Answer Problem 6.52 for 1 lb rather than 0.5 lb? Obstetrics Figure 6.4b (p. 172) plotted the sampling distribution of the mean from 200 samples of size 5 from the population of 1000 birth-weights...
An article in the Journal of American College Health reports that, in a survey of 1845 college students from a large, southeastern public university, 27% were at risk for at least one sleep disorder,...
Restaurants sometimes provide customer reaction cards so that customers can evaluate their dining experience at the establishment. What kinds of decisions might be made on the basis of this...
Suppose (x - 0 ) / (s/n) = -1.52 and a one- sample t test is performed based on seven subjects. What is thaw two-tailed p-values? Renal Disease The mean serum-creatinine level measured in 12...
What is the coefficient of determination and what does it tell us about the relationship between two variables?
What is the p-value for the test conducted in Problem 7.36? Nutrition Iron-deficiency anemia is an important nutritional health problem in the United States. A dietary assessment was performed on 51...
If the expected difference is 0.10 ln units, then what is the power of such a study if a two-sided test is to be used with = .05? Diabetes Plasma-glucose levels are used to determine the presence of...
What test can be used to assess if there is a change in mean LVM over 4 years? Cardiovascular Disease, Pediatrics Left ventricular mass (LVM) is an important risk factor for subsequent cardiovascular...
Carry out the test procedure mentioned in Problem 8.28, and report a p-value? Ophthalmology A camera has been developed to detect the presence of cataract more accurately. Using this camera, the gray...
What are the appropriate null and alternative hypotheses to compare the means of the two groups? Pulmonary Disease A possible important environmental determinant of lung function in children is the...
Provide a 95% CI for the true mean difference in FEV between 5- to 9-year-old children whose parents smoke and comparable children whose parents do not smoke? Pulmonary Disease A possible important...
Suppose another investigator wants to reproduce the results of the Amish study. She can recruit 100 subjects with the II genotype and 100 subjects with the ID genotype. How much power will the study...
Refer to Exercise 22.4. Set up the opportunity loss table. In exercise 22.4 Given the following payoff table, draw the decision tree: -1 4 10 S1 S2 S3 20 -10
An order for an automobile can specify either an automatic or a standard transmission, either with or without air conditioning, and with any one of the four colors red, blue, black, or white....
Perform the test in Problem 8.112, and report a p-value (two-tailed)? Microbiology A study sought to demonstrate that soy beans inoculated with nitrogen-fixing bacteria yield more and grow adequately...
Suppose there is some overlap between the 95% CIs in Problem 8.110. Does this necessarily imply there is no significant difference between the mean pod weights for the two groups? Why or why not?...
Provide a 95% CI for the mean pod weight in each group? Microbiology A study sought to demonstrate that soy beans inoculated with nitrogen-fixing bacteria yield more and grow adequately without the...
Implement the test in Problem 9.47, and report a twotailed p-value? Table 9.15: (Weight change, control period) (weight change, lack-of-consistency period) among 23 adolescent diabetic boys 4, A....
What significance test can be used to assess whether there is a relationship between receiving an antibiotic and receiving a bacterial culture while in the hospital? Refer to Table 2.13 (p. 36)....
Are the present diagnosis and prior episodes of urethritis associated? Sexually Transmitted Disease Suppose researchers do an epidemiologic investigation of people entering a sexually transmitted...
Provide a point estimate and a 95% confidence interval for the prevalence of otorrhea at 2 weeks in the observation group? Otolaryngology Many children have tympanostomy tubes surgically inserted in...
Perform the test in Problem 10.21 and report a p-value (two-tailed). Interpret your results in words? Otolaryngology Many children have tympanostomy tubes surgically inserted in their ears to reduce...
Based on all matched pairs, how much power did the study just mentioned have vs. the alternative hypothesis that a widower is twice as likely to die before a married person of the same age and...
Implement the test in Problem 10.74, and report a p-value? Zoology A study was performed to look at the preference of different species of birds for different types of sunflower seeds. Two bird...
Suppose that we conduct a test of significance using 5% as our level of significance. a. What is the probability of making a Type I error (if the null hypothesis is true)? b. Suppose we conduct 10...
What test can be performed to study the association between case/control status and risk score? Specifically, we are interested in testing whether cases tend to have consistently higher risk scores...
Fit a regression line relating 5-year lung-cancer mortality to annual cigarette consumption when each is expressed in the log 10 scale? Cancer The following statistics are taken from an article by...
To test the significance of this regression line, is it necessary to perform any additional tests other than those in Problem 11.20? If so, perform them. Cancer The following statistics are taken...
Use ANOVA methods to estimate the CV for plasma beta-carotene for the 23 participants, based on the two baseline measurements? Table 12.35: Format of BETACAR.DAT Code Variable Column Preparation...
Which of the following is the primary purpose of randomly assigning subjects to treatments in an experiment? A. To produce similar (experimental) groups so any differences in the response variable...
Summarize the findings in a few sentences, and compare them with the results in Problem 12.62? Hypertension Refer to Table 12.16 (on page 595). A similar ANCOVA was performed using PROC GLM of SAS...
Is this an observational study or an experiment? How are you deciding? The researcher is now interested in seeing whether a higher proportion of men in the group that crossed the Capilano Canyon...
Perform a significance test to examine the association between OC use and bacteriuria after controlling for age? Refer to Table 13.8. Risk of bacteriuria among OC users and nonusers % with...
Fill in the cells in the following table so there is no association between the explanatory and response variables. Female Total Male Played sports in high school Yes 200 160 No Total 150 210 360
Fill in the cells in the following table so there is no association between the explanatory and response variables. Member of Fraternity or Sorority Yes No Total Yes 152 Has one or more alcoholic...
What do these statistical tests mean in this instance? Cardiovascular Disease Sudden death is an important, lethal cardiovascular endpoint. Most previous studies of risk factors for sudden death have...
Assess whether there are any significant treatment or carry-over effects of SBP or DBP in study 1? Three separate two-period cross-over studies were performed, based on different groups of subjects....
Is there a significant association between MI and severe vertex baldness after controlling for age? Please report a two-tailed p-value. Cardiovascular Disease A study was performed relating baldness...
Approximately what does the box portion of a boxplot display? A. The middle quarter of the data B. The middle half of the data C. The lower quarter of the data D. The upper quarter of the data
On a data set that is bell-shaped, which will typically be larger, its standard deviation or its inter-quartile range?
Using the candy bar weight data shown in the previous exercise, do the following: a. Find the five-number summary for both sets of candy bar weights. b. Construct parallel boxplots for both sets of...
Reconsider the previous exercise about haircut prices. The p-value for the appropriate test turns out to be 0.0022. What would you conclude? (Circle all that apply.) A. The sample data provide strong...
Provide a two-sided 95% CI for incidence rate of flu among high-risk students during winter 20082009? Infectious Disease Suppose the incidence rate of influenza (flu) during the winter of 20082009...
Refer to Exercise 6.16. The numbers (in millions) of Americans speaking non-English languages at home are listed next. If one individual is selected at random find the probability of the following...
What is the difference between paired design using repeated measures and paired design using matching?
Suppose that you want to determine whether there is a difference between the distances traveled by two different brands of golf balls. You use the 30 people on your golf league to participate in the...
Most televised baseball games display a pitch tracker that shows whether the pitch was in the strike zone, which in turn shows whether the umpire made the correct call. Major League Baseball keeps...
Study after study indicate that men earn higher incomes than women (SEX: 1 = Male, 2 = Female). a. To determine the extent of the differential in 2014 estimate the difference between male and female...
Match the appropriate test of significance to each of the following research questions. 1. Testing a single proportion 2. Testing a single mean 3. Comparing two proportions 4. Comparing two means...
A researcher measures body flexibility in college students. She suspects that females will be more flexible than males. a. State the null and alternative hypotheses. b. Identify the explanatory and...
Find the probabilities. 1. P(Z < 1.60) 2. P(Z < 1.61) 3. P(Z < 1.65) 4. P(Z < 1.39) 5. P(Z < 1.80) 6. P(Z < 2.16) 7. P(1.30 < Z < .70) 8. P(Z > 1.24) 9. P(Z < 2.23) 10. P(Z > 1.87) 11. P(Z < 2.57)...
Which of the following are true about the MAD statistic? There may be more than one statement that is true. a. The MAD statistic can never be negative. b. The MAD statistic is the average distance...
The breakdown of U.S. cities having a population of at least 10,000 persons has been reported as follows. a. How many cities have a population of at least 25,000 but less than 500,000? b. How many...
The International Council of Shopping Centers reports that the average teenager spends $39 during a shopping trip to the mall. The promotions director of a local mall has used a variety of strategies...
If you took repeated samples of size 150 and constructed a 99% confidence interval for the population mean of hours slept from each sample, what percentage of these intervals would capture the...
The dotplot generated below by the One Proportion applet assumed the long-run proportion of winning was equal to 50%. Use this dotplot to answer the following questions. a. How many dots are in the...
Janine serves 30 short serves with her right hand and gets 17 of the 30 in the court. a. What are two possible explanations for Janine getting 17 out of 30 right-handed short serves in? b. Which of...
A chimpanzee named Sarah was the subject in a study of whether chimpanzees can solve problems. Sarah was shown 30-second videos of a human actor struggling with one of several problems (for example,...
An international manufacturer of electronic products is contemplating introducing a new type of compact disk player. After some analysis of the market, the president of the company concludes that,...
Use the One Proportion applet to simulate 1,000 repetitions of this study, assuming that every driver is just as likely to talk on the cell phone as not while driving. Report what values you input...
An article in The Journal of Data Science [A Statistical Analysis of Well Failures in Baltimore County (2009, Vol. 7, pp. 111127)] provided the following table of well failures for different...
What has to be true about the observed proportions if the MAD statistic is zero?
Summarize the findings from the study. What worked well in this study design? What would you change? What are some follow-up research questions you would like to explore based on the findings from...
Are you able to conclude that the association between hand span and number of Tootsie Rolls grabbed is causal? Explain. Is hand span a good predictor of how much candy you can grab? Using 45 college...
Consider the bar code 39 is a common bar code system that consists of narrow and wide bars (black) separated by either wide or narrow spaces (white). Each character contains nine elements (five bars...
For a given data set, a test of association based on a slope is equivalent to a test of association based on a correlation coefficient. Being equivalent means which of the following is true? A. The...
Which of the following does the method of least squares minimize? A. Sum of vertical distances between observations and the line B. Sum of squared vertical distances between observations and the line...
Reconsider the previous two exercises about textbook prices. Th e equation of the least squares regression line for predicting price from number of pages is price = 14.11 + 0.13 (pages). a. Interpret...
a. Identify the parameter of interest for this study and assign a symbol to it. b. If Krieger is just randomly choosing between the two objects, what is the chance that he will choose the correct...
Find a solution of x dy/dx = y 2 - y that passes through the indicated points. (a) (0, 1) (b) (0, 0) (c) (12, ) (d) (2, )
Evaluate the strength of evidence for the hypotheses in the previous question. a. Find the p-value for the hypotheses in the previous question using a simulation-based approach. b. Based on the...
Consider the gain estimation problem in Exercise 8-4. (a) How large must n be if the length of the 95% CI is to be 40? (b) How large must n be if the length of the 99% CI is to be 40?
Use the data from Exercise 8-68 to compute a two-sided Agresti-Coull CI on the proportion of seeds that germinate. Compare and discuss the CI to the one computed in Exercise 8-68.
On January 28, 1986, the Space Shuttle Challenger broke apart 73 seconds into its flight, killing all seven astronauts on board. All investigations into reasons for the disaster pointed towards the...
Reconsider Dr. Sameers research question about how much time Cal Poly students spend on watching television. Suppose that Dr. Sameer surveys a random sample of 100 Cal Poly students, and for this...
Consider a manufacturing process that is producing hypodermic needles that will be used for blood donations. These needles need to have a diameter of 1.65 mmtoo big and they would hurt the donor...
Is there evidence to suggest that the standard deviations of the algae concentrations in the two types of rivers (flow rates) in Exercise 10-36 differ? Use = 0.05.
Consider a multiple regression model with k regressors. Show that the test statistic for significance of regression can be written as Suppose that n = 20, k = 4, and R 2 = 090. If = 0.05, what...
Find the general solution of the given differential equation. Give the largest interval I over which the general solution is defined. Determine whether there are any transient terms in the general...
Determine whether the given differential equation is exact. If it is exact, solve it. (2x - 1) dx + (3y + 7) dy = 0
Suppose that a table of part counts is generalized as follows: where a, b, and k are positive integers. Let A denote the event that a part is from supplier 1, and let B denote the event that a part...
The differential equation dp/dt = (k cost)P, where k is a positive constant, is a model of human population P(t) of a certain community. Discuss an interpretation for the solution of this equation....
A test instrument needs to be calibrated periodically to prevent measurement errors. After some time of use without calibration, it is known that the probability density function of the measurement...
According to a 2011 report by the United States Department of Labor, civilian Americans spend 2.75 hours per day watching television. A faculty researcher, Dr.Sameer, at California Polytechnic State...
The t test for comparing two means is to the Wilcoxon test (for independent samples) as the matched pairs t test is to the __________ (for dependent samples in matched pairs).
A Gallup survey of 1001 randomly selected U.S. adults conducted May 2011 asked, In your opinion, which one of the following is the main reason why students get education beyond high school?...
When a vertical beam of light passes through a transparent medium, the rate at which its intensity I decreases is proportional to I(t), where t represents the thickness of the medium (in feet). In...
A small metal bar, whose initial temperature was 20 C, is dropped into a large container of boiling water. How long will it take the bar to reach 90 C if it is known that its temperature increases 2...
A thermometer reading 70 F is placed in an oven preheated to a constant temperature. Through a glass window in the oven door, an observer records that the thermometer reads 110 F after 12 minute and...
The following segmented bar graph was produced from data collected in the 2010 General Social Survey with regard to the question Can people be trusted? a. About what proportion of the liberals...
In 1973 a lawsuit was filed against the University of California at Berkeley, alleging sex discrimination in its graduate admissions policies. The following table pertains to two of the graduate...
Reconsider the exercise in Section 5.1 about Medicare audits (5.1.6). Of the 30 small claims, 14 were judged to be over payments; of the 30 medium claims, 8 were judged to be overpayments. Our...
In problem find the general solution of the given higher order differential equation. y (4) + y''' + y'' = 0
Reconsider the data from the previous exercise about investigating whether giving chest-compression-only (CC) instructions rather than standard cardiopulmonary resuscitation (CPR) instructions to the...
A survey of 1507 smartphone users showed that 38% of them purchased insurance at the same time as they purchased their phones. Determine whether descriptive or inferential statistics were used.
Time magazine reported that 83% of people with household earnings over $200,000 have a bachelors degree. Define a population that may have been used and explain how the sample might have been...
The average number of pupils per teacher in each state is shown. Construct a grouped frequency distribution with 6 classes. Draw a histogram, frequency polygon, and ogive. Analyze the distribution....
Construct a histogram, frequency polygon, and ogive for the data in Exercise 6. Data from 6 79 70 71 63 83 90 72 66 80 73 68 70 51 66 74 67 54 81 62 66 78 68 57 96 78 55 76 60 85 71 66 57 77 88 93 70...
Reconsider the data in the dotplot in the previous question about the number of states that students had visited. Suppose the observation recorded as 43 states is a typo and was meant to be 34. If we...