Fundamentals of Statistics (5th Edition)
5th Edition
ISBN: 9780134508306
Author: Michael Sullivan III
Publisher: PEARSON
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Chapter 11.3, Problem 13AYU
NW Ramp Metering Ramp metering is a traffic engineering idea that requires cars entering a freeway to stop for a certain period of time before joining the traffic flow. The theory is that ramp metering controls the number of cars on the freeway and the number of cars accessing the freeway, resulting in a freer flow of cars, which ultimately results in faster travel times. To test whether ramp metering is effective in reducing travel times, engineers in Minneapolis, Minnesota, conducted an experiment in which a section of freeway had ramp meters installed on the on-ramps. The response variable for the study was speed of the vehicles. A random sample of 15 cars on the highway for a Monday at 6 P.M. with the ramp meters on and a second random sample of 15 cars on a different Monday at 6 P.M. with the meters off resulted in the following speeds (in miles per hour).
- a. Draw side-by-side boxplots of each data set. Does there appear to be a difference in the speeds? Are there any outliers?
- b. Are the ramp meters effective in maintaining a higher speed on the freeway? Use the α = 0.10 level of significance.
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Baby walkers are seats hanging from frames that allow babies to sit upright withtheir legs dangling and feet touching the floor. Walkers have wheels on their legsthat allow the infant to propel the walker around the house long before he or she canwalk or even crawl. Typically, babies use walkers between the ages of 4 months and11 months.Because more walkers have tray table in front that block babies’ view of their feet,child psychologists have begun to questions whether walkers affect infants’cognitive development. One study compared mental skills of a random a=sample fothose who used walkers with a random sample of those who never used walkers.Mental skill scores averaged 113 for 54 babies who used walkers (standard deviationof 12) and 123 for 55 babies who did not use walkers (standard deviation of 15).
(A) Is there evidence that the mean mental skill score of babis who use walkers is different from the mean mental skill score of babies who do not use walkers? Explain your Answer.
In a study on speed control, it was found that the main
reasons for regulations were to make traffic flow more
efficient and to minimize the risk of danger. An area that
was focused on in the study was the distance required
to completely stop a vehicle at various speeds. Use the
following table to answer the questions.
МPH
Braking distance (feet)
20
20
30
45
40
81
50
133
60
205
80
411
Assume MPH is going to be used to predict stopping
distance.
Which of the two variables is the independent
variable?
Which is the dependent variable?
What type of variable is the independent variable?
What type of variable is the independent variable?
Is there a linear relationship between the two
variables?
Is the relationship positive or negative?
:: The dependent variable is miles per hour
:: The independent variable is miles per hour
: The dependent variable is braking distance
: The independent variable is braking distance
:: Miles per hour is a continuous quantitative variable
:: Miles per hour is a…
Chapter 11 Solutions
Fundamentals of Statistics (5th Edition)
Ch. 11.1 - A sampling method is _____ when the individuals...Ch. 11.1 - A sampling method is _____ when the individuals...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - Prob. 8AYUCh. 11.1 - In Problems 912, conduct each test at the = 0.05...Ch. 11.1 - In Problems 912, conduct each test at the = 0.05...
Ch. 11.1 - In Problems 912, conduct each test at the = 0.05...Ch. 11.1 - In Problems 912, conduct each test at the = 0.05...Ch. 11.1 - In Problems 1316, construct a confidence interval...Ch. 11.1 - Prob. 14AYUCh. 11.1 - In Problems 1316, construct a confidence interval...Ch. 11.1 - In Problems 1316, construct a confidence interval...Ch. 11.1 - NW Prevnar The drug Prevnar is a vaccine meant to...Ch. 11.1 - Prevnar Part 2 In randomized, double-blind...Ch. 11.1 - Prob. 19AYUCh. 11.1 - Views on the Death Penalty The Pew Research Group...Ch. 11.1 - NW Tattoos The Harris Poll conducted a survey in...Ch. 11.1 - Body Mass Index The body mass index (BMI) of an...Ch. 11.1 - Public Cell Phone Conversations Researchers at...Ch. 11.1 - Prob. 24AYUCh. 11.1 - Side Effects In clinical trials of the allergy...Ch. 11.1 - Practical versus Statistical Significance In...Ch. 11.1 - Prob. 27AYUCh. 11.1 - Prob. 28AYUCh. 11.1 - Deficit Reduction In the Sullivan Statistics...Ch. 11.1 - Prob. 30AYUCh. 11.1 - Prob. 31AYUCh. 11.1 - Prob. 32AYUCh. 11.1 - Prob. 33AYUCh. 11.1 - Prob. 34AYUCh. 11.1 - Prob. 35AYUCh. 11.1 - Putting It Together: Salk Vaccine On April 12,...Ch. 11.1 - Why do we use a pooled estimate of the population...Ch. 11.1 - Explain the difference between an independent and...Ch. 11.2 - A researcher wants to show the mean from...Ch. 11.2 - A researcher wants to show the mean from...Ch. 11.2 - In Problems 3 and 4, assume that the differences...Ch. 11.2 - a. Determine di = Xi Yi for each pair of data. b....Ch. 11.2 - Naughty or Nice? An experiment was conducted in...Ch. 11.2 - Caffeine-Enhanced Workout? Since its removal from...Ch. 11.2 - NW Muzzle Velocity The following data represent...Ch. 11.2 - Reaction Time In an experiment conducted online at...Ch. 11.2 - Prob. 9AYUCh. 11.2 - Secchi Disk A Secchi disk is an 8-inch-diameter...Ch. 11.2 - Getting Taller? To test the belief that sons are...Ch. 11.2 - Prob. 12AYUCh. 11.2 - Prob. 13AYUCh. 11.2 - Car Rentals The following data represent the daily...Ch. 11.2 - DUI Simulator To illustrate the effects of driving...Ch. 11.2 - Prob. 16AYUCh. 11.2 - Prob. 17AYUCh. 11.2 - Putting It Together: Glide Testing You are a...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - In Problems 16, assume that the populations are...Ch. 11.3 - Elapsed Time to Earn a Bachelors Degree A...Ch. 11.3 - Sugary Beverages It has been reported that...Ch. 11.3 - Prob. 9AYUCh. 11.3 - Walking in the Airport, Part II Do business...Ch. 11.3 - Priming Two Dutch researchers conducted a study in...Ch. 11.3 - Prob. 12AYUCh. 11.3 - NW Ramp Metering Ramp metering is a traffic...Ch. 11.3 - Prob. 14AYUCh. 11.3 - Bacteria in Hospital Carpeting Researchers wanted...Ch. 11.3 - Visual versus Textual Learners Researchers wanted...Ch. 11.3 - Prob. 17AYUCh. 11.3 - Prob. 18AYUCh. 11.3 - Prob. 19AYUCh. 11.3 - Prob. 20AYUCh. 11.3 - Prob. 21AYUCh. 11.3 - Prob. 22AYUCh. 11.3 - Putting It Together: Online Homework Professor...Ch. 11.3 - Prob. 24AYUCh. 11.3 - College Skills The Collegiate Learning Assessment...Ch. 11.3 - MythBusters In a MythBusters episode, the question...Ch. 11.3 - Prob. 27AYUCh. 11.4 - Prob. 1AYUCh. 11.4 - Prob. 2AYUCh. 11.4 - Prob. 3AYUCh. 11.4 - Prob. 4AYUCh. 11.4 - Prob. 5AYUCh. 11.4 - The following data represent the measure of a...Ch. 11.4 - Prob. 7AYUCh. 11.4 - TIMS Report and Kumon TIMS is an acronym for the...Ch. 11.4 - Age Difference in Married Couples What is the...Ch. 11.4 - Prob. 10AYUCh. 11.4 - Prob. 11AYUCh. 11.4 - Prob. 12AYUCh. 11.4 - Prob. 13AYUCh. 11.4 - Prob. 14AYUCh. 11.4 - Prob. 15AYUCh. 11.4 - Extramarital Affairs Is there a difference in the...Ch. 11.4 - Multitasking in School In todays wired society,...Ch. 11.4 - Prob. 18AYUCh. 11.4 - Hospital Readmission As of October 1, 2012,...Ch. 11.4 - Behavior and Gender at Work Researchers wanted to...Ch. 11.4 - Prob. 21AYUCh. 11.4 - Prob. 22AYUCh. 11.4 - Prob. 23AYUCh. 11.4 - Prob. 24AYUCh. 11.4 - Prob. 25AYUCh. 11.4 - Prob. 26AYUCh. 11.4 - Prob. 27AYUCh. 11.4 - In Problems 2231, for each study, explain which...Ch. 11.4 - Prob. 29AYUCh. 11.4 - Prob. 30AYUCh. 11.4 - In Problems 2231, for each study, explain which...Ch. 11 - In Problems 1 and 2, determine if the sampling is...Ch. 11 - In Problems 1 and 2, determine if the sampling is...Ch. 11 - In Problem 3, assume that the paired differences...Ch. 11 - In Problems 4 and 5, assume that the populations...Ch. 11 - In Problems 4 and 5, assume that the populations...Ch. 11 - A random sample of n1 = 555 individuals results in...Ch. 11 - Height versus Arm Span A statistics student heard...Ch. 11 - McDonalds versus Wendys A student wanted to...Ch. 11 - Treatment for Osteoporosis Osteoporosis is a...Ch. 11 - Determining Sample Size A nutritionist wants to...Ch. 11 - Height versus Arm Span Construct and interpret a...Ch. 11 - Prob. 12RECh. 11 - Prob. 1CTCh. 11 - Prob. 2CTCh. 11 - Prob. 3CTCh. 11 - Prob. 4CTCh. 11 - Prob. 5CTCh. 11 - Prob. 6CTCh. 11 - Prob. 7CTCh. 11 - In a study conducted to determine the role that...Ch. 11 - Researchers had a car traveling 10 miles per hour...Ch. 11 - Zoloft is a drug used to treat...Ch. 11 - Does hypnotism result in a different success rate...Ch. 11 - A researcher wants to estimate the difference...Ch. 11 - It is commonplace to gain weight after quitting...Ch. 11 - Dr. Penelope Nicholls is interested in exploring a...Ch. 11 - Dr. Penelope Nicholls is interested in exploring a...
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