Essentials of Statistics Plus MyLab Statistics with Pearson eText -- Access Card Package (6th Edition) (What's New in Statistics)
6th Edition
ISBN: 9780134858517
Author: Mario F. Triola
Publisher: PEARSON
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Textbook Question
Chapter 6.3, Problem 6BSC
College Presidents There are about 4200 college presidents in the United States, and they have annual incomes with a distribution that is skewed instead of being normal. Many different samples of 40 college presidents are randomly selected, and the
a. What is the approximate shape of the distribution of the sample means (uniform, normal, skewed, other)?
b. What value do the sample means target? That is, what is the mean of all such sample means?
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A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A retail chain is interested in determining whether a digital video point-of-purchase (POP) display would stimulate higher sales for a brand advertised compared to the standard cardboard point-of-purchase display. To test this, a one-shot static group design experiment was conducted over a four-week period in 100 different stores. Fifty stores were randomly assigned to the control treatment (standard display) and the other 50 stores were randomly assigned to the experimental treatment (digital display). Compare the sales of the control group (standard POP) to the experimental group (digital POP).
What were the average sales for the standard POP display (control group)?
What were the sales for the digital display (experimental group)?
What is the (mean) difference in sales between the experimental group and control group?
List the null hypothesis being tested.
Do you reject or retain the null hypothesis based on the results of the independent t-test?
Was the difference between the…
Chapter 6 Solutions
Essentials of Statistics Plus MyLab Statistics with Pearson eText -- Access Card Package (6th Edition) (What's New in Statistics)
Ch. 6.1 - Normal Distribution Whats wrong with the following...Ch. 6.1 - Normal Distribution A normal distribution is...Ch. 6.1 - Standard Normal Distribution Identify the two...Ch. 6.1 - Notation What does the notation z indicate?Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...
Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Significance For bone density scores that are...Ch. 6.1 - Distributions In a continuous uniform...Ch. 6.2 - Birth Weights Based on Data Set 4 Births in...Ch. 6.2 - Birth Weights Based on Data Set 4 Births in...Ch. 6.2 - Normal Distributions What is the difference...Ch. 6.2 - Random Digits Computers are commonly used to...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - Eye Contact In a study of facial behavior, people...Ch. 6.2 - Designing a Work Station A common design...Ch. 6.2 - Jet Ejection Seats The U.S. Air Force once used...Ch. 6.2 - Quarters After 1964, quarters were manufactured so...Ch. 6.2 - Low Birth Weight The University of Maryland...Ch. 6.2 - Body Temperatures Based on the sample results in...Ch. 6.2 - Durations of Pregnancies The lengths of...Ch. 6.2 - Water Taxi Safety When a water taxi sank in...Ch. 6.2 - Curving Test Scores A professor gives a test and...Ch. 6.2 - Outliers For the purposes of constructing modified...Ch. 6.3 - Births There are about 11,000 births each day in...Ch. 6.3 - Sampling with Replacement The Orangetown Medical...Ch. 6.3 - Unbiased Estimators Data Set 4 Births in Appendix...Ch. 6.3 - Sampling Distribution Data Set 4 Births in...Ch. 6.3 - Good Sample? A geneticist is investigating the...Ch. 6.3 - College Presidents There are about 4200 college...Ch. 6.3 - In Exercises 710, use the same population of {4,...Ch. 6.3 - In Exercises 710, use the same population of {4,...Ch. 6.3 - In Exercises 710, use the same population of {4,...Ch. 6.3 - In Exercises 710, use the same population of {4,...Ch. 6.3 - In Exercises 1114, use the population of {34, 36,...Ch. 6.3 - In Exercises 1114, use the population of {34, 36,...Ch. 6.3 - In Exercises 1114, use the population of {34, 36,...Ch. 6.3 - In Exercises 1114, use the population of {34, 36,...Ch. 6.3 - Births: Sampling Distribution of Sample Proportion...Ch. 6.3 - Births: Sampling Distribution of Sample Proportion...Ch. 6.3 - SAT and ACT Tests Because they enable efficient...Ch. 6.3 - Hybridization A hybridization experiment begins...Ch. 6.3 - Using a Formula to Describe a Sampling...Ch. 6.3 - Mean Absolute Deviation Is the mean absolute...Ch. 6.4 - Requirements A researcher collects a simple random...Ch. 6.4 - Small Sample Weights of golden retriever dogs are...Ch. 6.4 - Notation In general, what do the symbols x and x...Ch. 6.4 - Annual Incomes Annual incomes are known to have a...Ch. 6.4 - Using the Central Limit Theorem. In Exercises 58,...Ch. 6.4 - Using the Central Limit Theorem. In Exercises 58,...Ch. 6.4 - Using the Central Limit Theorem. In Exercises 58,...Ch. 6.4 - Using the Central Limit Theorem. In Exercises 58,...Ch. 6.4 - Elevator Safety Example 2 referred to an elevator...Ch. 6.4 - Elevator Safety Exercise 9 uses = 189 lb, which...Ch. 6.4 - Mensa Membership in Mensa requires a score in the...Ch. 6.4 - Designing Manholes According to the website...Ch. 6.4 - Water Taxi Safety Passengers died when a water...Ch. 6.4 - Vending Machines Quarters are now manufactured so...Ch. 6.4 - Southwest Airlines Seats Southwest Airlines...Ch. 6.4 - Coke Cans Assume that cans of Coke are filled so...Ch. 6.4 - Redesign of Ejection Seats When women were finally...Ch. 6.4 - Loading a Tour Boat The Ethan Allen tour boat...Ch. 6.4 - Doorway Height The Boeing 757-200 ER airliner...Ch. 6.4 - Loading Aircraft Before every flight, the pilot...Ch. 6.4 - Correcting for a Finite Population In a study of...Ch. 6.5 - Normal Quantile Plot Data Set 1 Body Data in...Ch. 6.5 - Normal Quantile Plot After constructing a...Ch. 6.5 - Small Sample Data set 29 Coin Weights in Appendix...Ch. 6.5 - Assessing Normality The accompanying histogram is...Ch. 6.5 - Prob. 5BSCCh. 6.5 - Prob. 6BSCCh. 6.5 - Prob. 7BSCCh. 6.5 - Interpreting Normal Quantile Plots. In Exercises...Ch. 6.5 - Prob. 9BSCCh. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Prob. 18BSCCh. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Transformations The heights (in inches) of men...Ch. 6.5 - Lognormal Distribution The following are the...Ch. 6.6 - Continuity Correction In testing the assumption...Ch. 6.6 - Checking Requirements Common tests such as the...Ch. 6.6 - Notation Common tests such as the SAT, ACT, LSAT,...Ch. 6.6 - Distribution of Proportions Each week, Nielsen...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Tennis Replay In the year that this exercise was...Ch. 6.6 - Tennis Replay Repeat the preceding exercise after...Ch. 6.6 - Smartphones Based on an LG smartphone survey,...Ch. 6.6 - Eye Color Based on a study by Dr. P. Sorita at...Ch. 6.6 - Mendelian Genetics When Mendel conducted his...Ch. 6.6 - Sleepwalking Assume that 29.2% of people have...Ch. 6.6 - Voters Lying? In a survey of 1002 people, 701 said...Ch. 6.6 - Cell Phones and Brain Cancer In a study of 420,095...Ch. 6.6 - Births The probability of a baby being born a boy...Ch. 6.6 - Overbooking a Boeing 767-300 A Boeing 767-300...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Notation a. Identify the values of and for the...Ch. 6 - In Exercises 610, assume that women have diastolic...Ch. 6 - In Exercises 610, assume that women have diastolic...Ch. 6 - In Exercises 610, assume that women have diastolic...Ch. 6 - In Exercises 610, assume that women have diastolic...Ch. 6 - In Exercises 610, assume that women have diastolic...Ch. 6 - Bone Density Test A bone mineral density test is...Ch. 6 - Biometric Security In designing a security system...Ch. 6 - Biometric Security Standing eye heights of men are...Ch. 6 - Sampling Distributions Scores on the Gilliam...Ch. 6 - Unbiased Estimators a. What is an unbiased...Ch. 6 - Disney Monorail The Mark VI monorail used at...Ch. 6 - Disney Monorail Consider the same Mark VI monorail...Ch. 6 - Assessing Normality Listed below are the recent...Ch. 6 - Hybridization Experiment In one of Mendels...Ch. 6 - Tall Clubs The social organization Tall Clubs...Ch. 6 - In Exercises 13, use the following recent annual...Ch. 6 - In Exercises 13, use the following recent annual...Ch. 6 - In Exercises 13, use the following recent annual...Ch. 6 - Blue Eyes Assume that 35% of us have blue eyes...Ch. 6 - Foot Lengths of Women Assume that foot lengths of...Ch. 6 - Assessing Normality It is often necessary to...
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