Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Chapter 10, Problem 38SE
Is Smiling Independent of Age? Randomly chosen people were observed for about 10 seconds in several public places, such as malls and restaurants, to see whether they smiled during that time. The table shows the results for different age groups.
(Source: M. S. Chapell, Frequency of Public Smiling over the Life Span, Perceptual and Motor Skills 85[1997]: 1326.)
a. Find the percentage of each age group that were observed smiling, and compare these percentages.
b. Treat this as a single random sample of people, and test whether smiling and age group are associated, using a significance level of
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Chapter 10 Solutions
Introductory Statistics (2nd Edition)
Ch. 10 - Tests a. In Chapter 8, you learned some tests of...Ch. 10 - In Chapter 9, you learned some tests of means. Are...Ch. 10 - Crime and Gender A statistics student conducted a...Ch. 10 - Red Cars and Stop Signs The table shows the raw...Ch. 10 - The table summarizes the outcomes of a study that...Ch. 10 - Finger Length There is a theory that relative...Ch. 10 - Prob. 7SECh. 10 - Prob. 8SECh. 10 - Effects of Television Violence on Men (Example 1)...Ch. 10 - Prob. 10SE
Ch. 10 - Mummies with Heart Disease According to the...Ch. 10 - Prob. 12SECh. 10 - Violins Stradivarius violins, made in the 1700s by...Ch. 10 - Coin Flips You flip a coin 100 times and get 58...Ch. 10 - Prob. 15SECh. 10 - Prob. 16SECh. 10 - Prob. 17SECh. 10 - Prob. 18SECh. 10 - Are Humans Like Random Number Generators? (Example...Ch. 10 - Is the Random Number Table Really Random? We...Ch. 10 - Coin Spins A penny was spun on a hard, flat...Ch. 10 - Prob. 22SECh. 10 - Is the Six-Sided Die Fair? The table shows the...Ch. 10 - Is the Six-Sided Die Fair? Repeat the chi-square...Ch. 10 - Violins Professional musicians listened to five...Ch. 10 - Mummies with Heart Disease Exercise 10.11 on...Ch. 10 - Party and Right Direction (Example 4) Suppose a...Ch. 10 - Antibiotic or Placebo A large number of surgery...Ch. 10 - Prob. 29SECh. 10 - Prob. 30SECh. 10 - Prob. 31SECh. 10 - Unemployment Rates U.S. Unemployment rates for all...Ch. 10 - Prob. 33SECh. 10 - Weight Loss Overweight or obese adults from...Ch. 10 - Prob. 35SECh. 10 - Prob. 36SECh. 10 - Gender and Happiness of Marriage The table shows...Ch. 10 - Is Smiling Independent of Age? Randomly chosen...Ch. 10 - Preschool Attendance and High School Graduation...Ch. 10 - Preschool Attendance and High School Graduation...Ch. 10 - Preschool Attendance and High School Graduation...Ch. 10 - Prob. 42SECh. 10 - Prob. 43SECh. 10 - Antiretrovirals to Prevent HIV A study conducted...Ch. 10 - Confederates and Compliance A study was done to...Ch. 10 - Endocarditis Kang et al. reported on a randomized...Ch. 10 - Prob. 47SECh. 10 - Prob. 48SECh. 10 - Prob. 49SECh. 10 - Night Shifts A random sample of nurses working...Ch. 10 - Gender and Political Party Affiliation The data in...Ch. 10 - Children and Happiness The data in the table come...Ch. 10 - Prob. 53SECh. 10 - Nice Rats Rats had a choice of freeing another rat...Ch. 10 - Young Criminals and Violence A statistics student...Ch. 10 - Egg Allergy in Children In a randomized,...Ch. 10 - Suppose you have a random sample of students...Ch. 10 - In exercises 10.57 to 10.64, choose an appropriate...Ch. 10 - Suppose you take a survey of random students at a...Ch. 10 - Prob. 60CRECh. 10 - Prob. 61CRECh. 10 - In exercises 10.57 to 10.64, choose an appropriate...Ch. 10 - Prob. 63CRECh. 10 - In exercises 10.57 to 10.64, choose an appropriate...Ch. 10 - Perry Preschool Arrests The Perry Preschool...Ch. 10 - Parental Training and Criminal Behavior of...Ch. 10 - Prob. 67CRECh. 10 - Prob. 68CRECh. 10 - Prob. 69CRECh. 10 - Prob. 70CRECh. 10 - Robot Cockroaches Cockroaches tend to rest in...Ch. 10 - Robot Cockroaches Refer to the description in...Ch. 10 - Prob. 73CRECh. 10 - Conviction Rate with Opposite Race Here are the...
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