In each of Exercises 11.33–11.36, use the technology of your choice to decide whether applying one-standard-deviation χ2-procedures appears reasonable. Explain your answers.
11.36 Plesiadapis cookei. One extinct relative of primates that lived in North America about 60 million years ago is called Plesiadapis cookei. Dental characteristics of P cookei were compared to those of other primate species in the article ‘‘Evidence of Dietary Differentiation among Late Paleocene-Early Eocene Plesiadapids" (American Journal of Physical Anthropology, Vol. 142, No. 2, pp. 194–210) by D. Boyer el al. The following table gives the dentary depth, in millimeters, for a sample of molars from the skulls of 18 P cookei specimens.
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Introductory Statistics (10th Edition)
- A random sample of 15 families representing three different Scandinavian countries has been observed for the number of weekend trips they take per year. Are the differences significant (use p=.05, F(critical) = 3.88)? Use the five step model as a guide and write a sentence or two of interpretation for your results. Sweden Norway Denmark 10 11 7 9 10 5 4 5 2 2 2 0arrow_forwardRecent results suggest that children with ADHD tend to watch more TV than children who are not diagnosed with the disorder. To examine this relationship, a researcher obtains a random sample of n = 36 children, 8 to 12 years old, who have been diagnosed with ADHD. Each child is asked to keep a journal recording how much time each day is spent watching TV. The average daily time for the sample is M = 4.9 hours. It is known that the average time for the general population of 8 to 12-year-old children is = 4.1 hours with = 1.8. (Hint: Be sure to use the correct test statistic). Are the data sufficient to conclude that children with ADHD watch significantly more TV than children without the disorder? Use a two-tailed test with = .05. (Be sure to give your conclusion, too) If the researcher had used a sample of n = 9 children and obtained the same sample mean, would the results be sufficient to reject H0? (Be sure to give your conclusion, too) Compute Cohen's d for this study. What is…arrow_forwardAn 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 52 43 Intermediate 55 44 Full sized 61 45 Use ? = 0.05 to test for any significant differences. State the null and alternative hypotheses. H0: ?Compact ≠ ?Intermediate ≠ ?Full-sizedHa: ?Compact = ?Intermediate = ?Full-sized H0: ?Compact = ?Intermediate = ?Full-sizedHa: ?Compact ≠ ?Intermediate ≠ ?Full-sized H0: ?Computerized = ?Electronic = ?Compact = ?Intermediate = ?Full-sizedHa: Not all the population means are equal. H0: ?Computerized ≠ ?ElectronicHa: ?Computerized = ?Electronic H0: ?Computerized = ?ElectronicHa: ?Computerized ≠ ?Electronic Find the…arrow_forward
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- Evans conducted a study to determine if the frequency and characteristics of pediatric problems in elderly patients with diabetes present differences with respect to patients of the same age, but without diabetes. The individuals studied, interned in a clinic, were between 70 and 90 years old. Among the researchers' findings are the following statistics. with respect to the scores on the deep tendon reflexes meters:Sample without Diabetes: 79 / 2.1 / 1.1With Diabetes: 74 / 1.6 / 1.2Is it possible to conclude, based on the data, that, on average, diabetic patients they have reduced deep tendon reflexes in comparison with patients without diabetes of the same age?arrow_forwardA randc v ection of volunteers at a research institute have been exposed to a typical cold virus. After they started to have cold symptoms, 15 of them were given multivitamin tablets daily which contain 3 grams of vitamin C and various other vitamins and minerals. The remaining 15 volunteers were given placebo tablets. For each individual, the length of time taken to recover from cold is recorded. At the end of the experiment following data are obtained: Days to recover from cold Treated with multivitamin 3.0, 3.2, 6.3, 3.8, 5.8, 7.3, 5.3, 5.7, 7.9, 5.7, 6.2, 4.3, 3.8, 6.1, 4.6 Treated with placebo 7.1, 5.9, 5.5, 5.2, 2.4, 3.7, 4.9, 3.5, 4.3, 6.6, 4.5, 3.2, 3.4, 4.1, 2.9 Send data to calculator v It is known that the population standard deviation of recovery time from cold is 1.8 days when treated with multivitamin, and the population standard deviation of recovery time from cold is 1.5 days when treated with placebo tablets. It is also known that both populations are approximately…arrow_forwardA clinical study was conducted on a medicine and the data obtained as follows: calculate Sensitivity Diseased •True Positive: 1000 •True negative: 50 Non diseased •True positive: 100 •True negative: 800arrow_forward
- Dioxin Researchers have linked an increase in the inci-dence of breast cancer in Italy to dioxin released by an industrial accident in 1976. The study identified 981women who lived near the site of the accident and were under age 40 at the time. Fifteen of the women had devel-oped breast cancer at an unusually young average age of 45. Medical records showed that they had heightened con-centrations of dioxin in their blood and that each tenfold increase in dioxin level was associated with a doubling ofthe risk of breast cancer. (Science News, Aug. 3, 2002)arrow_forwardAn 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 51 42 Car Intermediate 54 44 Full-sized 63 46 Use a = 0.05 to test for any significant differences. State the null and alternative hypotheses. O Ho: Camputerized = HElectronic H: "Computerized * HElectronic O Ho: HCamputerized * HElectronic H: "Computerized = "Electronic O Ho: "Compact = "Intermediate = "Full-sized Ha: "Compact * HIntermediate * HFull-sized O Ho: HComputerized = "Electronic = "Compact = "Intermediate = "Full-sized H: Not all the population means are equal. O Ho: HCompact * "Intermediate * HFull-sized Ha: "Compact = "Intermediate = "Full-sized Find the value of the…arrow_forwardIn the article “The World's Longest Continued Series of Sea Level Observations” (M. Ekman, Paleogeography, 1988:73–77), the mean annual level of land uplift in Stockholm, Sweden, was estimated to be 4.93 ± 0.23 mm for the years 1774–1884 and to be 3.92 ± 0.19 mm for the years 1885–1984. Estimate the difference in the mean annual uplift between these two time periods, and find the uncertainty in the estimate.arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill