Concept explainers
Laboratory measures of cardiovascular reactivity are receiving increasing attention. Much of the expanded interest is based on the belief that these measures, obtained under challenge from physical and psychological stressors, may yield a more biologically meaningful index of cardiovascular
TABLE 3.11 Classification of cardiovascular reactivity using an automated and a manual sphygmomanometer
If the population tested is representative of the general population, then what are the PV+ and PV− using this test?
Trending nowThis is a popular solution!
Chapter 3 Solutions
Fundamentals of Biostatistics
- What does the y -intercept on the graph of a logistic equation correspond to for a population modeled by that equation?arrow_forwardUrban 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_forwardRead the journal excerpt below:Exposure to light at night suppresses the physiologic production of melatonin, a hormone that has antiproliferative effects on intestinal cancers. Although observational studies have associated night-shift work with an increased risk of breast cancer, the effect of night-shift work on the risk of other cancers is not known. We examined the relationship between working rotating night shifts and the risk of colorectal cancers among female participants in the Nurses’ Health Study. We documented 602 incident cases of colorectal cancer among 78 586 women who were followed up from 1988 through 1998. Compared with women who never worked rotating night shifts, women who worked 15 years or more on rotating night shifts were 1.35 times more likely to develop colorectal cancer (95% CI = 1.03 to 1.77), adjusting for confounders. These data suggest that working a rotating night shift at least three nights per month for 15 or more years may increase the risk of…arrow_forward
- You may need to use the appropriate technology to answer this question. An automobile dealer conducted a test to determine if the time in minutes needed to complete a minor engine tune-up depends on whether a computerized engine analyzer or an electronic analyzer is used. Because tune-up time varies among compact, intermediate, and full-sized cars, the three types of cars were used as blocks in the experiment. The data obtained follow. Analyzer Computerized Electronic Compact 50 41 Car Intermediate 54 44 Full-sized 64 47 Use a = 0.05 to test for any significant differences. State the null and alternative hypotheses. O Ho: MCompact = "Intermediate = HFull-sized H: "Compact * "Intermediate * "Full-sized O Ho: "Compact * "Intermediate * HFull-sized H: "Compact "Intermediate = "Full-sized O Ho: Computerized = HElectronic H: "Computerized * HElectronic O Ho: "Computerized = HElectronic = "Compact = Intermediate = Full-sized H: Not all the population means are equal. O Ho: HComputerized *…arrow_forwardYou may need to use the appropriate technology to answer this question. An automobile dealer conducted a test to determine if the time in minutes needed to complete a minor engine tune-up depends on whether a computerized engine analyzer or an electronic analyzer is used. Because tune-up time varies among compact, intermediate, and full-sized cars, the three types of cars were used as blocks in the experiment. The data obtained follow. Analyzer computerized electronic Car compact 50 41 Intermediate 56 45 Full Sized 62 46 Use ? = 0.05 to test for any significant differences. State the null and alternative hypotheses. H0: ?Computerized = ?ElectronicHa: ?Computerized ≠ ?ElectronicH0: ?Computerized ≠ ?ElectronicHa: ?Computerized = ?Electronic H0: ?Computerized = ?Electronic = ?Compact = ?Intermediate = ?Full-sizedHa: Not all the population means are equal.H0: ?Compact = ?Intermediate = ?Full-sizedHa: ?Compact ≠ ?Intermediate ≠ ?Full-sizedH0:…arrow_forwardThe following data are representative of many studies examining the relationship between arousal and performance. The general result of these studies is that increasing the level of arousal (or motivation) tends to improve the level of performance. (You probably have tried to “psych yourself up” to do well on a task.) For very difficult tasks, however, increasing arousal beyond a certain point tends to lower the level of performance. (Your friends have probably advised you to “calm down and stay focused” when you get overanxious about doing well.) This relationship between arousal and performance is known as the Yerkes-Dodson law. Use a two-factor ANOVA with α = .05 to evaluate the significance of the main effects and the interaction (conduct all 4 steps!). Calculate the values to measure the effect size for any significant results. Describe the pattern of results. How does the level of arousal (motivation) affect performance?arrow_forward
- A psychologist believes that the age of an adolescent will have an impact on the number of phone calls made to the opposite sex (in heterosexual people) over the course of one month. They also suspect that gender of the adolescent will have an impact on the number of phone calls made to the opposite sex. Using the hypothetical data provided below, run your analyses in R to test whether age and gender impacts the number of phone calls an adolescent makes. Gender (Binary) Girl Boy Age Young Adolescents (11-14) 7, 2, 3, 5, 3 1, 2, 3, 2, 1 Older Adolescents (15-18) 15, 26, 19, 21, 18 10, 8, 5, 16, 9 1. Using R, run your analysis and include a screenshot. 2. Using R, run post-hoc tests and include a screenshot. 3. What do you conclude about the null hypothesis? 4. Create a plot of your interaction and include a screenshot. Explain what the plot is showing you about the p-values you calculated in your post-hoc test. 5. Explain what your…arrow_forwardA psychologist believes that the age of an adolescent will have an impact on the number of phone calls made to the opposite sex (in heterosexual people) over the course of one month. They also suspect that gender of the adolescent will have an impact on the number of phone calls made to the opposite sex. Using the hypothetical data provided below, run your analyses in R to test whether age and gender impacts the number of phone calls an adolescent makes. Gender (Binary) Girl Boy Age Young Adolescents (11-14) 7, 2, 3, 5, 3 1, 2, 3, 2, 1 Older Adolescents (15-18) 15, 26, 19, 21, 18 10, 8, 5, 16, 9 4. Create a plot of your interaction and include a screenshot. Explain what the plot is showing you about the p-values you calculated in your post-hoc test. 5. Explain what your p-values are telling you regarding the amount of phone calls made in adolescents based on age and gender.arrow_forward
- Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage LearningCalculus For The Life SciencesCalculusISBN:9780321964038Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.Publisher:Pearson Addison Wesley,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