Connect hosted by ALEKS for Elementary Statistics: A Step By Step Approach
10th Edition
ISBN: 9781260041774
Author: Allan Bluman
Publisher: Mcgraw-hill Higher Education (us)
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 7.4, Problem 1AC
Ages of Presidents at the Time of Their Deaths
Shown are the ages (in years) of the Presidents at the times of their deaths.
1. Do the data represent a population or a sample?
2. Select a random sample of 12 ages and find the variance and standard deviation.
3. Find the 95% confidence interval of the standard deviation.
4. Find the standard deviation of all the data values.
5. Does the confidence interval calculated in question 3 contain the standard deviation?
6. If it does not, give a reason why.
7. What assumption(s) must be considered for constructing the confidence interval in step 3?
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
55
5.5
A glass bottle manufacturing company has recorded data on the average
number of defects per 10,000 bottles due to stones (small pieces of rock
embedded in the bottle wall) and the number of weeks since the last furnace
overhaul. The data are shown below.
Defects per 10,000
Weeks
13.0
4
16.1
5
14.5
6
17.8
7
22.0
8
27.4
9
16.8
10
65.6
☐☐
Defects per 10,000
Weeks
34.2
11
12
49.2
13
66.2
81.2
87.4
14
15
16
114.5
17
a. Fit a straight-line regression model to the data and perform the standard
tests for model adequacy.
b. Suggest an appropriate transformation to eliminate the problems encoun-
tered in part a. Fit the transformed model and check for adequacy.
One estimate of the proportion of children with autism in the United States is 1 in 100 (Source: http://www.cbsnews.com/stories/2009/10/05/health/main5363192.shtml). Suppose you are interested in the rate of autism among current school-aged children in Utah. You collect a sample of 400 children between the ages of 5 and 18 and find that three have had a previous diagnosis of an autism disorder. You plan to calculate a 95% confidence interval estimator of the proportion of school-aged children in Utah who have ever had a diagnosis of an autism disorder.
Which of the following is the most likely reason you would use a Wilson estimator to calculate the confidence interval estimator?
It is uncomfortable to define having been diagnosed with autism as a success.
It is possible that if even the actual proportion in Utah is 1%, your sample may only have very few children who have had a previous diagnosis of an autism disorder.
It is an easier way to calculate the confidence…
Problem 2-6. Need help on why its 1.22
Chapter 7 Solutions
Connect hosted by ALEKS for Elementary Statistics: A Step By Step Approach
Ch. 7.1 - What is the difference between a point estimate...Ch. 7.1 - What information is necessary to calculate a...Ch. 7.1 - What is the margin of error?Ch. 7.1 - What is meant by the 95% confidence interval of...Ch. 7.1 - What are three properties of a good estimator?Ch. 7.1 - What statistic best estimates ?Ch. 7.1 - Find each. a. z/2 for the 99% confidence interval...Ch. 7.1 - What is necessary to determine the sample size?Ch. 7.1 - Fuel Efficiency of Cars and Trucks Since 1975 the...Ch. 7.1 - Fast-Food Bills for Drive-Thru Customers A random...
Ch. 7.1 - Overweight Men For a random sample of 60...Ch. 7.1 - Number of Jobs A sociologist found that in a...Ch. 7.1 - Number of Faculty The numbers of faculty at 32...Ch. 7.1 - Freshmen GPAs First-semester GPAs for a random...Ch. 7.1 - Carbohydrate Grams in Commercial Subs The number...Ch. 7.1 - Number of Farms A random sample of the number of...Ch. 7.1 - Gasoline Use A random sample of 36 drivers used on...Ch. 7.1 - Day Care Tuition A random sample of 50...Ch. 7.1 - Hospital Noise Levels Noise levels at various area...Ch. 7.1 - Length of Growing Seasons The growing seasons for...Ch. 7.1 - Christmas Presents How large a sample is needed to...Ch. 7.1 - Hospital Noise Levels In the hospital study cited...Ch. 7.1 - Internet Viewing A researcher wishes to estimate...Ch. 7.1 - Cost of Pizzas A pizza shop owner wishes to find...Ch. 7.1 - Water Temperature If the variance of the water...Ch. 7.1 - Undergraduate GPAs It is desired to estimate the...Ch. 7.2 - Sport Drink Decision Assume you get a new job as a...Ch. 7.2 - What are the properties of the t distribution?Ch. 7.2 - What is meant by degrees of freedom?Ch. 7.2 - Find the values for each. a. t/2 and n = 18 for...Ch. 7.2 - When should the t distribution be used to find a...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - For Exercises 5 through 20, assume that all...Ch. 7.2 - Parking Meter Revenue A one-sided confidence...Ch. 7.3 - Contracting Influenza To answer the questions, use...Ch. 7.3 - In each case, find p and q. a. n = 80 and X = 40...Ch. 7.3 - Find p and q for each situation. a. n = 60 and X =...Ch. 7.3 - Cyber Monday Shopping A survey of 1000 U.S. adults...Ch. 7.3 - Manual Transmission Automobiles In 2014, six...Ch. 7.3 - Holiday Gifts A survey of 100 Americans found that...Ch. 7.3 - Belief in Haunted Places A random sample of 205...Ch. 7.3 - Work Interruptions Research by Steelcase found the...Ch. 7.3 - Travel to Outer Space A CBS News/New York Times...Ch. 7.3 - High School Graduates Who Take the SAT The...Ch. 7.3 - Educational Television In a random sample of 200...Ch. 7.3 - Wi-Fi Access A survey of 50 students in grades 4...Ch. 7.3 - Students Who Major in Business It has been...Ch. 7.3 - Smartphone Ownership A recent survey of 349 people...Ch. 7.3 - Home Internet Access According to a study, 96% of...Ch. 7.3 - Overseas Travel A researcher wishes to be 95%...Ch. 7.3 - Widows A recent study indicated that 29% of the...Ch. 7.3 - Direct Satellite Television It is believed that...Ch. 7.3 - Obesity Obesity is defined as a body mass index...Ch. 7.3 - U.S. Fitness Guidelines According to the World...Ch. 7.3 - Diet Habits A federal report indicated that 27% of...Ch. 7.3 - Gun Control If a random sample of 600 people is...Ch. 7.3 - Survey on Politics In a study, 68% of 1015...Ch. 7.4 - Ages of Presidents at the Time of Their Deaths...Ch. 7.4 - What distribution must be used when computing...Ch. 7.4 - What assumption must be made when computing...Ch. 7.4 - Using Table G, find the values for 2 left and 2...Ch. 7.4 - Lifetimes of Wristwatches Find the 90% confidence...Ch. 7.4 - Carbohydrates in Yogurt The number of...Ch. 7.4 - Carbon Monoxide Deaths A study of...Ch. 7.4 - Pacemaker Batteries A manufacturer of pacemakers...Ch. 7.4 - Age of College Students Find the 90% confidence...Ch. 7.4 - Prob. 9ECh. 7.4 - Stock Prices A random sample of stock prices per...Ch. 7.4 - Cost of an Operation A medical researcher surveyed...Ch. 7.4 - Home Ownership Rates The percentage rates of home...Ch. 7.4 - Calories in a Standard Size Candy Bar Estimate the...Ch. 7.4 - SAT Scores Estimate the variance in mean...Ch. 7.4 - Daily Cholesterol Intake The American Heart...Ch. 7.4 - Calculator Battery Lifetimes A confidence interval...Ch. 7 - Eye Blinks A survey of 49 individuals found that...Ch. 7 - Vacation Days A U.S. Travel Data Center survey...Ch. 7 - Blood Pressure A researcher wishes to estimate...Ch. 7 - Shopping Survey A random sample of 49 shoppers...Ch. 7 - Lengths of Childrens Animated Films The lengths...Ch. 7 - Dog Bites to Postal Workers For a certain urban...Ch. 7 - Number of Credit Cards In a recent survey of 1000...Ch. 7 - Vacation Sites A U.S. Travel Data Centers survey...Ch. 7 - Prob. 7.3.9RECh. 7 - Adult Educational Activities A local county has a...Ch. 7 - Prob. 7.3.11RECh. 7 - Child Care Programs A study found that 73% of...Ch. 7 - Baseball Diameters The standard deviation of the...Ch. 7 - Cost of an Operation A medical researcher surveyed...Ch. 7 - Lifetimes of Snowmobiles A random sample of 15...Ch. 7 - Length of Childrens Animated Films Use the data...Ch. 7 - From the Data Bank choose a variable, find the...Ch. 7 - Repeat Exercise 1, using a different variable and...Ch. 7 - Repeat Exercise 1, using a proportion. For...Ch. 7 - From Data Set III in Appendix B, select a sample...Ch. 7 - From Data Set VI in Appendix B, select a sample of...Ch. 7 - Select a random sample of 20 of the record high...Ch. 7 - Determine whether each statement is true or false....Ch. 7 - Determine whether each statement is true or false....Ch. 7 - Determine whether each statement is true or false....Ch. 7 - Determine whether each statement is true or false....Ch. 7 - When a 99% confidence interval is calculated...Ch. 7 - The best point estimate of the population mean is...Ch. 7 - When the population standard deviation is unknown...Ch. 7 - Complete the following statements with the best...Ch. 7 - Complete the following statements with the best...Ch. 7 - Complete the following statements with the best...Ch. 7 - Complete the following statements with the best...Ch. 7 - Cost of Texts An irate student complained that the...Ch. 7 - Doctor Visit Costs An irate patient complained...Ch. 7 - Weights of Minivans The average weight of 40...Ch. 7 - Ages of Insurance Representatives In a study of 10...Ch. 7 - Prob. 16CQCh. 7 - Burglaries For a certain urban area, it was found...Ch. 7 - Hours Spent Studying A university dean wishes to...Ch. 7 - Prob. 19CQCh. 7 - Prob. 20CQCh. 7 - Prob. 21CQCh. 7 - Prob. 22CQCh. 7 - Prob. 23CQCh. 7 - Prob. 24CQCh. 7 - Prob. 25CQCh. 7 - Prob. 26CQCh. 7 - Critical Thinking Challenges A confidence interval...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- Scenario: As a data analyst for a retail company, you are tasked with examining the relationship between televisions screen size, and prices. Your analysis will involve both correlation and regression methods to quantify and interpret this relationship Make a Scatterplot of screen size vs. price. Explain in one sentence, does there appear to be a positive or a negative correlation between price and screen size? Paste a snapshot of the plot here. Please do not copy paste. Question 1: What is the value of correlation coefficient between screen size and price? Discuss the direction of the relationship (positive, negative, or zero relationship). Also discuss the strength of the relationship Estimate the relationship between screen size and price using a simple linear regression model and interpret the estimated coefficients. In your interpretation, tell the dollar amount by which price will change for each unit of increase in screen size. (The answer for the second part of this…arrow_forwardvery time you conduct a hypothesis test, there are four possible outcomes of your decision to reject or not reject the null hypothesis: (1) You don’t reject the null hypothesis when it is true, (2) you reject the null hypothesis when it is true, (3) you don’t reject the null hypothesis when it is false, and (4) you reject the null hypothesis when it is false. Consider the following analogy: You are an airport security screener. For every passenger who passes through your security checkpoint, you must decide whether to select the passenger for further screening based on your assessment of whether he or she is carrying a weapon. Suppose your null hypothesis is that the passenger has a weapon. As in hypothesis testing, there are four possible outcomes of your decision: (1) You select the passenger for further inspection when the passenger has a weapon, (2) you allow the passenger to board her flight when the passenger has a weapon, (3) you select the passenger for further inspection when…arrow_forwardEKS C ALEKS - Kim Johnson - Ch 6S × 4 www-awy.aleks.com alekscgi/x/sl.exe/16_u-lgNs/kr7j8FB)--BjuvZG weRMign 4tCy83MpSgONH0-ovaPm-Zym e Chrome isn't your default browser Set as default Ch 6 Sec 4 Homework Question 4 of 4 (1 point) | Question Attempt: 2 of Unlimited ✓ 2 ✓ 3 = 4 Stress at work: In a poll conducted by the General Social Survey, 81% of respondents said that their jobs were sometimes or always stressful. Two hundred workers are chosen at random. Use the TI-84 Plus calculator as needed. Round your answer to at least four decimal places. (a) Approximate the probability that 155 or fewer workers find their jobs stressful. (b) Approximate the probability that more than 145 workers find their jobs stressful. (c) Approximate the probability that the number of workers who find their jobs stressful is between 154 and 172 inclusive. Part 1 of 3 The probability that 155 or fewer workers find their jobs stressful is 0.1207 Part 2 of 3 bility that more than 145 workers find their jobs…arrow_forward
- A case-control (or retrospective) study was conducted to investigate a relationship between the colors of helmets worn by motorcycle drivers and whether they are injured or killed in a crash. Results are given in the accompanying table. Using a 0.01 significance level, test the claim that injuries are independent of helmet color. Color of Helmet Black White Yellow Red Blue Controls (not injured) 499 373 32 159 79 Cases (injured 221 108 8 66 38 or killed) Click here to view the chi-square distribution table. Chi-square distribution table Area to the Right of the Critical Value Degrees of Freedom 0.995 0.99 0.975 0.95 0.90 0.10 0.05 0.025 0.01 0.005 C. Ho: Injuries and neimet color are dependent H₁: Injuries and helmet color are independent D. Ho: Whether a crash occurs and helmet color are dependent 1 0.001 0.004 0.016 2.706 3.841 5.024 6.635 7.879 2 0.010 0.020 0.051 0.103 0.211 4.605 5.991 7.378 9.210 10.597 3 0.072 0.115 0.216 0.352 0.584 6.251 7.815 9.348 11.345 12.838 4 0.207 0.297…arrow_forwardConduct the hypothesis test and provide the test statistic and the critical value, and state the conclusion. A person drilled a hole in a die and filled it with a lead weight, then proceeded to roll it 200 times. Here are the observed frequencies for the outcomes of 1, 2, 3, 4, 5, and 6, respectively: 28, 32, 46, 39, 29, 26. Use a 0.025 significance level to test the claim that the outcomes are not equally likely. Does it appear that the loaded die behaves differently than a fair die? Click here to view the chi-square distribution table. The test statistic is (Round to three decimal places as needed.) Chi-square distribution table Area to the Right of the Critical Value Degrees of Freedom 0.995 0.99 0.975 0.95 0.90 0.10 0.05 0.025 0.01 0.005 1 0.001 0.004 0.016 2.706 3.841 5.024 6.635 2 0.010 0.020 0.051 0.103 0.211 4.605 5.991 7.378 9.210 7.879 10.597 3 0.072 0.115 0.216 0.352 0.584 6.251 7.815 9.348 11.345 12.838 4 0.207 0.297 0.484 0.711 1.064 7.779 9.488 11.143 13.277 14.860 5…arrow_forwardThe online clothing retailer e-Parel is conducting a study to estimate the average size of the orders placed by visitors to its website. The project manager desires a $60 bound on the error of estimation at 90% confidence. The population standard deviation is unknown, and a “best guess” of $175 is used as the planning value for σ. Use the Distributions tool to help you answer the questions that follow. 0123 Select a Distribution The z-value for a 90% confidence interval of the population mean is . In order to satisfy the requirement of a $60 bound on the error of estimation, a sample size no smaller than is needed.arrow_forward
- A local electronics store just received a shipment of 620 HDMI cables. The manager wants to estimate the number of defective HDMI cables in the shipment. Rather than checking every HDMI cable, the manager plans to take a simple random sample of size 62 in order to estimate the proportion of defective HDMI cables in the shipment. If the sample proportion of defective HDMI cables, p̂p̂, is greater than 0.0323 (there are more than two defective HDMI cables in the sample), the manager will file a complaint and request a new shipment. Suppose that the true proportion of defective HDMI cables in the shipment is approximately p = 0.02. What is the expected value of the sample proportion? E(Pˆ)E(P^)= Since the sample is to be drawn from a finite population, and since the sample is 5% of the population size, the finite population correction factor needed when you calculate the standard deviation of the sampling distribution. What is the standard deviation of the…arrow_forwardAn automobile battery manufacturer offers a 39/50 warranty on its batteries. The first number in the warranty code is the free-replacement period; the second number is the prorated-credit period. Under this warranty, if a battery fails within 39 months of purchase, the manufacturer replaces the battery at no charge to the consumer. If the battery fails after 39 months but within 50 months, the manufacturer provides a prorated credit toward the purchase of a new battery. The manufacturer assumes that X, the lifetime of its auto batteries, is normally distributed with a mean of 44 months and a standard deviation of 3.6 months. Use the following Distributions tool to help you answer the questions that follow. (Hint: When you adjust the parameters of a distribution, you must reposition the vertical line (or lines) for the correct areas to be displayed.) 0123 Select a Distribution If the manufacturer’s assumptions are correct, it would need to replace of its…arrow_forwardIn regards to conducting a linear contrast after a one-way ANOVA, can you explain how seemingly arbitrary weights that "emphasize or de-emphasize" certain variables in a linear combination and sum to zero are able to provide information about how certain groups differ from each other? For example, if we havethree groups A, B, and C, and we want tocompare the mean of group A with theaverage of groups B and C, the weights inthis case are 1 for group A, and -0.5 for groupsB and C, which sum to zero. But how do these numbers model the relationship of comparing one group to the average of the other two? Does it have to do with how the math is carried out, such as how the test statistic is created?arrow_forward
- Can you simply and intuitively explain the purpose of a contrast to the treatment sum of squares? For example, do orthogonal contrasts partition the treatment sum of squares into additive components that represent the variation due to each contrast? If so, what would be the purpose of this?arrow_forwardThe height of the graph of the probability density function f(x) varies with X as follows (round to four decimal places): X 16 Height of the Graph of the Probability Density Function You are flying out of Terminal 3 at JFK on a Wednesday afternoon between 3:00 and 4:00 PM. You get stuck in a traffic jam on the way to the airport, and if it takes you longer than 12 minutes to clear security, you'll miss your flight. The probability that you'll miss your flight is You have arrived at the airport and have been waiting 10 minutes at the security checkpoint. Recall that if you spend more than 12 minutes clearing security, you will miss your flight. Now what is the probability that you'll miss your flight? ○ 0.5 O 0.25 ○ 0.8333 ○ 0.6667arrow_forwardonsider a random variable x that follows a uniform distribution, with a = 2 and b = 9. What is the probability that x is less than 6? P(x < 6) = 0.2857 P(x < 6) = 0.5714 P(x < 6) = 0.17142 P(x < 6) = 0.4286 What is the probability that x is between 4 and 6? P(4 ≤ x ≤ 6) = 0.2857 P(4 ≤ x ≤ 6) = 0.157135 P(4 ≤ x ≤ 6) = 0.0928525 P(4 ≤ x ≤ 6) = 0.11428arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt
Hypothesis Testing using Confidence Interval Approach; Author: BUM2413 Applied Statistics UMP;https://www.youtube.com/watch?v=Hq1l3e9pLyY;License: Standard YouTube License, CC-BY
Hypothesis Testing - Difference of Two Means - Student's -Distribution & Normal Distribution; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=UcZwyzwWU7o;License: Standard Youtube License