Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Textbook Question
Chapter 2.3, Problem 56E
In each of Exercises 2.54–2.59, we have presented a “data scenario.” In each case, decide which type of grouping (single-value, limit, or cutpoint) is probably the best.
2.56 Sleep Aids. The additional sleep, to the nearest tenth of an hour, obtained by a sample of 100 patients by using a particular brand of sleeping pill
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Heart rate during laughter. Laughter is often called “the best medicine,” since studies have shown that laughter can reduce muscle tension and increase oxygenation of the blood. In the International Journal of Obesity (Jan. 2007), researchers at Vanderbilt University investigated the physiological changes that accompany laughter. Ninety subjects (18–34 years old) watched film clips designed to evoke laughter. During the laughing period, the researchers measured the heart rate (beats per minute) of each subject,
with the following summary results:
Mean = 73.5,
Standard Deviation = 6. n=90 (we can treat this as a large sample and use z)
It is well known that the mean resting heart rate of adults is 71 beats per minute. Based on the research on laughter and heart rate, we would expect subjects to have a higher heart beat rate while laughing.Construct 95% Confidence interval using z value. What is the lower bound of CI?
a) Calculate the value of the test statistic.(z*)
b) If…
A team of pharmacists was researching two sleeping pills they were developing. 20
individuals took part in the study and they were randomly divided into two groups and one
group received sleeping pills 1 and the other group sleeping pills 2. The pharmacists then
measured how long the individuals slept after ingestion. The data can be seen below:
SLEEPING MEDICINE 1
SLEEPING MEDICINE 2
9.2
6.8
7.4
6.2
10.1
8.1
6.8
7.2
9.1
5.8
8.2
8.8
9.2
6.2
8.8
7.1
7.6
7.3
8.8
6.9
Let us now assume that the assumptions that need to apply can be used in a study such as this
to confirm the efficacy of the drugs. Examine with an appropriate hypothesis test whether
there is a difference in mean sleep duration after taking the two drugs. In the event that you
need to check whether the distribution in the two groups can be assumed to be the same, it is
sufficient to use the rule of thumb to determine this. Sleep duration can be assumed to follow
a normal distribution. Use a = 0.05. Show all six steps.
Please…
Chapter 2 Solutions
Introductory Statistics (10th Edition)
Ch. 2.1 - Give an example, other than those presented in...Ch. 2.1 - Explain the meaning of a. qualitative variable. b....Ch. 2.1 - Explain the meaning of a. qualitative data. b....Ch. 2.1 - Provide a reason why the classification of data is...Ch. 2.1 - Of the variables you have studied so far, which...Ch. 2.1 - For each part of Exercises 2.62.11, classify the...Ch. 2.1 - Earthquakes. The U.S. Geological Survey monitors...Ch. 2.1 - Top 10 IPOs. An online article from the Washington...Ch. 2.1 - Earnings from the Crypt. On the Celebrity NetWorth...Ch. 2.1 - World University Rankings. The Times Higher...
Ch. 2.1 - Recording Industry Statistics. The Recording...Ch. 2.1 - RBI Kings. As reported on MLB.com, the five...Ch. 2.1 - Top Broadcast Shows. As reported in Primetime...Ch. 2.1 - The Fulbright Program. The U.S. governments...Ch. 2.1 - Top 10 Green Cars. The following table presents...Ch. 2.1 - Ordinal Data. Another important type of data is...Ch. 2.2 - What is a frequency distribution of qualitative...Ch. 2.2 - Explain the difference between a. frequency and...Ch. 2.2 - Answer true or false to each of the statements in...Ch. 2.2 - In Exercises 2.202.25, we have presented some...Ch. 2.2 - Prob. 21ECh. 2.2 - In Exercises 2.202.25, we have presented some...Ch. 2.2 - Prob. 23ECh. 2.2 - In Exercises 2.202.25, we have presented some...Ch. 2.2 - In Exercises 2.202.25, we have presented some...Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - For each data set in Exercises 2.262.31, a....Ch. 2.2 - In each of Exercises 2.322.37, we have presented a...Ch. 2.2 - In each of Exercises 2.322.37, we have presented a...Ch. 2.2 - In each of Exercises 2.322.37, we have presented a...Ch. 2.2 - In each of Exercises 2.322.37, we have presented a...Ch. 2.2 - In each of Exercises 2.322.37, we have presented a...Ch. 2.2 - Prob. 37ECh. 2.2 - Health Status. The National Center for Health...Ch. 2.2 - In Exercises 2.392.41, use the technology of your...Ch. 2.2 - Prob. 40ECh. 2.2 - In Exercises 2.392.41, use the technology of your...Ch. 2.3 - Identify an important reason for grouping data.Ch. 2.3 - Do the concepts of class limits, marks, cutpoints,...Ch. 2.3 - State three of the most important guidelines in...Ch. 2.3 - With regard to grouping quantitative data into...Ch. 2.3 - For quantitative data, we examined three types of...Ch. 2.3 - We used slightly different methods for determining...Ch. 2.3 - Explain the difference between a frequency...Ch. 2.3 - Explain the advantages and disadvantages of...Ch. 2.3 - For data that are grouped in classes based on more...Ch. 2.3 - Discuss the relative advantages and disadvantages...Ch. 2.3 - Suppose that you have a data set that contains a...Ch. 2.3 - Suppose that you have constructed a stem-and-leaf...Ch. 2.3 - In each of Exercises 2.542.59, we have presented a...Ch. 2.3 - In each of Exercises 2.542.59, we have presented a...Ch. 2.3 - In each of Exercises 2.542.59, we have presented a...Ch. 2.3 - In each of Exercises 2.542.59, we have presented a...Ch. 2.3 - Prob. 58ECh. 2.3 - In each of Exercises 2.542.59, we have presented a...Ch. 2.3 - Prob. 60ECh. 2.3 - Prob. 61ECh. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - Prob. 66ECh. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - Prob. 69ECh. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - In Exercises 2.602.71, we have presented some...Ch. 2.3 - Prob. 72ECh. 2.3 - In each of Exercises 2.722.75, construct a dotplot...Ch. 2.3 - Prob. 74ECh. 2.3 - In each of Exercises 2.722.75, construct a dotplot...Ch. 2.3 - In each of Exercises 2.762.79, construct a...Ch. 2.3 - Prob. 77ECh. 2.3 - In each of Exercises 2.762.79, construct a...Ch. 2.3 - Prob. 79ECh. 2.3 - Prob. 80ECh. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - For each data set in Exercises 2.802.91, use the...Ch. 2.3 - Prob. 87ECh. 2.3 - Prob. 88ECh. 2.3 - Prob. 89ECh. 2.3 - Prob. 90ECh. 2.3 - Prob. 91ECh. 2.3 - Prob. 92ECh. 2.3 - Age of Passenger Cars. According to R. L. Polk ...Ch. 2.3 - Stressed-Out Bus Drivers. Frustrated passengers,...Ch. 2.3 - Acute Postoperative Days. Several neurosurgeons...Ch. 2.3 - MMs. In the article Sweetening StatisticsWhat MMs...Ch. 2.3 - Women in the Workforce. In an issue of Science...Ch. 2.3 - Process Capability. R. Morris and E. Watson...Ch. 2.3 - University Patents. The number of patents a...Ch. 2.3 - Prob. 100ECh. 2.3 - Prob. 101ECh. 2.3 - Adjusted Gross Incomes. The Internal Revenue...Ch. 2.3 - Cholesterol Levels. According to the National...Ch. 2.3 - Hospital Beds. The number of hospital beds...Ch. 2.3 - Parkinsons Disease. Parkinsons disease affects...Ch. 2.3 - The Great White Shark. In an article titled Great...Ch. 2.3 - The Beatles. In the article, Length of The Beatles...Ch. 2.3 - High School Completion. As reported by the U.S....Ch. 2.3 - Prob. 109ECh. 2.3 - Body Temperature. A study by researchers at the...Ch. 2.3 - Exam Scores. The exam scores for the students in...Ch. 2.3 - Prob. 112ECh. 2.3 - Prob. 113ECh. 2.3 - Age and Gender. The following bivariate data on...Ch. 2.3 - Prob. 115ECh. 2.3 - Clocking the Cheetah. Construct a...Ch. 2.3 - Prob. 117ECh. 2.3 - Residential Energy Consumption. Refer to the...Ch. 2.3 - Prob. 119ECh. 2.3 - Cardiovascular Hospitalizations. The Florida State...Ch. 2.3 - Prob. 121ECh. 2.4 - In each of Exercises 2.1222.127, explain the...Ch. 2.4 - In each of Exercises 2.1222.127, explain the...Ch. 2.4 - In each of Exercises 2.1222.127, explain the...Ch. 2.4 - Prob. 125ECh. 2.4 - Prob. 126ECh. 2.4 - Prob. 127ECh. 2.4 - Prob. 128ECh. 2.4 - Suppose that a variable of a population has a...Ch. 2.4 - Prob. 130ECh. 2.4 - Identify and sketch three distribution shapes that...Ch. 2.4 - Prob. 132ECh. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - In each of Exercises 2.1322.139, we have drawn a...Ch. 2.4 - Prob. 139ECh. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - Prob. 142ECh. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - In each of Exercises 2.1402.149, we have provided...Ch. 2.4 - Prob. 147ECh. 2.4 - Prob. 148ECh. 2.4 - Prob. 149ECh. 2.4 - Old Faithful. Old Faithful is a geyser in...Ch. 2.4 - SnowGoose Nests. In the article Trophic...Ch. 2.4 - Prob. 152ECh. 2.4 - In each of Exercises 2.1522.157, a. use the...Ch. 2.4 - In each of Exercises 2.1522.157, a. use the...Ch. 2.4 - Prob. 155ECh. 2.4 - In each of Exercises 2.1522.157, a. use the...Ch. 2.4 - In each of Exercises 2.1522.157, a. use the...Ch. 2.4 - Standard Normal Distribution. One of the most...Ch. 2.5 - Give one reason why constructing and reading...Ch. 2.5 - Prob. 163ECh. 2.5 - Reading Skills. Each year the director of the...Ch. 2.5 - Americas Melting Pot. The U.S. Census Bureau...Ch. 2.5 - Prob. 167ECh. 2.5 - Drunk-Driving Fatalities. Drunk-driving fatalities...Ch. 2.5 - Prob. 169ECh. 2.5 - Prob. 170ECh. 2.5 - Prob. 171ECh. 2 - This problem is about variables. a. What is a...Ch. 2 - This problem is about data. a. What are data? b....Ch. 2 - For a qualitative data set, what is a a. frequency...Ch. 2 - What is the relationship between a frequency or...Ch. 2 - Identify two main types of graphical displays that...Ch. 2 - In a bar chart, unlike in a histogram, the bars do...Ch. 2 - Some users of statistics prefer pie charts to bar...Ch. 2 - When is the use of single-value grouping...Ch. 2 - A quantitative data set has been grouped by using...Ch. 2 - A quantitative data set has been grouped by using...Ch. 2 - A quantitative data set has been grouped by using...Ch. 2 - A quantitative data set has been grouped by using...Ch. 2 - Explain the relative positioning of the bars in a...Ch. 2 - Sketch the curve corresponding to each of the...Ch. 2 - Draw a smooth curve that represents a symmetric...Ch. 2 - Prob. 16RPCh. 2 - Largest Hydroelectric Plants. According to...Ch. 2 - DVD Players. Refer to Example 2.16 on page 60. a....Ch. 2 - Inauguration Ages. From the Information Please...Ch. 2 - Inauguration Ages. Refer to Problem 19. Construct...Ch. 2 - Prob. 21RPCh. 2 - Prob. 22RPCh. 2 - Busy Bank Tellers. The Prescott National Bank has...Ch. 2 - On-Time Arrivals. The Air Travel Consumer Report...Ch. 2 - Old Ballplayers. From the ESPN Web site, we...Ch. 2 - Prob. 26RPCh. 2 - U.S. Divisions. The U.S. Census Bureau divides the...Ch. 2 - Prob. 28RPCh. 2 - Prob. 29RPCh. 2 - Hair and Eye Color. In the article Graphical...Ch. 2 - Prob. 31RPCh. 2 - In Problems 3133, a. identify the population and...Ch. 2 - In Problems 3133, a. identify the population and...Ch. 2 - UWEC UNDERGRADUATES Recall from Chapter 1 (see...Ch. 2 - Recall that, each year, Forbes magazine publishes...
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