Suppose researchers use random assignment to create two groups of people who are all taking a certain drug at the same dosage each day.  The people are taking the drug in order to decrease the number of headaches they have each day.  Group A increases their dosage by 50% each day, while Group B acts as a control group and stays on the same original dosage.  Suppose the researchers conclude, at the end of the statistical analysis, that there is statistically significant evidence that Group A has a lower average number of headaches each day than Group B.  (a)  Which of the following conclusions can be drawn? Researchers can conclude that the results of this study can be generalized to the entire population since random assignment was used to make the groups. Researchers can conclude that increasing the dosage caused the average number of headaches to decrease since random assignment was used to make the groups.   (b)  Identify (describe in words) the explanatory variable. (c) Identify (describe in words) the response variable.

. A researcher suspects that the actual prevalence of generalized anxiety among children and adolescents is higher than the previously reported prevalence of generalized anxiety disorder among children and adolescents. The previously reported prevalence of generalized anxiety disorder among children and adolescents is 4.1%, and the researcher conducts a study to test the accuracy of the previously reported prevalence of generalized anxiety disorder by recruiting 98 children and adolescents from various pediatricians’ offices and tests them for generalized anxiety disorder using the DSM-5. The researcher determines that the prevalence of generalized anxiety disorder among the participants of the study is 6.8%. The researcher’s hypothesis, for a level of significance of 5%, should resemble which of the following sets of hypothesis? A) H0: p > .041; H1: p = .041; alpha= .05 B) H0: p > .041; H1: p = .041; alpha= .95 C) H0: p = .041; H1: p > .041; alpha= .05 D) H0: p = .041; H1: p…

It has been found that 25.1% of men (Group 1) 20 years and older suffer from hypertension (high blood pressure) and 33.9% of women (Group 2) are hypertensive. A random sample of 164 of each gender was selected from recent hospital records, and the following results were obtained. Can you conclude that a higher percentage of women have high blood pressure? Use =0.05. Men: 42 patients had high blood pressure Women: 52 patients had high blood pressure   Required: Test Value Only the final answer should be rounded-off to TWO decimal places.

A study prospectively examined whether sleep-disordered breathing was associated with an increased risk of death from any cause in a cohort of 600 adults participating in the Sleep Heart Health Study. Study participants were classified into four groups depending on the extent of their sleep-disordered breathing (none, mild, moderate, or severe). The counts of deaths over the course of the study are reported for each group in the following two-way table. Mild Severe 100 Death No Death Total None 40 100 140 40 100 140 Moderate 20 100 120 Total 200 400 600 100 200 We want to know whether the study findings give evidence of a significant difference of the number of deaths between the different groups. Set up the alternative hypothesis (H, : The distribution of the categorical variable is not as given by the null hypothesis (lack of fit) At least ones of the means is different from the others O The two categorical variables are dependent The distribution of the categorical variable is not…

A study prospectively examined whether sleep-disordered breathing was associated with an increased risk of death from any cause in a cohort of 600 adults participating in the Sleep Heart Health Study. Study participants were classified into four groups depending on the extent of their sleep-disordered breathing (none, mild, moderate, or severe). The counts of deaths over the course of the study are reported for each group in the following two-way table. Death No Death Total None 40 100 140 Mild 40 100 140 Moderate 20 100 120 Severe 100 100 200 Total 200 400 600 We want to know whether the study findings give evidence of a significant difference of the number of deaths between the different groups. The observed test statistic is 3.610 42.857 5.476 8.075

Recent research findings have shown that older people who practice ballroom dancing are 77% less likely to experience dementia compared to those senior citizens who did not dance. Drawing on this surprising result, Dr. Anders Ericsson thinks that ballroom dancing may also reduce one's level of stress to a greater extent than conventional exercise routines. To validate his claim Dr. Ericsson has randomly selected 100 senior citizens who were then randomly split into two groups, with the first group practicing ballroom dancing 3 times a week and the second group undergoing a conventional exercise regiment 3 times a week also. The measures of stress were assessed for each participant after the study was completed. What is the most appropriate set of hypotheses for this study? HO: μD- 0; H1: μD 0 HO: µD = 0; H1: µD > 0 %3D HO: udance - pexercise = 0; H1: µdance - pexercise <0

As a hospital administrator of a large hospital, you are concerned with the absenteeism among nurses' aides. The issue has been raised by registered nurses, who feel they often have to perform work normally done by their aides. To get the facts, absenteeism data were gathered for the last three weeks, which is considered a representative period for future conditions. After taking random samples of 64 personnel files each day, the following data were produced: Because your assessment of absenteeism is likely to come under careful scrutiny, you would like a type I error of only 1 percent. You want to be sure to identify any instances of unusual absences. If some are present, you will have to explore them on behalf of the registered nurses. a. Design a p-chart. The upper control limit is enter your response here and the lower control limit is enter your response here . (Enter your responses rounded to three decimal places. If your answer for the lower control limit is negative, enter…

▾ Part 1 of 4 A pharmaceutical company claims their new diabetes medication results in less variance in a patient's glucose level than if the patient were on no medication at all. An endocrinologist wishes to test this claim. She divides participants randomly into two groups. Group A consists of 20 diabetics who received the medication; group B consists of 26 diabetics who received a placebo. After two weeks, the blood sugar level of each patient in each group was measured with the following results (in mg/dL): Group A: 77.8, 229.4, 199.9, 110.1, 180.2, 116.1, 139.7, 171.1, 37.4, 158.1, 88.4, 195.5, 246.1, 142.4, 178.1, 105.5, 179.6, 146.1, 78.8, 123.7 Group B: 124.5, 130.1, 136, 162.8, 113.4, 72.8, 142.6, 50.3, 179.8, 197, 230, 194.3, 171, 109.3, 114.4, 107.5, 114.7, 195.3, 127.7, 126.4, 85.6, 166.7, 182.3, 113.5, 216.7, 162.8 Perform a hypothesis test using a 6% level of significance to test the pharmaceutical company's claim. Step 1: State the null and alternative hypotheses. Ho:…

In 1972, half of a group of 111 low-income children from Chapel Hill, NC were randomly chosen for enrollment in an intensive pre-school program, while the other half were not enrolled in any preschool program.  30 years later the preschool group had a higher % attending college, higher average GPA for those who did attend college, and higher average wages than the non-preschool group.   Fill in the following table.   Is there a control treatment (and, if so, what is it)?   Is there any accounting for individual variation?   Is there repetition in the experiment?   Is the experiment reproducible?     Can we say with some confidence that preschool has some lasting effects on career outcomes?