Understandable Statistics: Concepts and Methods
12th Edition
ISBN: 9781337119917
Author: Charles Henry Brase, Corrinne Pellillo Brase
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 1.3, Problem 2P
Statistical Literacy Consider a completely randomized experiment in which a control group is given a placebo for congestion relief and a treatment group is given a new drug for congestion relief. Describe a double-blind procedure for this experiment and discuss some benefits of such a procedure.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Explain how methods developed for analyzing randomized experiments can be applied to quasi-experiments?
Calcium and Blood Pressure Does increasing the amount of calcium in our diet reduce blood
pressure? Examination of a large sample of people revealed a relationship between calcium intake
and blood pressure. Such observational studies do not establish causation. Researchers therefore
designed a randomized comparative experiment.
The subjects were 21 healthy men who volunteered to take part in the experiment. They were
randomly assigned to two groups: 10 of the men received a calcium supplement for 12 weeks,
while the control group of 11 men received a placebo pill that looked identical. The experiment
was double-blind. The response variable is the decrease in systolic (top number) blood pressure
for a subject after 12 weeks, in millimeters of mercury. An increase appears as a negative number.
Do the data provide convincing evidence that a calcium supplement reduces blood pressure more
than a placebo, on average, for subjects like the ones in this study?
Group 1 (calcium)
Group (placebo)…
I don't understand the whole concept of randomized experiments.
What does it mean if the cases are not selected randomly but are assigned randomly to groups?
How to determine causality?
When do we generalize to the whole population?
Chapter 1 Solutions
Understandable Statistics: Concepts and Methods
Ch. 1.1 - Statistical Literacy In a statistical study what...Ch. 1.1 - Statistical Literacy Are data at the nominal level...Ch. 1.1 - Statistical Literacy What is the difference...Ch. 1.1 - Statistical Literacy For a set population, does a...Ch. 1.1 - Critical Thinking Numbers are often assigned to...Ch. 1.1 - Interpretation Lucy conducted a survey asking some...Ch. 1.1 - Marketing: Fast Food A national survey asked 1261...Ch. 1.1 - Advertising: Auto Mileage What is the average...Ch. 1.1 - Ecology: Wetlands Government agencies carefully...Ch. 1.1 - Archaeology: Ireland The archaeological site of...
Ch. 1.1 - Student Life: Levels of Measurement Categorize...Ch. 1.1 - Business: Levels of Measurement Categorize these...Ch. 1.1 - Fishing: Levels of Measurement Categorize these...Ch. 1.1 - Education: Teacher Evaluation If you were going to...Ch. 1.1 - Critical Thinking You are interested in the...Ch. 1.2 - Statistical Literacy Explain the difference...Ch. 1.2 - Statistical Literacy Explain the difference...Ch. 1.2 - Statistical Literacy Marcie conducted a study of...Ch. 1.2 - Statistical Literacy A random sample of students...Ch. 1.2 - Interpretation In a random sample of 50 students...Ch. 1.2 - Interpretation A campus performance series...Ch. 1.2 - Critical Thinking Greg took a random sample of...Ch. 1.2 - Critical Thinking Consider the students in your...Ch. 1.2 - Critical Thinking Suppose you are assigned the...Ch. 1.2 - Critical Thinking In each of the following...Ch. 1.2 - Sampling: Random Use a random-number table to...Ch. 1.2 - Prob. 12PCh. 1.2 - Sampling: Random Use a random-number table to...Ch. 1.2 - Prob. 14PCh. 1.2 - Computer Simulation: Roll of a Die A die is a cube...Ch. 1.2 - Education: Test Construction Professor Gill is...Ch. 1.2 - Education: Test Construction Professor Gill uses...Ch. 1.2 - Sampling Methods: Benefits Package An important...Ch. 1.2 - Sampling Methods: Health Care Modern Managed...Ch. 1.3 - Statistical Literacy A study of college graduates...Ch. 1.3 - Statistical Literacy Consider a completely...Ch. 1.3 - Critical Thinking A brief survey regarding...Ch. 1.3 - Critical Thinking A randomized block design was...Ch. 1.3 - Interpretation Zane is examining two studies...Ch. 1.3 - Interpretation Suppose you are looking at the 2006...Ch. 1.3 - Ecology: Gathering Data Which technique for...Ch. 1.3 - General: Gathering Data Which technique for...Ch. 1.3 - General: Completely Randomized Experiment How...Ch. 1.3 - Surveys: Manipulation The New York Times did a...Ch. 1.3 - Critical Thinking An agricultural study is...Ch. 1 - Critical Thinking Sudoku is a puzzle consisting of...Ch. 1 - Prob. 2CRPCh. 1 - Statistical Literacy You are conducting a study of...Ch. 1 - Prob. 4CRPCh. 1 - Prob. 5CRPCh. 1 - General: Type of Sampling Categorize the type of...Ch. 1 - Prob. 7CRPCh. 1 - General: Experiment How would you use a completely...Ch. 1 - Prob. 11CRPCh. 1 - Prob. 2DHCh. 1 - Prob. 1LCCh. 1 - Discuss each of the following topics in class or...Ch. 1 - Prob. 1UTCh. 1 - Prob. 2UT
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
- What is an experiment? Give two examples.arrow_forwardWhat is meant by the sample space of an experiment?arrow_forwardA data collection method is described to investigate a difference in means. Determine which data analysis method is more appropriate: paired data difference in means or difference in means with two separate groups. To study the effect of women's tears on men, levels of testosterone are measured in 50 men after they sniff women's tears and after they sniff a salt solution. The order of the two treatments was randomized and the study was double-blind. O Paired data difference in means O Difference in means with two separate groupsarrow_forward
- Until 2002, hormone replacement therapy (HRT), estrogen and/or progesterone, was commonly prescribed to post-menopausal women. This changed in 2002, when the results of a large clinical trial were published 7500 women were randomized to take HRT, 7100 were randomized to placebo. 170 HRT and 130 placebo women developed invasive breast cancer. Does HRT increase risk of breast cancer? Conduct hypothesis test. Hint: Use randomization distribution to answer the question.arrow_forwardA study investigates how leisure walking affects individuals' attitudes to the pandemic. A scale, Cognitive-Affective Maps (CAM), is used to measure individual's cognitive and affective attitudes toward the corona pandemic and related issues. The values of CAM between two groups of individuals after they a leisure walk and any self-chosen activity at home, are compared. A sample of 200 subjects is considered. Describe a randomized experimental study is conducted to collect the data for the study. State how to analyses the effects of a leisure walk on cognitive and affective attitudes.arrow_forwardMm2arrow_forward
- Based on the results presented, did the exercise intervention groups still receive a health benefit even if significant weight loss did not occur? Explain.arrow_forwardA researcher studied iron-deficiency anemia in women in each of two developing countries. Differences in the dietary habits between the two countries led the researcher to believe that anemia is less prevalent among women in the first country than among women in the second country. A random sample of 1900 women from the first country yielded 441 women with anemia, and an independently chosen, random sample of 1800 women from the second country yielded 461 women with anemia. Based on the study can we conclude, at the 0.01 level of significance, that the proportion p₁ of women with anemia in the first country is less than the proportion P₂ of women with anemia in the second country? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified in the parts below. (If necessary, consult a list of formulas.) (a) State the null hypothesis H. and the alternative hypothesis H₁. H₁ :0 H₁ :0 (b)…arrow_forwardAn investigator wants to perform an experimental study on the effectiveness of a new therapy (Therapy A), compared to the current therapy (Therapy B) for breast cancer to prevent metastases. The study sample is 500 female patients aged 18 years or older who are patients with a diagnosis of breast cancer of several clinics and hospitals in Los Angeles County. Which of the following treatment assignment schemes can be used so that the study is properly called a randomized controlled trial? (choose one best answer) The 1st eligible patient will be assigned to one therapy by flipping a coin and all the following patients will be assigned alternatively to the two therapies so that no two consecutive patients will receive the same therapy. Any assignment scheme that makes it impossible to predict what is the therapy that the next patient will receive. Any assignment scheme which guarantees exactly 200 patients assigned to each study group. Any eligible patient admitted on an even-numbered…arrow_forward
- A researcher studied iron-deficiency anemia in women in each of two developing countries. Differences in the dietary habits between the two countries led the researcher to believe that anemia is less prevalent among women in the first country than among women in the second country. A random sample of 2000 women from the first country yielded 488 women with anemia, and an independently chosen, random sample of 1700 women from the second country yielded 437 women with anemia. Based on the study can we conclude, at the 0.05 level of significance, that the proportion P₁ of women with anemia in the first country is less than the proportion p₂ of women with anemia in the second country? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified in the parts below. (If necessary, consult a list of formulas.) (a) State the null hypothesis Ho and the alternative hypothesis H₁. HO P X S Ho :O…arrow_forwardTwo types of artificial knee are to be compared for range of motion, measured in degrees. Theoretically, either could give a greater range. A journal article on the first type of knee gave a sample mean of 112 degrees, with a standard deviation of 13 degrees, and an article on the second type gave a sample mean of 118 degrees with a standard deviation of 11 degrees. We want to perform a new randomized trial to decide whether a 6 degree difference is statis-tically detectable using a 5% significance level, and maintaining at least 90% power. We are willing to assume that the population standard deviation is somewhere between the sample standard deviations reported in the two articles. What is the minimum number of subjects receiving each type of knee (in a balanced design) we must record? Hint: Your answer should be a number, representing the number of subjects receiving a Type 1 knee (which will be equal to the number receiving a Type 2 knee).arrow_forwardA clinical trial is run among 40 HIV patients in order to assess the effectiveness of a new anti-retroviral therapy. Patients are randomized. One group received the standard anti-retroviral therapy (usual care) while the other group received the new anti-retroviral therapy. They are monitored for three months. The primary variable is the viral load which represents the number of HIV copies per milliliter of blood. The most appropriate statistical test to determine the significant difference in viral load in patients receiving the standard versus the new anti-retroviral therapy is Mann- Whitney U Test. a.True b.Falsearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGALCollege Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
College Algebra (MindTap Course List)
Algebra
ISBN:9781305652231
Author:R. David Gustafson, Jeff Hughes
Publisher:Cengage Learning
what is Research Design, Research Design Types, and Research Design Methods; Author: Educational Hub;https://www.youtube.com/watch?v=LpmGSioXxdo;License: Standard YouTube License, CC-BY