Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Chapter 1, Problem 62CRE
Brief Exercise and Diabetes As part of a study, sixteen young men performed high-intensity exercise that totaled only 15 minute in two-week period. At the end of two weeks, several (but not all) tests for diabetes, such as an insulin sensitivity test, showed improvement. Do these results indicate that brief, high-intensity exercise causes an improvement in markers for diabetes? What essential component of both controlled experiments and observational studies is missing from this study?
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Researchers Regine Dilla and associates wanted to determine whether consumption of cola is associated with lower bone mineral density. They looked at 1125 men and 1413 women in the Framingham Osteoporosis Study, which is a cohort that began in 1971. The first examination in this study began between 1971 and 1975, with participants returning for an examination every 4 years. Based on results of questionnaires, the researchers were able to determine cola consumption on a weekly basis. Analysis of the results indicated that women who consumed at least one cola per day (on average) had a bone mineral density that was significantly lower at the femoral neck than those who consumed less than one cola per day. The researchers did not find this relation in men.
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Studies have suggested that alcohol abuse and disorders are found to be more prevalent during early adulthood than in any other age group, with about 9% of young adults (age 18 to 29 years) meeting the criteria to be labeled as alcoholic. In addition, surveys have shown that college students tend to drink more than their peers who do not attend college.
You want to test to see if there are differences in excessive alcohol use in young adults that attend college versus those who do not, so you surveyed 405 young adults, age 19 to 22, about their alcohol use by asking the question, "Have you consumed alcohol to the point of intoxication at least once within the past month?" with the following results.
Young Adults Attending College
Young Adults Not Attending College
n1 = 255
n2 = 150
y1 = 96
said "yes"
y2 = 44
said "yes"
p̂1 =
96
255
p̂2 =
44
150
(a)
Calculate the test statistic. (Round your answer to two decimal places.)
(b)
If
H0:…
Research indicates that there may be a relationship between caffeinated coffee consumption and risk of depression in women. Provided is data on the amount of caffeinated coffee consumed and whether the woman was diagnosed with clinical depression. Of interest is to see if there is evidence of an association between caffeinated coffee intake and clinical depression in women. What are the hypotheses?
Caffeinated coffee
Depression
<1 cup/wk
>=1 cup/day
2-3 cups/day
4+ cups/day
Total
Yes
670
1278
564
95
2607
No
11545
22573
11726
2288
48132
Total
12215
23851
12290
2383
50739
A. H0: H0 is not true and there is no association between caffeine intake and depression in women
B. There is no association between caffeine intake and depression in women and H0 is not true
C. Research indicates that there may be a relationship between caffeinated coffee consumption and risk of depression in women
D. H0: There is an association between caffeine intake and…
Chapter 1 Solutions
Introductory Statistics (2nd Edition)
Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...
Ch. 1 - SECTION EXERCISES Brain Size (Example 2) In 1991,...Ch. 1 - SECTION EXERCISES Students’ Ages The accompanying...Ch. 1 - Snacks Emmanuel, a student at a Los Angeles high...Ch. 1 - Movies A sample of students were questioned to...Ch. 1 - SECTION EXERCISES Older Siblings (Example 3) At a...Ch. 1 - SECTION EXERCISES College Students working at a...Ch. 1 - Finding and Using Percentages a. A statistics...Ch. 1 - Finding and Using Percentages a. A hospital...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES The data in the Table 1A were...Ch. 1 - SECTION EXERCISES Two-Way Table from Data The...Ch. 1 - SECTION EXERCISES Two-way Table from Data Make a...Ch. 1 - SECTION EXERCISES Population Prediction The 2009...Ch. 1 - SECTION EXERCISES 2007 Population The 2009 World...Ch. 1 - Living with AIDS The table gives the number of...Ch. 1 - Population Density The accompanying table gives...Ch. 1 - Marriage rates the number of married people in the...Ch. 1 - Births and Deaths the following information about...Ch. 1 - Course Enrollment Rates (Example 5 ) two sections...Ch. 1 - Pedestrian fatalities In 2008, the National...Ch. 1 - Prob. 31SECh. 1 - Records of patients who have had broken ankles are...Ch. 1 - For Exercises 1.39 through 1.44, indicate whether...Ch. 1 - For Exercises 1.39 through 1.44, indicate whether...Ch. 1 - For Exercises 1.39 through 1.44, indicate whether...Ch. 1 - For Exercises 1.39 through 1.44, indicate whether...Ch. 1 - A researcher was interested in the effect of...Ch. 1 - A researcher was interested in the effect of...Ch. 1 - Effects of Tutoring on Math Grades (Example 8) A...Ch. 1 - Treating Depression A doctor who believes strongly...Ch. 1 - Early Tonsillectomy for Children (Example 6 )...Ch. 1 - Pneumonia Vaccine for Young Children A study...Ch. 1 - Copper Bracelets (Example 7 ) Some people believe...Ch. 1 - Weight Loss Study A group of overweight people are...Ch. 1 - Do Pesticides Cause Parkinson's Disease? A study...Ch. 1 - Breast Cancer Two drugs were tested to see whether...Ch. 1 - Flu Vaccine In the fall of 2004, there was a...Ch. 1 - Effect of Confederates on Compliance A study was...Ch. 1 - Vitamin C and Allergies (Example 8 ) Posted at the...Ch. 1 - Does Overeating Reduce Brain Function? The Harvard...Ch. 1 - Effects of Light Exposure (Example 9) A study...Ch. 1 - Scared Straight The idea of sending delinquents to...Ch. 1 - Obesity and Marital Status A 2009 study analyzed...Ch. 1 - Prob. 54CRECh. 1 - Probation a statistics student conducted a study...Ch. 1 - Scorpion Antivenom A study was done on children (6...Ch. 1 - Writing: Vitamin D Describe the design of a...Ch. 1 - Writing: Strokes People who have had strokes are...Ch. 1 - Medicaid Expansion Medicaid is a program...Ch. 1 - HIV-1 and HIV-2 Does infection with HIV-2 slow the...Ch. 1 - Death Row and Head Trauma A study conducted by...Ch. 1 - Brief Exercise and Diabetes As part of a study,...
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