a)    Compute s^2

Suppose that you wanted to design an investigation that examined the association between energy drink consumption and social interaction. You select your sample population and begin making your observations. As the research progresses, you suspect that a number of the subjects exhibit behavioral changes simply related to their knowledge of being enrolled in the study and the increased attention they are receiving as subjects. This phenomenon is known as: Group of answer choices selection bias the Hawthorne effect healthy participant effect misclassification error the Rosenthal effect

Are birthdays "evenly distributed" throughout the year, or are they more common during some parts of the year than others? Owners of a children's toy store chain asked this question. Some data collected by the chain are summarized in the table below. The data were obtained from a random sample of 180 people. The birthdate of each person was recorded, and each of these dates was placed into one of four categories: winter (December 21-March 20), spring (March 21-June 20), summer (June 21-September 20), and fall (September 21-December 20). The numbers in the first row of the table are the frequencies observed in the sample for these season categories. The numbers in the second row are the expected frequencies under the assumption that birthdays are equally likely during each season of the year. The bottom row of numbers gives the following value for each of the season categories. (Each expert I have asked has gotten the critical value wrong so I added a picture of the correct formula to…

Travelers who have no intention of showing up often fail to cancel their hotel reservations in a timely manner.  These        travelers are known, in the parlance of the hospitality trade, as “no-shows”.  To protect against no-shows and late        cancellations, hotels invariably overbook rooms.  A recent study examined the problems of over-booking rooms in the hotel        industry.  The following data, extracted from the study represent the daily numbers of late cancellations and no-shows for a        random sample of 10 days at a hotel:     18, 16, 16, 16, 14, 18, 16, 18, 14, 19.   a)    Compute s, the sample s.d. for the data set

A local university boasts that its School of Engineering attracts the top students from around the country. As proof of this claim, they say that the average Math SAT score for their students is higher than the average Math SAT score of 610 at most other Engineering schools. A random sample of Engineering students is taken, and their Math SAT scores are recorded in this data Data: Engineer Business 640 537 709 525 521 552 642 474 646. 575 620 515 534 626 664 550 681 558 652 482 623 630 645 575 549. 541 625 576 621 462 660 521 626 467 610 562 605 600 665. 538 567 669 644 666 705 555 661 651 Questions: a. Perform the appropriate test of hypothesis and paste the session window output below. b. What is the value of the test statistic? c. What is the p-value of the test? d. Estimate the average Math SAT score of this school’s engineering students using a 90% confidence interval.

Are birthdays "evenly distributed" throughout the year, or are they more common during some parts of the year than others? Owners of a children's toy store chain asked this question. Some data collected by the chain are summarized in the table below. The data were obtained from a random sample of 180 people. The birthdate of each person was recorded, and each of these dates was placed into one of four categories: winter (December 21-March 20), spring (March 21-June 20), summer (June 21-September 20), and fall (September 21-December 20). The numbers in the first row of the table are the frequencies observed in the sample for these season categories. The numbers in the second row are the expected frequencies under the assumption that birthdays are equally likely during each season of the year. The bottom row of numbers gives the following value for each of the season categories. (Each expert I have asked has gotten the critical value wrong so I added a picture of the correct formula to…

When an audit must be conducted that involves a tedious examination of a large inventory, the audit may be very costly and time consuming if each item in the inventory must be examined. In such situations, the auditor frequently obtains a random sample of items from the complete inventory and uses the results of an audit of the sampled items to check the validity of the company's financial statement. A large company’s financial statement claims an inventory that averages $600 per item. The following data are the auditor’s assessment of a random sample of 75 items from the company’s inventory. The values resulting from the audit are rounded to the nearest dollar. Estimate the mean value of an item in the inventory using a 95% confidence interval. Is there substantial evidence (a 5 .01) that the mean value of an item in the inventory is less than $600? What is the target population for the above inferences? Would normal distribution–based procedures be appropriate for answering the…

3. Travelers who have no intention of showing up often fail to cancel their hotel reservations in a timely manner. These travelers are known, in the parlance of the hospitality trade, as "no-shows". To protect against no-shows and late cancellations, hotels invariably overbook rooms. A recent study examined the problems of over-booking rooms in the hotel industry. The following data, extracted from the study represent the daily numbers of late cancellations and no-shows for a random sample of 10 days at a hotel: 18, 16, 16, 16, 14, 18, 16, 18, 14, 19. c) Count the number of measurements that actually fall within the interval(-28, +2s) and express the interval count as a percentage of total number of measurements. at least 75% 100% 68% 95%

A real-estate appraiser wants to verify the market value for homes on the east side of the city that are very similar to size and style. The appraiser wants to test the popular belief that the average sales price is $37.80 per square foot for such homes. Suppose that a random sample of six sales were selected. The sampled sales prices per square foot are $35.00, $38.10, $37.20, $29.80, $30.30, and $35.40. Assuming a normal distribution is a good model for sales, test the claim that the mean sales price per square foot differs from $37.80 at the 1% significance level.

Sierra College students enrolled in an online Elementary Statistics course were asked to participate in an anonymous onlne survey. The survey asked the students "Which type of device will you primarily use to access your online course in Canvas?". Of the 152 students who answered this question, 20 responded "a desktop computer", 121 responded "a laptop computer", 6 responded "a smartphone", and 5 responded "a tablet". The Sierra College Mathematics Department believes that less than 5% of students enrolled in an online Elementary Statistics course primarily uses a smartphone to access their online course in Canvas. Use the data collected in the survey to conduct a hypothesis testing procedure to test this belief. What conclusion should be reached according to the results of this hypothesis test?