Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Videos
Question
Chapter 12, Problem 44SE
a.
To determine
Determine the information required to decide whether the study is an observational or a controlled experiment.
b .
To determine
Explain why controlled experiments with randomization allow us to draw causality.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Do sports drinks help prevent cramps in endurance sports? At the end of a marathon, officials will ask runners if they drank water or a sports drink during the race, along with whether or not they suffered any cramps. Is this an observational study or experiment?
aswer frq style
Acne is a common skin disease that affects most adolescents and
can continue into adulthood. A study compared the effectiveness
of three acne treatments and a placebo, all in gel form, applied
twice daily for 12 weeks. The study's 517 teenage volunteers
were randomly assigned to one of the four treatments. Success
was assessed as clear or almost clear skin at the end of the 12
week period. The results of the study can be seen in the table
below. Using the appropriate statistical test, determine if there is
significant evidence that the four treatments perform differently.
If so, how do they compare.
Chapter 12 Solutions
Introductory Statistics (2nd Edition)
Ch. 12 - Dairy Products and Muscle The following two...Ch. 12 - Coffee and Depression The following two headlines...Ch. 12 - Prob. 3SECh. 12 - Prob. 4SECh. 12 - Prob. 5SECh. 12 - Prob. 6SECh. 12 - Niacin and Heart Disease The New England Journal...Ch. 12 - Prob. 8SECh. 12 - Prob. 9SECh. 12 - Prob. 10SE
Ch. 12 - Prob. 11SECh. 12 - Prob. 12SECh. 12 - Prob. 13SECh. 12 - Prob. 14SECh. 12 - Prob. 15SECh. 12 - Options on Global Warming People were asked...Ch. 12 - Prob. 17SECh. 12 - SAT Prep and Power Suppose an SAT tutoring company...Ch. 12 - Brain Games (Example 2) Researchers are interested...Ch. 12 - A Smile a Day Smiling is a sign of a good mood,...Ch. 12 - Swimsuits and Racing Speeds (Example 3) New, slick...Ch. 12 - Flu Vaccines and Age Suppose you want to compare...Ch. 12 - Preventing Heart Attacks with Aspirin Suppose that...Ch. 12 - Prob. 24SECh. 12 - Prob. 25SECh. 12 - Prob. 26SECh. 12 - Reading Colored Paper (Example 4) Some people...Ch. 12 - Prob. 28SECh. 12 - Prob. 29SECh. 12 - Prob. 30SECh. 12 - Prob. 31SECh. 12 - Prob. 32SECh. 12 - Prob. 33SECh. 12 - Prob. 34SECh. 12 - Prob. 35SECh. 12 - Prob. 36SECh. 12 - Prob. 37SECh. 12 - Prob. 38SECh. 12 - Prob. 39SECh. 12 - Prob. 40SECh. 12 - Prob. 41SECh. 12 - Prob. 42SECh. 12 - Prob. 43SECh. 12 - Prob. 44SECh. 12 - Prob. 45SECh. 12 - Prob. 46SECh. 12 - Prob. 47SECh. 12 - Prob. 48SECh. 12 - Prob. 49SECh. 12 - Prob. 50SECh. 12 - Alumni Donations The alumni office wishes to...Ch. 12 - Prob. 52SECh. 12 - Drug for Asthma (Example 7) Eosinophils are a form...Ch. 12 - Blood Sugar Refer to Exercise 12.50 on tight...Ch. 12 - Prob. 55SECh. 12 - Prob. 56SECh. 12 - Prob. 57CRECh. 12 - Prob. 58CRECh. 12 - Prob. 59CRECh. 12 - Prob. 60CRE
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 the difference between events and outcomes? Give an example of both using the sample space of tossing a coin 50 times.arrow_forwardResearchers investigate how the presence of cell phones influence the quality of human interaction. Subjects are randomly selected from a population and divided into an experimental group that is asked to leave their phones in the front of the room and a control group that are not asked to leave their cell phones at the front of the room. Subjects are left alone for 10 minutes and then asked to take a survey designed to measure quality of interactions they had with others in the experiment. What statistical test is appropriate?arrow_forwardA medical journal reported on an experiment intended to see if a certain drug could be used as a treatment for the eating disorder anorexia nervosa. The subjects were randomly divided into two groups. Of the 98 who received this drug, 70 were deemed healthy a year later, compared to 50 of the 88 who got the placebo. What is the population for this study? Is this an experimental study? Explain. What is the explanatory variable? What is the response variable? Complete the 2x2 table of counts.arrow_forward
- Which type of experiment is a tightly controlled experiment in which an intervention is given to determine its effect on a certain disease or health condition? Animal study Experimental trial Epidemiological study Case control studyarrow_forwardResearchers have observed that high school students who watched educational television programs as young children tend to have higher grades than their peers who did not watch educational television. Is this an observational study or a controlled experiment? Explain why.arrow_forwardA scientist is studying the effect of a new type of exercise program on cardiovascular health. The scientist randomly assigns individuals to either the exercise program or a control group. The scientist wants to determine if the exercise program has a statistically significant effect on cardiovascular health. The scientist monitors cardiovascular health by measuring the blood pressure of each individual.arrow_forward
- Which statistical test should be used? Researchers wondered if frequent checking of email increases stress. They randomly assigned their participants to check email just three times a day for a week, and then in the second week, to check email as often as they wanted. The researchers did find that participants were less stressed, on average, during the limited email week than during the unlimited email week. Which statistical test should be used? A professor was interested in studying how academic major (Psychology vs. Chemistry) is related to creativity (assessed by a creativity questionnaire). Which statistical test should be used to for a difference between psychology and chemistry majors in creativity?arrow_forwardTexting while driving: The accident rate for students who didn’t text while using a driving simulator was 7%. In a driver distraction study of 1,876 randomly selected students, the accident rate for students who texted while driving was higher than 7%. This difference was statistically significant at the 0.05 level. Which of the following best describes how we should interpret these results? Because of the large size of the sample, these results are strong evidence that texting accounts for a much larger proportion of accidents in the population of student drivers. With a large sample, statistically significant results suggest a large increase in the accident rate for the texting group over the control group. With a large sample, statistically significant results may actually be only a small improvement over the control group (depending on the size of the increase in percentages). Regardless of the sample size, a statistically significant result means there is a meaningful…arrow_forward3arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
College Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
College Algebra (MindTap Course List)
Algebra
ISBN:9781305652231
Author:R. David Gustafson, Jeff Hughes
Publisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt
Introduction to experimental design and analysis of variance (ANOVA); Author: Dr. Bharatendra Rai;https://www.youtube.com/watch?v=vSFo1MwLoxU;License: Standard YouTube License, CC-BY