Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Textbook Question
Chapter 1, Problem 38SE
A researcher was interested in the effect of exercise on memory .She randomly assigned half of a group of students to run up a stairway three times and the other half to rest for an equivalent amount of time. Each student was then asked to memorize a series of random digits. She compared the numbers of digits remembered for the two groups.
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Walter is a sales manager for a chain of car dealerships. He encourages the managers at each store to
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10
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1
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An educational psychologist is interested in whether using a child’s own name in a story affected attention span while reading. Six children were randomly assigned to read a story under ordinary conditions (using common and generic names). Five other children read versions of the same story, but with each child’s ownname substituted for one of the children in the story. The researcher measured the amount of time (in minutes) each child spent reading the story. The results are shown in the following table. Does including the child’s namemake any difference in attention span?
Test the hypothesis at an alpha set to .05, following these steps: a) write the null and alternative hypotheses; b) determine the critical value(s); c) draw the comparison distribution with rejection region(s) shaded; d)use the correct formula to compute the test statistic; e) state the statistical decision; f) state a brief conclusion.
Use the following information for the question. A group of home gardeners want to test whether the type of
soil used to grow heirloom tomatoes has an effect on the number of tomatoes harvested. Gardeners
randomly assigned tomato plants to be grown in soil with no fertilizer, commercial plant food, and homemade
compost. All other growing conditions were kept the same. Forty plants were assigned to each group. At the
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One-way ANOVA
F=0.762135
P=0.5202354
Factor
df-2
SS=710.349206
MS=355.174603
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correct conclusion.
O Reject Ho. We can conclude that the treatment of the soil affects the number of heirloom tomatoes harvested.
O Reject Ho- We can…
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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