statistical thinking in the process of data collection
To demonstrate your knowledge of using statistical thinking in the process of data collection, complete the problems from Chapter 1 listed below.
• Section 1.1 – numbers 22, 24, 32, 34, 52, 58
• Section 1.2 – numbers 14, 16
• Section 1.5 – numbers 14, 16, 18, 20
• Section 1.6 – numbers 12, 14 (complete a-f only)
Please label each problem and be sure to include your name in the document.
To demonstrate your knowledge of using statistical thinking in the process of data collection, complete the problems from Chapter 1 listed below.
• Section 1.1 – numbers 22, 24, 32, 34, 52, 58
-In Problems 22, classify the variable as qualitative or quantitative.
22.Student ID number
In Problems 24, determine whether the quantitative variable is discrete or continuous.
24.Volume of water lost each day through a leaky faucet
-In Problems 32,34, determine the level of measurement of each variable.
32.Movie ratings of one star through five stars
34.Year of birth of college students
52.Retirement Planning The Principal Financial Group conducted a survey of 1172 employees in the United States between July 28, 2010, and August 8, 2010, and asked if they were currently participating in the employer-sponsored automatic payroll deduction for a 401(k) plan to save for retirement. Of the 1172 employees surveyed, 27% indicated they were participating. The Principal Group reported that 27% of all employees in the United States participate in automatic payroll deduction for a 401(k) plan to save for retirement with a 4% margin of error and 95% confidence.
• (a)What is the research objective?
• (b)What is the population?
• (c)What is the sample?
• (d)List the descriptive statistics.
• (e)What can be inferred from this survey?
• (a)The winning ticket number.
• (b)The winning ticket number was announced as 329. An attendee noted his ticket number was 294 and stated, “I guess I arrived too early.”
• (c)The winning ticket number was announced as 329. An attendee looked around the room and commented, “It doesn’t look like there are 329 people in attendance.”
58. In your own words, define the four levels of measurement of a variable. Give an example of each.
• Section 1.2 – numbers 14, 16
14. While shopping, 200 people are asked to perform a taste test in which they drink from two randomly placed, unmarked cups. They are then asked which drink they prefer.
16.Conservation agents netted 250 large-mouth bass in a lake and determined how many were carrying parasites.
• Section 1.5 – numbers 14, 16, 18, 20
In Problems 14, 16, the survey has bias. (a) Determine the type of bias. (b) Suggest a remedy.
14.
A textbook publisher wants to determine what percentage of college professors either require or recommend that their students purchase textbook packages with supplemental materials, such as study guides, digital media, and online tools. The publisher sends out surveys by e-mail to a random sample of 320 faculty members who have registered with its Web site and have agreed to receive solicitations. The publisher reports that 80% of college professors require or recommend that their students purchase some type of textbook package.
16.
To determine the public’s opinion of the police department, the police chief obtains a cluster sample of 15 census tracts within his jurisdiction and samples all households in the randomly selected tracts. Uniformed police officers go door to door to conduct the survey.
18. Delivery Format The General Social Survey asked, “About how often did you have sex in the past 12 months?” About 47% of respondents indicated they had sex at least once a week. In a Web survey for a marriage and family wellness center, respondents were asked, “How often do you and your partner have sex (on average)?” About 31% of respondents indicated they had sex with their partner at least once a week. Explain how the delivery method for such a question could result in biased responses.
20. Order of the Questions Consider the following two questions:
• (a)Do you believe that the government should or should not be allowed to prohibit individuals from expressing their religious beliefs at their place of employment?
• (b)Do you believe that the government should or should not be allowed to prohibit teachers from expressing their religious beliefs in public school classrooms?
Do you think the order in which the questions are asked will affect the survey results? If so, what can the pollster do to alleviate this response bias? Discuss the choice of the wordprohibit in the survey questions.
• Section 1.6 – numbers 12, 14 (complete a-f only)
12. Assessment To help assess student learning in her developmental math courses, a mathematics professor at a community college implemented pre- and posttests for her students. A knowledge-gained score was obtained by taking the difference of the two test scores.
• (a)What type of experimental design is this?
• (b)What is the response variable in this experiment?
• (c)What is the treatment?
14. Depression Researchers wanted to compare the effectiveness and safety of an extract of St. John’s wort with placebo in outpatients with major depression. To do this, they recruited 200 adult outpatients diagnosed as having major depression and having a baseline Hamilton Rating Scale for Depression (HAM-D) score of at least 20. Participants were randomly assigned to receive either St. John’s wort extract, 900 milligrams per day (mg/d) for 4 weeks, increased to 1200 mg/d in the absence of an adequate response thereafter, or a placebo for 8 weeks. The response variable was the change on the HAM-D over the treatment period. After analysis of the data, it was concluded that St. John’s wort was not effective for treatment of major depression. Source: Richard C. Shelton, MD, et al. “Effectiveness of St. John’s Wort in Major Depression,” Journal of the American Medical Association 285:1978–1986, 2001
• (a)What type of experimental design is this?
• (b)What is the population that is being studied?
• (c)What is the response variable in this study?
• (d)What are the treatments?
• (e)Identify the experimental units.
• (f)What is the control group in this study?