MyLab Statistics with Pearson eText -- Standalone Access Card -- for Intro Stats (5th Edition)
5th Edition
ISBN: 9780134768366
Author: Richard D. De Veaux, Paul F. Velleman, David E. Bock
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Question
Chapter 6, Problem 15E
To determine
Comment on the association between the variables using the
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Arterial Cord pH. Umbilical cord blood analysis immediately after delivery is one way to measure the health of an infant after birth. Researchers G. Natalucci et al. used it as a predictor of brain maturation of preterm infants in the article “Functional Brain Maturation Assessed During Early Life Correlates with Anatomical Brain Maturation at Term-Equivalent Age in Preterm Infants” (Pediatric Research, Vol. 74. No. 1, pp. 68–74). Based on this study, we will assume that, for preterm infants, the pH level of the arterial cord (one vessel in the umbilical cord) is normally distributed with mean 7.32 and standard deviation 0.1. Find the percentage of preterm infants who have arterial cord pH levels
a. between 7.0 and 7.5.
b. over 7.4.
Q. The hippocampus shrinks in late adulthood, leading to impaired memory and increased risk for demen- tia. In a study of evaluating whether exercise training expands the hippocampus and improves spatial memory, 60 healthy but sedentary participants, aged 58 to 70, joined a one-year aerobic exercise pro- gram. Magnetic resonance images were collected before the intervention and again after the completion of the program and participants’ hippocampal volumes (in cm3) were measured.
(a) Does exercise training increase the average size of hippocampus by more than 0.1 cm3? Give a test at 5% level of significance.
Body Fat. J. McWhorter et al. of the College of Health Sciences at the University of Nevada, Las Vegas, studied physical therapy students during their graduate-school years. The researchers were interested in the fact that, although graduate physical-therapy students are taught the principles of fitness, some have difficulty finding the time to implement those principles. In the study, published as “An Evaluation of Physical Fitness Parameters for Graduate Students” (Journal of American College Health, Vol. 51, No. 1, pp. 32–37), a sample of 27 female graduate physical-therapy students had a mean of 22.46 percent body fat.
a. Assuming that percent body fat of female graduate physicaltherapy students is normally distributed with standard deviation 4.10 percent body fat, determine a 95% confidence interval for the mean percent body fat of all female graduate physical-therapy students.
b. Obtain the margin of error, E, for the confidence interval you found in part (a).
c. Explain the…
Chapter 6 Solutions
MyLab Statistics with Pearson eText -- Standalone Access Card -- for Intro Stats (5th Edition)
Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Prob. 4JCCh. 6.2 - Prob. 5JCCh. 6 - Association Suppose you were to collect data for...Ch. 6 - Association II Suppose you were to collect data...Ch. 6 - Bookstore sales Consider the following data from a...Ch. 6 - Prob. 4ECh. 6 - Prob. 5E
Ch. 6 - Correlation facts II If we assume that the...Ch. 6 - Prob. 7ECh. 6 - Prob. 8ECh. 6 - Prob. 9ECh. 6 - Prob. 10ECh. 6 - Association III Suppose you were to collect data...Ch. 6 - Association IV Suppose you were to collect data...Ch. 6 - Prob. 13ECh. 6 - Prob. 14ECh. 6 - Prob. 15ECh. 6 - Prob. 16ECh. 6 - Firing pottery A ceramics factory can fire eight...Ch. 6 - Coffee sales Owners of a new coffee shop tracked...Ch. 6 - Matching Here are several scatterplots. The...Ch. 6 - Matching II Here are several scatterplots. The...Ch. 6 - Prob. 21ECh. 6 - Car thefts The National Insurance Crime Bureau...Ch. 6 - Prob. 23ECh. 6 - Antidepressants A study compared the effectiveness...Ch. 6 - Streams and hard water In a study of streams in...Ch. 6 - Traffic headaches A study of traffic delays in 68...Ch. 6 - Cold nights Is there an association between time...Ch. 6 - Association V A researcher investigating the...Ch. 6 - Prob. 29ECh. 6 - Prob. 30ECh. 6 - Correlation errors Your Economics instructor...Ch. 6 - More correlation errors Students in the Economics...Ch. 6 - Height and reading A researcher studies children...Ch. 6 - Prob. 34ECh. 6 - Correlation conclusions I The correlation between...Ch. 6 - Prob. 36ECh. 6 - Prob. 37ECh. 6 - Sample survey A polling organization is checking...Ch. 6 - Income and housing The Office of Federal Housing...Ch. 6 - Interest rates and mortgages 2015 Since 1985,...Ch. 6 - Fuel economy 2016 Here are engine size...Ch. 6 - Drug abuse A survey was conducted in the United...Ch. 6 - Prob. 43ECh. 6 - Burgers again In the previous exercise you...Ch. 6 - Prob. 45ECh. 6 - Second inning 2016 Perhaps fans are just more...Ch. 6 - Prob. 47ECh. 6 - Prob. 48ECh. 6 - Thrills 2013 Since 1994, the Best Roller Coaster...Ch. 6 - Thrills II For the roller coaster data in Exercise...Ch. 6 - Prob. 51ECh. 6 - Vehicle weights The Minnesota Department of...Ch. 6 - Prob. 53ECh. 6 - Flights 2016 Here are the number of domestic...
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
- Research engineers with the University of Kentucky Transportation Research Program have collected data on accidents occurring at all intersections in Lexington, Kentucky, over a period of 5 years. One of the goals to study was to compare the average number of left-turn accidents at locations with and without left turn only lanes to develop numerical warrants (or guidelines) for the installation of left turn lanes. a) Determine the population of the interest, its sample and variables. b) List one suitable method to collect the data.arrow_forwardResearchers are studying pomegranate’s antioxidant properties to see if it might have any beneficial effects in the treatment of cancer. One such study investigated whether pomegranate fruit extract (PFE) was effective in slowing the growth of prostate cancer tumors. In this study, 24 mice were injected with cancer cells, then the mice were randomly assigned to one of three treatment groups. The data on y = average tumor volume (in mm3) and x = number of days after injection of cancer cells for the mice that received plain drinking water is shown in picture below: a. Find (to three decimal places) zy, and zxzy for the pair (23,580): zy = zxzy = b. Compute Pearson’s sample correlation coefficient for the given data to four decimal places. c. Compute the slope, b, for the least-squares regression line to two decimal places d. Use b to calculate a and write the equation for the least-squares regression line a= y= e. Predict the average tumor volume (y) for a mouse 20 days…arrow_forwardAuto noise filters In a statement to a Senate Public WorksCommittee, a senior executive of Texaco, Inc., cited astudy on the effectiveness of auto filters on reducing noise. Because of concerns about performance, two types of fil-ters were studied, a standard silencer and a new device developed by the Associated Octel Company. Here are theboxplots from the data on noise reduction (in decibels) ofthe two filters. Type 1 = standard; Type 2 = Octel. ANOVA Table Source DFSum ofSquaresMeanSquare F-Ratio P-ValueType 1 6.31 6.31 0.7673 0.3874Error 33 271.47 8.22Total 34 2.77Means and Std DeviationsLevel n Mean StdDevStandard 18 81.5556 3.2166Octel 17 80.7059 2.43708a) What are the null and alternative hypotheses?b) What do you conclude from the ANOVA table?c) Do the assumptions for the test seem to be reasonable?d) Perform a two-sample pooled t-test of the difference.What P-value do you get? Show that the square of thet-statistic is the same (to rounding error) as the F-ratio.arrow_forward
- A local coach wants to see if training in light rooms or dark rooms impacts athlete performance. With the single team, the coach tries training in different conditions and takes measurements. With measurements in hand, the coach is ready to analyze in Microsoft Excel. Which test should be selected from the menu? t-Test: Paired Two Sample for Means Descriptive Statistics t-Test: Two-Sample Assuming Equal Variance Fourier Analysisarrow_forwardDetermine the kurtosis if the data given is a sample.arrow_forwardFrom the article “Association of cognitive functioning with retinal nerve fiber layer thickness” by van Koolwijk et al., in Investigative Ophthalmology & Visual Science, October 2009, Vol. 50, No. 10, below is table 2 showing the results of fitting several multiple linear regression models for different response variables. Write down the fitted model corresponding to the last row of the table. You can leave the intercept as hatB0. Interpret the coefficient values corresponding to the RNFL Thickness and Male variables.arrow_forward
- A study is conducted in patients with HIV. The primary outcome is CD4 cell count, which is a measure of the stage of the disease. Lower CD4 counts are associated with more advanced disease. The investigators are interested in the association between vitamin and mineral supplements and CD4 count. A multiple regression analysis is performed relating CD4 count to the use of supplements (coded as 1 = yes and 0 = no) and to the duration of HIV in years (i.e., the number of years between the diagnosis of HIV and the study date). For the analysis, y = CD4 count: = 501.41 + 12.67 Supplements − 30.23 Duration of HIV. What is the expected CD4 count for a patient taking supplements who has had HIV for 2.5 years? What is the expected CD4 count for a patient not taking supplements who was diagnosed with HIV at study enrollment? What is the expected CD4 count for a patient not taking supplements who has had HIV for 2.5 years? If we compare two patients and one has had HIV for 5 years longer…arrow_forwardA physiologist has conducted an experiment to evaluate the effect of hormone X on sexual behavior. Ten rats were injected with hormone X and 10 other rats received a placebo injection. The number of matings was counted over a 20-minute period. The results are shown in the table below. Table 1: Data from hormone X experiment Group 1 Hormone X Group 2 Placebo X1 (X1) 2 X2 (X1) 2 8 64 5 25 10 100 6 36 12 144 3 9 6 36 4 16 6 36 7 49 7 49 8 64 9 81 6 36 8 64 5 25 7 49 4 16 11 121 8 64 84 744 56 340 a) What is the alternative hypothesis? Use a nondirectional hypothesis. b) What is the null hypothesis? c) What do you conclude? Use α = 0.05 (2-tail)arrow_forwardThe provided Excel image shows a dataset consisting of ten Explanatory values stored within the cell range of A2 through A11, and ten corresponding Response values stored within the cell range of B2 through B11. Compute a least-squares linear regression model for this dataset. Using the model: What is the percentage value, of the Coefficient of Determination? Round to two digits past the decimal point, and include a percentage symbol after your answer (with no spaces). ________________________________________ Using the model: What Response value is predicted to result from an Explanatory value of 74? (Round to two digits past the decimal point) __________________________________________ Hint: Coefficient of Determination: Remember this is the value which results when we square the correlation Remember to give your answer in percentage format Remember to include a percentage symbol after your answer (with no spaces) Remember we can tell Excel to show this value directly…arrow_forward
- Researchers1 asked parents of 19 American children, ages 8 to 12, to complete surveys on the number of hours their children spent reading and on the number of hours they spent on screen-based media time. Each of the children also underwent magnetic resonance imaging to assess connectivity in the brain. More time spent reading was associated with higher connectivity,while more screen time was associated with lower connectivity in the brains of the children.1. Horowitz-Kraus T and Hutton J, “Brain connectivity in children is increased by the time they spend reading books and decreased by the length of exposure to screen-based media,” How many variables are there?arrow_forward4. A study is conducted in patients with HIV. The primary outcome is CD4 cell count, which is a measure of the stage of the disease. Lower CD4 counts are associated with more advanced disease. The investigators are interested in the association between vitamin and mineral supplements and CD4 count. A multiple regression analysis is performed relating CD4 count to use of supplements (coded as 1 = yes, 0 = no) and to duration of HIV, in years (i.e., the number of years between the diagnosis of HIV and the study date). For the analysis, = CD4 count. = 501.41 + 12.67 Supplements – 30.23 Duration of HIV What is the expected CD4 count for a patient not taking supplements who has had HIV for 5 years? A) 350.26 B) 501.41 C) 30.23 D) 5arrow_forwardLow-Birth-Weight Hospital Stays. Data on low-birthweight babies were collected over a 2-year period by 14 participating centers of the National Institute of Child Health and Human Development Neonatal Research Network. Results were reported by J. Lemons et al. in the on-line paper “Very Low Birth Weight Outcomes of the National Institute of ChildHealth and Human Development Neonatal Research Network” (Pediatrics, Vol. 107, No. 1, p. e1). For the 1084 surviving babies whose birth weights were 751– 1000 grams, the average length of stay in the hospital was 86 days, although one center had an average of 66 days and another had an average of 108 days. a. Can the mean lengths of stay be considered population means? Explain your answer.b. Assuming that the population standard deviation is 12 days, determine the z-score for a baby’s length of stay of 86 days at the center where the mean was 66 days.c. Assuming that the population standard deviation is 12 days, determine the z-score for a…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:CengageGlencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillElementary Linear Algebra (MindTap Course List)AlgebraISBN:9781305658004Author:Ron LarsonPublisher:Cengage Learning
- Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Elementary Linear Algebra (MindTap Course List)
Algebra
ISBN:9781305658004
Author:Ron Larson
Publisher:Cengage Learning
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