ALEKS 360 ELEM STATISTICS
10th Edition
ISBN: 9781264241385
Author: Bluman
Publisher: MCG
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Chapter 1.4, Problem 12E
Why do researchers use randomization in statistical studies?
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For each of the time series, construct a line chart of the data and identify the characteristics of the time series (that is, random, stationary, trend, seasonal, or cyclical).
Month Number (Thousands)Dec 1991 65.60Jan 1992 71.60Feb 1992 78.80Mar 1992 111.60Apr 1992 107.60May 1992 115.20Jun 1992 117.80Jul 1992 106.20Aug 1992 109.90Sep 1992 106.00Oct 1992 111.80Nov 1992 84.50Dec 1992 78.60Jan 1993 70.50Feb 1993 74.60Mar 1993 95.50Apr 1993 117.80May 1993 120.90Jun 1993 128.50Jul 1993 115.30Aug 1993 121.80Sep 1993 118.50Oct 1993 123.30Nov 1993 102.30Dec 1993 98.70Jan 1994 76.20Feb 1994 83.50Mar 1994 134.30Apr 1994 137.60May 1994 148.80Jun 1994 136.40Jul 1994 127.80Aug 1994 139.80Sep 1994 130.10Oct 1994 130.60Nov 1994 113.40Dec 1994 98.50Jan 1995 84.50Feb 1995 81.60Mar 1995 103.80Apr 1995 116.90May 1995 130.50Jun 1995 123.40Jul 1995 129.10Aug 1995…
For each of the time series, construct a line chart of the data and identify the characteristics of the time series (that is, random, stationary, trend, seasonal, or cyclical).
Year Month Units1 Nov 42,1611 Dec 44,1862 Jan 42,2272 Feb 45,4222 Mar 54,0752 Apr 50,9262 May 53,5722 Jun 54,9202 Jul 54,4492 Aug 56,0792 Sep 52,1772 Oct 50,0872 Nov 48,5132 Dec 49,2783 Jan 48,1343 Feb 54,8873 Mar 61,0643 Apr 53,3503 May 59,4673 Jun 59,3703 Jul 55,0883 Aug 59,3493 Sep 54,4723 Oct 53,164
High Cholesterol: A group of eight individuals with high cholesterol levels were given a new drug that was designed to lower cholesterol levels. Cholesterol levels, in milligrams per deciliter, were measured before and after treatment for each individual, with the following results:
Individual Before
1
2
3
4
5
6
7
8
237
282
278
297
243
228
298
269
After
200
208
178
212
174
201
189
185
Part: 0/2
Part 1 of 2
(a) Construct a 99.9% confidence interval for the mean reduction in cholesterol level. Let a represent the cholesterol level before treatment minus the cholesterol level after. Use tables to find the critical value and round the answers to at least one decimal place.
Chapter 1 Solutions
ALEKS 360 ELEM STATISTICS
Ch. 1.1 - Read the following on attendance and grades, and...Ch. 1.1 - Define statistics.Ch. 1.1 - What is a variable?Ch. 1.1 - What is meant by a census?Ch. 1.1 - How does a population differ from a sample?Ch. 1.1 - Explain the difference between descriptive and...Ch. 1.1 - Name three areas where probability is used.Ch. 1.1 - Why is information obtained from samples used more...Ch. 1.1 - What is meant by a biased sample?Ch. 1.1 - determine whether descriptive or inferential...
Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.1 - determine whether descriptive or inferential...Ch. 1.2 - Applying the Concepts 1-2 Fatal Transportation...Ch. 1.2 - Explain the difference between qualitative...Ch. 1.2 - Prob. 2ECh. 1.2 - Why are continuous variables rounded when they are...Ch. 1.2 - Name and define the four types of measurement...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are qualitative or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - determine whether the data are discrete or...Ch. 1.2 - give the boundaries of each value. 17. 24 feelCh. 1.2 - give the boundaries of each value. 18. 6.3...Ch. 1.2 - give the boundaries of each value. 19. 143 milesCh. 1.2 - give the boundaries of each value. 20. 19.63 tonsCh. 1.2 - give the boundaries of each value. 21. 200.7 milesCh. 1.2 - give the boundaries of each value. 22. 19 quartsCh. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.2 - classify each as nominal-level, ordinal-level,...Ch. 1.3 - Applying the Concepts 13 American Culture and Drug...Ch. 1.3 - Name five ways that data can be collected.Ch. 1.3 - What is meant by sampling error and nonsampling...Ch. 1.3 - Why are random numbers used in sampling, and how...Ch. 1.3 - Name and define the four basic sampling methods.Ch. 1.3 - For Exercises 510, define a population that may...Ch. 1.3 - For Exercises 510, define a population that may...Ch. 1.3 - For Exercises 510, define a population that may...Ch. 1.3 - For Exercises 510, define a population that may...Ch. 1.3 - For Exercises 510, define a population that may...Ch. 1.3 - For Exercises 5-10, define a population that may...Ch. 1.3 - indentify the sampling method that was used. 11....Ch. 1.3 - indentify the sampling method that was used. 12....Ch. 1.3 - indentify the sampling method that was used. 13....Ch. 1.3 - indentify the sampling method that was used. 14....Ch. 1.3 - indentify the sampling method that was used. 15....Ch. 1.3 - indentify the sampling method that was used. 16....Ch. 1.4 - Todays Cigarettes Vapor or electronic cigarettes...Ch. 1.4 - Explain the difference between an observational...Ch. 1.4 - Prob. 2ECh. 1.4 - List some advantages and disadvantages of an...Ch. 1.4 - List some advantages and disadvantages of an...Ch. 1.4 - What is the difference between an experimental...Ch. 1.4 - What is the difference between independent...Ch. 1.4 - Why are a treatment group and a control group used...Ch. 1.4 - Explain the Hawthorne effect.Ch. 1.4 - What is a confounding variable?Ch. 1.4 - Define the placebo effect in a statistical study.Ch. 1.4 - Prob. 11ECh. 1.4 - Why do researchers use randomization in...Ch. 1.4 - Prob. 13ECh. 1.4 - Prob. 14ECh. 1.4 - determine whether an observational study or an...Ch. 1.4 - determine whether an observational study or an...Ch. 1.4 - determine whether an observational study or an...Ch. 1.4 - determine whether an observational study or an...Ch. 1.4 - identify the independent variable and the...Ch. 1.4 - identify the independent variable and the...Ch. 1.4 - Prob. 21ECh. 1.4 - Prob. 22ECh. 1.4 - Prob. 23ECh. 1.4 - Prob. 24ECh. 1.4 - Prob. 25ECh. 1.4 - suggest some confounding variables that the...Ch. 1.4 - For Exercises 2731, give a reason why the...Ch. 1.4 - Here is the whole truth about back pain.Ch. 1.4 - For Exercises 2731, give a reason why the...Ch. 1.4 - give a reason why the statement made might be...Ch. 1.4 - Prob. 31ECh. 1.4 - List the steps you should perform when conducting...Ch. 1.4 - Prob. 33ECh. 1.4 - Comment on the following statement, taken from a...Ch. 1.4 - In an ad for women, the following statement was...Ch. 1.4 - Prob. 36ECh. 1.4 - Prob. 37ECh. 1.4 - An ad for an exercise product stated: Using this...Ch. 1.4 - Prob. 39ECh. 1.4 - Just l capsule of Brand X can provide 24 hours of...Ch. 1.4 - Male children born to women who smoke during...Ch. 1.4 - Caffeine and Health In the 1980s, a study linked...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - state whether descriptive or inferential...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - Classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each as nominal-level, ordinal-level,...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as qualitative or...Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - classify each variable as discrete or continuous....Ch. 1 - give the boundaries of each value. 35. 56 yards.Ch. 1 - give the boundaries of each value. 36. 105.4...Ch. 1 - give the boundaries of each value. 37. 72.6 tons.Ch. 1 - give the boundaries of each value. 38. 9.54...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - classify each sample as random, systematic,...Ch. 1 - identify each study as being either observational...Ch. 1 - identify each study as being either observational...Ch. 1 - identify each study as being either observational...Ch. 1 - identify each study as being either observational...Ch. 1 - For Exercises 4952, identify the independent and...Ch. 1 - identify the independent and dependent variables...Ch. 1 - identify the independent and dependent variables...Ch. 1 - identify the independent and dependent variables...Ch. 1 - explain why the claims of these studies might be...Ch. 1 - explain why the claims of these studies might be...Ch. 1 - explain why the claims of these studies might be...Ch. 1 - For Exercises 5358, explain why the claims of...Ch. 1 - explain why the claims of these studies might be...Ch. 1 - explain why the claims of these studies might be...Ch. 1 - Determine whether each statement is true or false....Ch. 1 - Determine whether each statement is true or false....Ch. 1 - Prob. 3CQCh. 1 - Prob. 4CQCh. 1 - Prob. 5CQCh. 1 - The height of basketball players is considered a...Ch. 1 - Prob. 7CQCh. 1 - Prob. 8CQCh. 1 - Select the best answer. 9. What are the boundaries...Ch. 1 - Select the best answer. 10. A researcher divided...Ch. 1 - Prob. 11CQCh. 1 - Select the best answer. 12. A study that involves...Ch. 1 - Prob. 13CQCh. 1 - Two major branches of statistics are _____ and...Ch. 1 - Prob. 15CQCh. 1 - The group of all subjects under study is called...Ch. 1 - A group of subjects selected from the group of all...Ch. 1 - Three reasons why samples are used in statistics:...Ch. 1 - The four basic sampling methods are a. ______ b....Ch. 1 - Prob. 20CQCh. 1 - Prob. 21CQCh. 1 - For each statement, decide whether descriptive or...Ch. 1 - Classify each as nominal-level, ordinal-level,...Ch. 1 - Classify each variable as discrete or continuous....Ch. 1 - Give the boundaries of each. a. 32 minutes b. 0.48...
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