Concept explainers
Pneumonia Vaccine for Young Children A study reported by Griffin et al. compared the rate of pneumonia between 1997 and 1999 before pneumonia vaccine (PCV7) was introduced and between 2007 and 2009 after pneumonia vaccine was introduced. Read the excerpts from the abstract, and answer the question that follows it. (Source: Griffin et al., “U.S. hospitalizations for pneumonia after a decade of pneumococcal vaccination,” New England Journal of Medicine, vol. 369 [July 11, 201]: 155-163)
We estimated annual rates of hospitalization for pneumonia from any cause using the Nationwide Inpatient Sample database. . . . Average annual rates of pneumoniarelated hospitalizations from 1997 through 1999 (before the introduction of PCV7) and from 2007 through 2009 (well after its introduction) were used to estimate annual declines in hospitalizations due to pneumonia.
The annual rate of hospitalization for pneumonia among children younger than 2 years of age declined by 551.1 per 100,000 children . . . which translates to 47,000 fewer hospitalizations annually than expected on the basis of the rates before PCV7 was introduced.
Results for other age groups were similar. Does this show that pneumonia vaccine caused the decrease in pneumonia that occurred? Explain.
Want to see the full answer?
Check out a sample textbook solutionChapter 1 Solutions
Introductory Statistics
Additional Math Textbook Solutions
Elementary Statistics: Picturing the World (7th Edition)
Math in Our World
Elementary & Intermediate Algebra
Precalculus
Precalculus: Mathematics for Calculus (Standalone Book)
APPLIED STAT.IN BUS.+ECONOMICS
- Urban Travel Times Population of cities and driving times are related, as shown in the accompanying table, which shows the 1960 population N, in thousands, for several cities, together with the average time T, in minutes, sent by residents driving to work. City Population N Driving time T Los Angeles 6489 16.8 Pittsburgh 1804 12.6 Washington 1808 14.3 Hutchinson 38 6.1 Nashville 347 10.8 Tallahassee 48 7.3 An analysis of these data, along with data from 17 other cities in the United States and Canada, led to a power model of average driving time as a function of population. a Construct a power model of driving time in minutes as a function of population measured in thousands b Is average driving time in Pittsburgh more or less than would be expected from its population? c If you wish to move to a smaller city to reduce your average driving time to work by 25, how much smaller should the city be?arrow_forwardWhat is an experiment?arrow_forwardTourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel, May 19, 2018). Hotel occupancy data for February in two consecutive years are as follows. Current Year 1,394 1,700 Occupied Rooms Total Rooms a. Formulate the hypothesis test that can be used to determine whether there has been an increase in the proportion of rooms occupied over the one-year period. Let p₁ = population proportion of rooms occupied for current year P2 = population proportion of rooms occupied for previous year 0.82 Previous Year 1,404 1,800 Ho: P1 P2 less than or equal to 0 Ha P₁ P2 greater than 0 b. What is the estimated proportion of hotel rooms occupied each year (to 2 decimals)? Current year Previous Year c. Conduct a hypothesis test. What is the p-value (to 4 decimals)? Use Table 1 from Appendix B. 0.78arrow_forward
- Tourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel, May 19, 2018). Hotel occupancy data for February in two consecutive years are as follows. Current Year Previous Year Occupied Rooms 1,584 1,445 Total Rooms 1,800 1,700 a. Formulate the hypothesis test that can be used to determine whether there has been an increase in the proportion of rooms occupied over the one-year period. Let pi population proportion of rooms occupied for current year P2 = population proportion of rooms occupied for previous year Ho : P1 - P2 - Select your answer - Ha : P1 – P2 - Select your answer - b. What is the estimated proportion of hotel rooms occupied each year (to 2 decimals)? Current year Previous Year c. Conduct a hypothesis test. What is the p-value (to 4 decimals)? Use Table 1 from Appendix B. p-value = Using a 0.05 level of significance, what is your conclusion? We -Select your answer - that…arrow_forwardA better drug? In a pilot study, a company's new cholesterol-reducing drug outperforms the currently available drug. If the data provide convincing evi- dence that the mean cholesterol reduction with the new drug is more than 10 milligrams per deciliter of blood (mg/dl) greater than with the current drug, the company will begin the expensive process of mass-producing the new drug. For the 14 subjects who were assigned at random to the current drug, the mean cholesterol reduction was 54.1 mg/dl with a standard deviation of 11.93 mg/dl. For the 15 sub- jects who were randomly assigned to the new drug, the mean cholesterol reduction was 68.7 mg/dl with a standard deviation of 13.3 mg/dl. Graphs of the data reveal no outliers or strong skewness. Carry out an appropriate significance test. What conclusion would you draw? (Note that the null hypothesis is not Ho: μμ2=0.) Based on your conclusion in part (a), could you have made a Type I error or a Type II error? Justify your answer.arrow_forwardA researcher conducts a study to investigate whether the obesity rate rural communities differ from the obesity rate from the population at large. He gathered a sample of adults from a small community, measured their weight, and compared it to the population average. What statistical test is appropriate for this study and why?arrow_forward
- Tourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel, May 19, 2018). Hotel occupancy data for February in two consecutive years are as follows. Previous Year Occupied Rooms Total Rooms Current Year 1,505 1,750 1,577 1,900 a. Formulate the hypothesis test that can be used to determine whether there has been an increase in the proportion of rooms occupied over the one-year period. Let P₁ = population proportion of rooms occupied for current year P2 = population proportion of rooms occupied for previous year Ho: P1 P2 less than or equal to 0 Ha P₁ P2 greater than 0 b. What is the estimated proportion of hotel rooms occupied each year (to 2 decimals)? Current year Previous Year c. Conduct a hypothesis test. What is the p-value (to 4 decimals)? Use Table 1 from Appendix B. p-value = Using a 0.05 level of significance, what is your conclusion? We can conclude that there has been an…arrow_forwardRecent research indicates that the effectiveness of antidepressant medication is directly related to the severity of the depression (Khan, Brodhead, Kolts & Brown, 2005). Based on pretreatment depression scores, patients were divided into four groups based on their level of depression. After receiving the antidepressant medication, depression scores were measured again and the amount of improvement was recorded for each patient. The following data are similar to the results of the study. LowModerate HighModerate ModeratelySevere Severe 0.5 2.7 3.4 2.6 1.7 0.8 2.6 5.3 3.3 1.9 1.1 4 2.6 1.4 4.3 2.6 1.4 2.9 3.6 4.6 3.1 3.2 4.8 1.4 From this table, conduct an one-way ANOVA. Calculate the F-ratio and p-value. Be sure to round your answers to three decimal places. Assume all population and ANOVA requirements are met.F-ratio: p-value:arrow_forwardRecent research indicates that the effectiveness of antidepressant medication is directly related to the severity of the depression (Khan, Brodhead, Kolts & Brown, 2005). Based on pretreatment depression scores, patients were divided into four groups based on their level of depression. After receiving the antidepressant medication, depression scores were measured again and the amount of improvement was recorded for each patient. The following data are similar to the results of the study. LowModerate HighModerate ModeratelySevere Severe 2.4 0.2 2.5 3.5 1.6 1.7 2.7 4.3 2.7 3.4 2 3.4 0.5 1.2 5.2 5.1 2.4 2.3 4 3.5 1.8 0.3 4.1 3.8 From this table, conduct an one-way ANOVA. Calculate the F-ratio and p-value. Be sure to round your answers to three decimal places. Assume all population and ANOVA requirements are met.F-ratio: _____p-value: _____What is your final conclusion? Use a significance level of α=0.05. (Select one): There is sufficient evidence that…arrow_forward
- Recent research indicates that the effectiveness of antidepressant medication is directly related to the severity of the depression (Khan, Brodhead, Kolts & Brown, 2005). Based on pretreatment depression scores, patients were divided into four groups based on their level of depression. After receiving the antidepressant medication, depression scores were measured again and the amount of improvement was recorded for each patient. The following data are similar to the results of the study. LowModerate HighModerate ModeratelySevere Severe 2.2 1.4 3.4 3.4 1.5 1.4 3.5 2.8 2.8 3.1 2.7 2.3 1.7 2.6 4.4 3.6 1.3 1.5 2.6 3.2 1.3 2.6 2.8 3.5 Fill in the summary table for the ANOVA test: degrees of freedom (d.f.) Sum of Squares (S.S.) Mean Square (M.S.) Between Within Total From this table, obtain the necessary statistics for the ANOVA:F-ratio (F-test statistic): p-value: η2η2 (Eta squared = Sum of squares betweenSum of squares totalSum…arrow_forwardTourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel, May 19, 2018). Hotel occupancy data for February in two consecutive years are as follows. Current Year Previous Year Occupied Rooms 1,360 1,386 Total Rooms 1,700 1,800 a. Formulate the hypothesis test that can be used to determine whether there has been an increase in the proportion of rooms occupied over the one-year period. Let pi = population proportion of rooms occupied for current year Pa= population proportion of rooms occupied for previous year Ho : Pi - Pa H.: Pi - P2 Select your answer Select your answer b. What is the estimated proportion of hotel rooms occupied each year (to 2 decimals)? Current year Previous Year c. Conduct a hypothesis test. What is the p-value (to 4 decimals)? Use Table 1 from Appendix B. p-value - Using a 0.05 level of significance, what is your conclusion? We Select your answer- vthat there has…arrow_forwardTourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel, May 19, 2018). Hotel occupancy data for February in two consecutive years are as follows. Current Year Previous Year Occupied Rooms 1,470 1,377 Total Rooms 1,750 1,700 a. Formulate the hypothesis test that can be used to determine whether there has been an increase in the proportion of rooms occupied over the one-year period. Let pi population proportion of rooms occupied for current year P2 population proportion of rooms occupied for previous year Ho : P1 - P2 - Select your answer - На : р1 P2 - Select your answer - b. What is the estimated proportion of hotel rooms occupied each year (to 2 decimals)? Current year Previous Year c. Conduct a hypothesis test. What is the p-value (to 4 decimals)? Use Table 1 from Appendix B. p-value %3D Using a 0.05 level of significance, what is your conclusion? We - Select your answer - v that…arrow_forward
- Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage LearningLinear Algebra: A Modern IntroductionAlgebraISBN:9781285463247Author:David PoolePublisher:Cengage LearningGlencoe 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