks for asking.

1. 👍 0
2. 👎 0
2. Thanks. Would that mean the initial claim was too high?

1. 👍 0
2. 👎 0
3. *librarians intial claim

1. 👍 0
2. 👎 0
4. Among the thousands of books that are checked out, the one outlier would have a minimal effect, if at all. This is inadequate evidence to respond to the librarian's sstatistic.

To test the The Ho that μ = 7 against the alternative hypothesis that μ < 7, a larger sample is needed to compare the sample mean to the librarian's estimate.

I hope this helps a little more. Thanks for asking.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### English

Read the excerpt from “A Poem for My Librarian, Mrs. Long.” And Mrs. Long opened that wardrobe But no lions or witches scared me I went through Knowing there would be Spring Why does the poet most likely include this allusion

2. ### math

Textbook prices have a seasonal structure on Ebay. At the end of a term, the supply of used books outstrips demand, and the price is lower. Near the start of a term, many students are looking for books, and the price is higher.

3. ### math-distinguishability

A library has six identical copies of a certain book. At any given time, some of these copies are at the library and some are checked out. How many different ways are there for some of the books to be in the library and the rest

4. ### Physics

The speed of the head of a redheaded woodpecker reaches 3.4 m/s before impact with the tree. The mass of the head is 0.060 kg and the average force on the head during impact is 5.0 N. a)Find the acceleration of the head (assuming

1. ### MATH

Sabah has \$450 to pay for college textbooks. She expects to pay about \$75 per book. Her friend told her that 4 of them can be checked out of the library for free. Complete the equation below to find the total number of books that

2. ### math

6. Joe played golf with Sam on a speacial par 3 course.. They played nine holes. The expected number of strokes on hole was 3. A birdie is 1 below par. On nine holes Frank made par on 1 hole, got 2 birdies, one eagle, four bogies

3. ### Algebra

Check My answers Please- 1. 3(y + 1) for y = 2 a.6 b.9*** c.7 d.8 2. d + g/h for d = 45, g = 18, and h = 9 a.6*** b.7 c.3 d.4 3.The cost in dollars of a class party is 59 + 13n, where n is the number of people attending. What is

4. ### Math

A biased coin lands heads with probabilty 2/3. The coin is tossed 3 times a) Given that there was at least one head in the three tosses, what is the probability that there were at least two heads? b) use your answer in a) to find

1. ### algebra ll

The number of books checked out from the library varies directly with the number of book reports assigned. There were 3375 books checked out when there were 225 book reports assigned. How many book reports have been assigned if

2. ### math

BOOKS A library contains 2000 books. There are 3 times as many non-fiction books as fiction books. Write and solve a system of equations to determine the number of non-fiction and fiction books.

3. ### Managerial ECON

Suppose that a firm is currently employing 20 workers, the only variable input, at a wage rate of \$60. The average product of labor is 30, the last worker added 12 units to total output, and total fixed cost is \$3,600. a. What is

4. ### English

1. What is the name for the head of an orphanage? 2. What is the name for the head of an nursery school? 3. What is the name for the head of a day-care center? 4. What is the name for the head of a senior center? 5. What is the