MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Related questions
Topic Video
Question
Study 3: Two hundred people were randomly selected from a list of all people living in Minneapolis who receive Social Security. Each person was asked to participate in a statistical study, and all agreed to participate. Those who had no previous history of heart problems were instructed to take calcium supplements. Those with a previous history of heart problems were instructed not to take calcium supplements. The participants were followed for 5 years, and whether or not they had a heart attack during the 5-year period was noted. The researchers found that the proportion of heart attack victims in the calcium supplement group was significantly higher than the proportion of heart attack victims in the no supplement group.
A) observational study or an experiment
B) Did the study use random selection from some population? (Yes or No)
C) Did the study use random assignment to the experimental groups? (Yes or No)
D) Based on the description of the study, is it reasonable to conclude that taking calcium supplements if the cause of the increased risk of a heart attack? (Yes or No)
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 2 steps
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- A health statistics agency in a certain country tracks the number of adults who have health insurance. Suppose according to the agency, the uninsured rates in a recent year are as follows: 5.2% of those under the age of 18, 12.9% of those ages 18-64, and 1.3% of those 65 and older do not have health insurance. Suppose 22.4% of people in the county are under age 18, and 62.3% are ages 18-64. (a) What is the probability that a randomly selected person in this country is 65 or older? 15.3 (b) Given that a person in this country is uninsured, what is the probability that the person is 65 or older? (Round your answer to three decimal places.) 0.023 Xarrow_forwardAre birthdays "evenly distributed" throughout the year, or are they more common during some parts of the year than others? Owners of a children's toy store chain asked this question. Some data collected by the chain are summarized in the table below. The data were obtained from a random sample of 180 people. The birthdate of each person was recorded, and each of these dates was placed into one of four categories: winter (December 21-March 20), spring (March 21-June 20), summer (June 21-September 20), and fall (September 21-December 20). The numbers in the first row of the table are the frequencies observed in the sample for these season categories. The numbers in the second row are the expected frequencies under the assumption that birthdays are equally likely during each season of the year. The bottom row of numbers gives the following value for each of the season categories. (Each expert I have asked has gotten the critical value wrong so I added a picture of the correct formula to…arrow_forwardYou are a sales manager for a grocery store, and you want to see if the introduction of a new sales promotion will increase the sales in your store. To do so, you decided to create an experiment by giving a small sample of customers the promotion before expanding it to a larger customer base. You gave 18 people the promotion, and also observed the sales of 27 people who did not get the promotion as a control group. You found those who received the promotion to have an average monthly sales of $456.60, with a sample standard deviation of $52.23. You found those who did not receive the promotion had an average monthly sales of $361.46, with a sample standard deviation of $56.11. Suppose you want to use hypothesis testing (two-sample test) to investigate if the promotion has increased the sales of your store. Using the order promotion no promotion in your hypothesis test, what is the value of the test statistic for your analysis? Note: 1- Only round your final answer. Round your final…arrow_forward
- A. Headache Pain : There are many over-the-counter pain relievers. By the end of the semester, you have a tremendous headache and are looking for the most effective pain relief available. You conduct a study comparing the three most popular pain relievers and a placebo to see which work best. You use only subjects with headaches and record the amount of time (in minutes) it takes for their headache to go away after they receive the medication. You randomly assign 60 participants to one of the four conditions using a double- + blind procedure. (Use a = Placebo 70 Drug A 30 Drug B 10 Drug C 10 30 60 40 20 50 40 10 10 60 30 40 10 10 40 30 30 30 30 30 10 40 20 20 20 60 40 20 30 50 30 30 10 30 30 20 20 60 20 10 10 20 40 20 30 20 50 20 10 40 20 30 30 State the hypotheses Critical value and df Test statisticarrow_forwardA. Headache Pain : There are many over-the-counter pain relievers. By the end of the semester, you have a tremendous headache and are looking for the most effective pain relief available. You conduct a study comparing the three most popular pain relievers and a placebo to see which work best. You use only subjects with headaches and record the amount of time (in minutes) it takes for their headache to go away after they receive the medication. You randomly assign 60 participants to one of the four conditions using a double- blind procedure. (Use a = .05) Drug A Drug C 10 Placebo Drug B 10 70 30 30 60 40 20 50 40 10 10 60 30 10 10 40 40 30 30 30 30 30 10 40 20 20 20 60 40 20 30 50 30 30 10 30 30 20 20 60 20 10 10 20 40 30 20 50 20 20 10 40 20 30 30 IV (or predictor) variable DV (or criterion) variable What type of analysis should you conduct to determine which method relieves headache pain most swiftly?arrow_forwardAre birthdays "evenly distributed" throughout the year, or are they more common during some parts of the year than others? Owners of a children's toy store chain asked this question. Some data collected by the chain are summarized in the table below. The data were obtained from a random sample of 180 people. The birthdate of each person was recorded, and each of these dates was placed into one of four categories: winter (December 21-March 20), spring (March 21-June 20), summer (June 21-September 20), and fall (September 21-December 20). The numbers in the first row of the table are the frequencies observed in the sample for these season categories. The numbers in the second row are the expected frequencies under the assumption that birthdays are equally likely during each season of the year. The bottom row of numbers gives the following value for each of the season categories. (Each expert I have asked has gotten the critical value wrong so I added a picture of the correct formula to…arrow_forward
- A researcher is conducting an experimental study on the effect of aspirin on heart attack risk. In order to assign who will receive aspirin and who will receive a placebo, she first divides her study into three age groups (18-29, 30-49, and 50 or older). She then randomly assigns individuals within these age groups to either receive aspirin or the placebo. This is an example of a cluster ?arrow_forwardWhen an audit must be conducted that involves a tedious examination of a large inventory, the audit may be very costly and time consuming if each item in the inventory must be examined. In such situations, the auditor frequently obtains a random sample of items from the complete inventory and uses the results of an audit of the sampled items to check the validity of the company's financial statement. A large company’s financial statement claims an inventory that averages $600 per item. The following data are the auditor’s assessment of a random sample of 75 items from the company’s inventory. The values resulting from the audit are rounded to the nearest dollar. Estimate the mean value of an item in the inventory using a 95% confidence interval. Is there substantial evidence (a 5 .01) that the mean value of an item in the inventory is less than $600? What is the target population for the above inferences? Would normal distribution–based procedures be appropriate for answering the…arrow_forwardIn a current study, a random sample of 20 teachers from Georgia and an independent random sample of 20 teachers from Indiana have been asked to report their annual income. The data obtained are as follows. Georgia 33567, 41744, 51186, 30464, 51606, 42617, 48830, 41455, 49371, 40828, 44007, 42605, 34923, 30519, 42581, 52952, 45651, 45084, 35455, 27800 Send data to calculator Indiana Annual income in dollars 29227, 35464, 45458, 32113, 29125, 38494, 23709, 32874, 34046, 21221, 39527, 56140, 38977, 47806, 44866, 36325, 34654, 38647, 37073, 36344 Send data to Excel The population standard deviations for the annual incomes of teachers in Georgia and in Indiana are estimated as $6500 and $6350, respectively. It is also known that both populations are approximately normally distributed. Construct a 90% confidence interval for the difference between the mean annual income of teachers from Georgia (,) and the mean annual income of teachers from Indiana (₂). Then find the lower limit and upper…arrow_forward
- Suppose an investigator has studied the possible association between the use of a weight-loss drug and a rare central nervous system (CNS) disorder. He samples from a group of volunteers with and without the disorder, and records whether they have used the weight-loss drug. The data are summarized in the attached table: What is the estimated the odds ratio for the presence of a CNS disorder, comparing people who have used the weight-loss drug to those who have not? What test would you use to evaluate the null hypothesis of no association between weight-loss drug use and presence of a CNS disorder?arrow_forwardA pharmaceutical company is testing the effectiveness of its vaccine across two different age brackets. They take a sample and split the participants up into two separate groups. Group A consists of 44 people who are between ages 13 and 18. Group B consists of 58 people between ages 19 and 26. After being administered the vaccine, it was found that 37 people from group A were immune to the virus and 42 people from group B were immune. What proportion of people from Group A were immune? What proportion of people from Group B were immune? What proportion of people in this study were immune?arrow_forwardA breeder of golden retriever dogs has kept records on litter size for several years. They want to know if litter size is dependent on parent age. Age of Sire 9.0 7.0 6.5 4.3 5.0 4.1 3.7 8.0 7.0 4.1 4.5 7.0 6.0 Age of Dam 2.0 2.5 4.0 3.3 6.0 5.0 4.5 4.1 8.2 2.4 2.9 3.7 4.0 Litter Size 11 10 9 12 5 9 9 8 7 10 12 10 9 b. Perform a regression analysis. Define your hypothesis, state your conclusions, and show all work.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage Learning
Statistics 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:PEARSON
The Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. Freeman
Introduction 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