Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Chapter 1, Problem 46SE
Breast Cancer Two drugs were tested to see whether they helped women who had breast cancer without lymph node involvement. The drugs are called TAC (docetaxel, doxorubicin, and cyclophosphamide) and FAC (fluorouracil, doxorubicin, and cyclophosphamide). About half of the 1060 women with breast cancer without lymph node involvement were randomly assigned to TAC, and the other half were assigned to FAC. After 77 months, 4473 out of 539 of the women assigned to TAC were alive, and 426 out of 521 women assigned to FAC were alive.
a. Find both sample percentages of survival, and compare them descriptively.
b. Was this a controlled experiment or an observational study? Explain why. From studies like these, can we conclude a cause-and-effect relationship between the drug type and the survival percentage? Why or why not?
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A common way for two people to settle a frivolous dispute is to play a game of rock-paper-scissors. In this game, each person simultaneously displays a hand signal to indicate a rock, a piece of paper, or a pair of scissors. Rock beats scissors, scissors beats paper, and paper beats rock. If both players select the same hand signal, the game results in a tie.
Two roommates, roommate A and roommate B, are expecting company and are arguing over who should have to wash the dishes before the company arrives. Roommate A suggests a game of rock-paper-scissors to settle the dispute.
Consider the game of rock-paper-scissors to be an experiment. In the long run, roommate A chooses rock 21% of the time, and roommate B chooses rock 61% of the time; roommate A selects paper 39% of the time, and roommate B selects paper 21% of the time; roommate A chooses scissors 40% of the time, and roommate B chooses scissors 18% of the time. (These choices are made randomly and independently of each…
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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