Concept explainers
Although tea is the world’s most widely consumed beverage after water, little is known about its nutritional value. Folacin is the only B vitamin present in any significant amount in tea, and recent advances in assay methods have made accurate determination of folacin content feasible. Consider the accompanying data on folacin content for randomly selected specimens of the four leading brands of green tea. folacin content for randomly selected specimens of the four leading brands of green tea.
1: | 7.9 | 6.2 | 6.6 | 8.6 | 8.9 | 10.1 9.6 |
2: | 5.7 | 7.5 | 9.8 | 6.1 | 8.4 | |
3: | 6.8 | 7.5 | 5.0 | 7.4 | 5.3 | 6.1 |
4: | 6.4 | 7.1 | 7.9 | 4.5 | 5.0 | 4.0 |
(Data is based on "Folacin Content of Tea,” J. of the Amer. Dietetic Assoc., 1983: 627-632.) Does this data suggest that true average folacin content is the same for all brands?
a. Carry out a test using α = .05.
b. Assess the plausibility of any assumptions required for your analysis in part (a).
c. Perform a multiple comparisons analysis to identify significant differences among brands.
Trending nowThis is a popular solution!
Chapter 10 Solutions
Probability and Statistics for Engineering and the Sciences
- A U.S. Food Survey showed that Americans routinely eat beef in their diet. Suppose that in a study of 49 consumers in Illinois and 64 consumers in Texas the following results were obtained from two samples regarding average yearly beef consumption: Illinois Texas = 49 = 64 = 54.1lb = 60.4lb S1 = 7.0 S2 = 8.0 What is the appropriate Test statistic? Name it and Compute its value.arrow_forwardAs an occupational health epidemiologist you are required to measure the effect of stress on the workers in your manufacturing plant. Two different tests previously developed to measure stress in industrial workers are selected: stress test alpha and stress test delta. The sensitivity and specificity of each test are shown below. Which test generates the greatest proportion of false negatives? Stress Test Alpha Stress Test Delta Sensitivity = 60% 75% M Specificity = 95% 90% Stress Test Alpha Stress Test Deltaarrow_forwardCheek teeth of extinct primates. The characteristics of cheek teeth (e.g., molars) can provide anthropologists with information on the dietary habits of extinct mammals. The cheek teeth of an extinct primate species were the subject of research reported in the American Journal of Physical Anthropology (Vol. 142, 2010). A total of 18 cheek teeth extracted from skulls discovered in western Wyoming were analyzed. Researchers recorded the dentary depth of molars (in millimeters) for a sample of 18 cheek teeth extracted from skulls. These depth measurements are listed in the accompanying table. Anthropologists know that the mean dentary depth of molars in an extinct primate species— called Species A—is 15 millimeters. Is there evidence to indicate that the sample of 18 cheek teeth come from some other extinct primate species (i.e., some species other than Species A)? The data are given below (you will need to put it into a single column). You will need to calculate the sample…arrow_forward
- Benzene is a pollutant that, according to studies, can be associated with health problems. Benzene is found in air, water, and soil and comes from both industrial and natural sources. Benzene levels in indoor air are generally higher than outdoors. The main source of benzene in indoor air appears to be tobacco smoke, thus the combustion of tobacco is a major source of pollution. Benzene levels are measured in a random sample of 36 bars in a city, obtaining an average benzene level of 19.2 mg / m3, with a standard deviation of 2.1 mg / m3. Estimate the mean benzene level in bars in this city using a 95% confidence interval. (do your calculations to 4 decimal places) (need the process can be by hand ,Excel or R.) a)Other solution b)[18.48946, 19.91054] c)[19.0950, 19.3050] d)[18.5140, 19.8859] e)[18.6243, 19.7757] f)[18.4315, 19.7936]arrow_forwardA researcher is interested in determining whether course delivery mode (online v on-ground) has had an effect on students' final exam scores. Below are the scores for each group. Conduct a two-samples t-test to determine if there is a significant difference between average scores in both groups. Assume alpha =0.05 Copy/paste the data below into an Excel Sheet (or Google Sheets) and run a two-samples t-test. Copy/paste the results into the response window below. Be sure to include your interpretation of the results. In your answer, state the null and the research hypotheses and explain whether the results of the two-sample test led you to reject or fail…arrow_forwardThe background concentration of a chemical in soil was measured on ten random specimens of soil from an uncontaminated area. The measured concentrations, in mg/kg, are: 1.4, 0.6, 1.2, 1.6, 0.5, 0.7, 0.3, 0.8, 0.2, and 0.9. Soil from a neighboring area will be declared “contaminated” if test specimens contain a chemical concentration higher than the upper 99% confidence limit of the background level. What is the cleanup target concentration?arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill