MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Question
Identifying individuals with a high risk of Alzheimer's disease usually involves a lons
series of cognitive tests. However, researchers have developed a 7-Minute Screen, which
is a quick and easy way to accomplish the same goal. The question is whether the 7-
Minute Screen is as effective as the complete series of tests. To address this question,
Ijuin et al. (2008) administered both tests to a group of patients and compared the results.
The following data represent results similar to those obtained in the study.
A) Compute the Pearson correlation to measure the degree of relationship between the
two test scores.
B) Is the correlation statistically significant? Use a two-tailed test with a = .01.
C)
What percentage of variance for the cognitive scores is predicted from the 7-Minute
Screen scores?
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution
Trending nowThis is a popular solution!
Step by stepSolved in 3 steps with 3 images
Knowledge Booster
Similar questions
- Using the latest in medical technology, an orthopedic doctor has developed a new surgical procedure that he believes is an improvement over the standard procedure. He wants to study whether the mean recovery time of patients who have the new procedure is less than the mean recovery time of patients who have the standard procedure. The doctor studies a random sample of 11 patients who have the new procedure and a random sample of 9 patients who have the standard procedure. (These samples are chosen independently.) The doctor records each patient's recovery time (in days). The patients who had the new procedure have a sample mean recovery time of 367.3 with a sample variance of 2851.8. The patients who had the standard procedure have a sample mean recovery time of 420.9 with a sample variance of 98.1. Assume that the two populations of recovery times are approximately normally distributed. Can the doctor conclude, at the 0.01 level of significance, that the population mean of the…arrow_forwardIdentifying individuals with a high risk of Alzheimer's disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study. 7-Minute Screen Cognitive Series 3 11 8 19 10 22 8 20 4 14 7 13 4 9 5 20 14 25 Which statistical test would you select: Answer H0: Answer H1: Answer What is the coefficient that indicates the strength of the relationship? Answer =Answer What is the standard error? Answer What is the appropriate 95% CI? [ Answer , Answer ] What is the d-effect size? Answer What is the t-observed? Answer What is the actual p-value? Answer THREE decimal places…arrow_forwardA small pilot study is run to compare a new drug for chronic pain to one that is currently available. Participants are randomly assigned to receive either the new drug or the currently available drug and report improvement in pain on a 5-point ordinal scale: 1=Pain is much worse, 2=Pain is slightly worse, 3= No change, 4=Pain improved slightly, 5=Pain much improved. Is there a significant difference in self-reported improvement in pain? Use the Mann-Whitney U test with a 5% level of significance. Please show work. New Drug: 4 5 3 3 4 2 Standard Drug: 2 3 4 1 2 3arrow_forward
- Identifying individuals with a high risk of Alzheimer’s disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study. Patient 7-Minute Screen Cognitive Series A 3 7 B 7 15 C 4 14 D 5 13 E 7 9 F 5 15 G 11 25 The alternative hypothesis in words and null hypothesis in symbols for a two-tailed test isarrow_forwardIn a study of 301 Hispanic women living in San Antonia, Texas, one variable of interest was the percentage of subjects with impaired fasting glucose (IFG). IFG refers to a metabolic stage intermediate between normal glucose homeostasis and diabetes. In the study, 24 women were classified in the IFG stage. The article cites population estimates for IFG among Hispanic women in Texas as 6.3%. Is there sufficient evidence to indicate the population of Hispanic women in San Antonio has a prevalence of IFG higher than 6.3%? Use 95% confidence level and the p -value method to form your conclusion. Choose the correct null and alternative hypothesis.arrow_forwardIn recent years there has been considerable controversy over the use of standardized testing of high school students. Supporters say that the practice is a good measure of both student progress and teacher performance. Opponents say that too much testing impedes learning and causes unnecessarily large expenses for the school districts. There are even reports that a significant number of high school students opt out of taking some of the standardized tests. In one large city where the school district reported that the average score on a national test taken by students in their junior year was 74, a large group of parents felt that this average was too low. The parents contracted a research company in an attempt to show that the average score was higher than the claimed average of 74. The research company took a random sample of 100 juniors and they collected the corresponding 100 exam scores for those students. - what hypotheses is most appropriate to deal with the problem above. - What…arrow_forward
- Do less agreeable Facebook users tend to spend more time on Facebook? A study (Ivcevic and Ambady, 2013) aimed to investigate various facets of use of the social networking website Facebook. Previous research suggested that individuals with poorer face-to-face social skills may find internet-based social platforms less daunting, so as part of the study Ivcevic and Ambady investigated whether an individual's volume of Facebook use was associated with levels of "agreeableness". The subjects were 99 university students who all had a Facebook page. The subjects agreed to allowing the content of their Facebook pages to be downloaded on six separate occasions over a three-week period. As part of the data gathered on each subject, each of the 99 were individually rated by a selected friend on an "agreeableness" scale (based on average ratings on a questionnaire where all responses were on a Likert scale), with 1 being "low" and 5 "high". We consider here the relationship between "friend…arrow_forwardWhen two independent variables produce effects when combined that would not be present if each independent variables was manipulated in a separate study, we say that there is O no main effect. O only a measured variable an interaction. O a planned comparison. rist and Stangor (2001) studied prejudice and found that you can't predict a person's behavior toward minorities on the basis of whether they are high or lowarrow_forwardResearchers have noted a decline in cognitive functioning as people age (Bartus, 1990). However, the results from other research suggest that the antioxidants in foods such as blueberries may reduce and even reverse these age-related declines (Joseph et al., 1999). To examine this phenomenon, suppose that a researcher obtains a sample of n = 16 adults who are between the ages of 65 and 75. The researcher uses a standardized test to measure cognitive performance for each individual. The participants then begin a 2-month program in which they receive daily doses of a blueberry supplement. At the end of the 2-month period, the researcher again measures cognitive performance for each participant. The results show an average increase in performance of MD = 7.4 with SS = 1215. Does this result support the conclusion that the antioxidant supplement has a significant effect on cognitive performance? Use a two-tailed test with α = .05. Show your computations.arrow_forward
- A team of epidemiologists at the Mayo Clinic wanted to find whether there is an association between obesity and cardiovascular disease (CVD). They conducted a prospective cohort study following obese and non-obese individuals who were free of CVD at the beginning of study for five years. The investigators were also interested in assessing age as a potential confounder, effect modifier, or both. Use the data below to answer the accompanying questions. CVD No CVD Total Obese 10 90 100 Not Obese 35 465 500 Total 45 555 600 CVD No CVD Total Obese 36 164 200 Not Obese 25 175 200 Total 61 339 400 1. Compute the appropriate measure of association for those who were less than age 50. 2. Compute the appropriate measure of association for those who were older or equal to age 50. 3. Compute the crude measure of association? 4. List three attributes that age must satisfy before it could…arrow_forwardIdentifying individuals with a high risk of Alzheimer’s disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study: Patient 7-Minute Screen Cognitive Tests A 3 11 B 8 19 C 10 22 D 8 20 E 4 14 F 7 13 G 4…arrow_forwardIf np is greater than 5 and nq is greater than 5, estimate P(at least 6) with n=13 and p=0.6 by using the normal distribution as an approximation to the binomial distribution; if np <5 or nq<5, then state that the normal approximation is not suitablearrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman
MATLAB: An Introduction with Applications
Statistics
ISBN:9781119256830
Author:Amos Gilat
Publisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...
Statistics
ISBN:9781305251809
Author:Jay L. Devore
Publisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...
Statistics
ISBN:9781305504912
Author:Frederick J Gravetter, Larry B. Wallnau
Publisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...
Statistics
ISBN:9780134683416
Author:Ron Larson, Betsy Farber
Publisher:PEARSON
The Basic Practice of Statistics
Statistics
ISBN:9781319042578
Author:David S. Moore, William I. Notz, Michael A. Fligner
Publisher:W. H. Freeman
Introduction to the Practice of Statistics
Statistics
ISBN:9781319013387
Author:David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:W. H. Freeman