Statistics

A community college employs 86 full-time faculty members. To gain the​ faculty's opinions about an upcoming building​ project, the college president wishes to obtain a simple random sample that will consist of 9 faculty members. He numbers the faculty from 1 to 89. Complete parts​ (a) and​ (b) below. ​(a) Using the provided random number​ table, the president closes his eyes and drops his ink pen on the table. It points to the digit in row​ 3, column 6. Using this position as the starting point and proceeding​ downward, determine the numbers for the 9 faculty members who will be included in the sample. (b) The president uses technology to produce the following random numbers. 51,63,43,58,13,63,80,18,24,79 Determine the numbers for 9 faculty members who will be included in the sample.

(a) 65,69,67,01,36,03,51,07,78 (b) 51,63,43,58,13,80,18,24,79

A club wants to sponsor a panel discussion on the upcoming national election. The club wants four of its members to lead the panel discussion. Write a short description of the processes that can be used to generate your sample. Obtain a simple random sample of size 4 from the table. (b) Use the portion of the random number table provided to obtain a simple random sample of size 4 from this list. If you start with the first column of the first​ row, work down each column​ (if one must go back to the top of the​ table, do not skip any​ columns), and take the first four numbers between 1 and​ 25, what four members would be selected from the numbered​ list? 85217 73790 83495 81299 11586 51547 26393 14153 02193 11716 21784 41576

(a) Number the names from 1 to 25 and use a random number table to produce 4 different two digit numbers corresponding to the names selected. Your answer is correct. List each name on a separate piece of​ paper, place them all in a​ hat, and pick four. Your answer is correct. (b) 11,02,21,19

Suppose you are the president of the student government. You wish to conduct a survey to determine the student​ body's opinion regarding student services. The administration provides you with a list of the names and phone numbers of the 642 registered students. ​(a) Discuss a procedure you could follow to obtain a simple random sample of 5 students. ​ ​(b) Obtain this sample using the portion of the random number table provided in the problem statement. Start with the first column of the first row and work down each column. (Type the numbers corresponding to the students chosen)

(a) Number the names from 1 to 642 and use a random number table to produce 5 different​ three-digit numbers corresponding to the names selected. Your answer is correct. List each name on a separate piece of​ paper; place them all in a​ hat, and pick five. Your answer is correct. (b) 132,173,581,264,616

Researchers wanted to determine if having a television (TV) in the bedroom is associated with obesity. The researchers administered a questionnaire to 360 ​twelve-year-old adolescents. After analyzing the​ results, the researchers determined that the body mass index of the adolescents who had a TV in their bedroom was significantly higher than that of the adolescents who did not have a TV in their bedroom. Complete parts​ (a) through​ (e) below. ​(a) Why is this an observational​ study? What type of observational study is​ this? (b) What is the response variable in the​ study? Is the response variable qualitative or​ quantitative? What is the explanatory​ variable? What is the response variable in the​ study? Is the response variable qualitative or​ quantitative? (c) Can you think of any lurking variables that may affect the results of the​ study? (d) In the​ report, the researchers​ stated, "These results remain significant after adjustment for socioeconomic​ status." What does this​ mean? (e) Does a television in the bedroom cause a higher body mass​ index? Explain.

(a) The researchers administered a questionnaire to obtain their data without trying to influence an explanatory variable of the study. Cross-Sectional Study (b) The response variable is the body mass index of the adolescents. The response variable is quantitative. The explanatory variable is whether the adolescent has a TV in the bedroom or not. (c) Yes. For​ example, possible lurking variables might be eating habits and the amount of exercise per week. (d) The researchers made an effort to avoid confounding by accounting for potential lurking variables. (e) No. It can only be said that a TV in the bedroom and obesity are associated because the body mass index of the adolescents who had a TV in their bedroom was significantly higher than that of the adolescents who did not have a TV in their bedroom.

As part of a college literature​ course, students must select three classic works of literature from the provided list and complete critical book reviews for each selected work. Write a short description of the processes that can be used to generate a simple random sample of three books. Obtain a simple random sample of size 3 from this list. Use the portion of the random number table provided below to obtain a simple random sample of size 3 from this list. If you start on the left and take the first three numbers between 1 and​ 9, what three books would be selected from the numbered​ list? 63630 93076 42212

A. Number the books from 1 to 9 and use a random number table to produce 3 different one digit numbers corresponding to the books selected. Your answer is correct. C. List each book on a separate piece of​ paper, place them all in a​ hat, and pick three. Your answer is correct. Crime and punishment-The scarlet letter-A tale of two cities

A polling organization contacts 2651 adult men who are 40 to 60 years of age and live in the United States and asks whether or not they had seen their family doctor within the past 6 months. What is the population in the​ study? What is the Sample of the study?

Adult men who are 40 to 60 years of age and live in the United States. The 2651 adult men who are 40 to 60 years of age and live in the United States.

What is an observational​ study? What is a designed​ experiment? Which allows the researcher to claim causation between an explanatory variable and a response​ variable? What is an observational​ study? What is designed experiment? Which allows the researcher to claim causation between an explanatory variable and a response​ variable?

An observational study measures the value of the response variable without attempting to influence the value of either the response or explanatory variables. A designed experiment is when a researcher assigns individuals to a certain​ group, intentionally changing the value of an explanatory​ variable, and then recording the value of the response variable for each group. The Designed Expirement

A student entering a doctoral program in educational psychology is required to select two courses from the list of courses provided as part of his or her program. ​(a) List all possible two​-course selections. ​(b) Comment on the likelihood that EPR 615 and EPR 629 will be selected. (b) There is a nothing in nothing chance that these courses will be selected. (Simplify your​ answer.)

B. 615, 664 Your answer is correct. C. 607, 629 Your answer is correct. D. 656, 664 Your answer is correct. E. 656, 629 Your answer is correct. G. 656, 607 Your answer is correct. H. 656, 615 Your answer is correct. J. 607, 664 Your answer is correct. K. 615, 629 Your answer is correct. M. 664, 629 Your answer is correct. N. 607, 615 Your answer is correct. There is a 1 in 10 chance that these courses will be selected.

Explain what is meant by confounding. What is a lurking​ variable? What is a confounding​ variable? What is a lurking Variable? What is a confounding variable?

Confounding in a study occurs when the effects of two or more explanatory variables are not separated.​ Therefore, any relation that may exist between an explanatory variable and the response variable may be due to some other variable or variables not accounted for in the study. A lurking variable is an explanatory variable that was not considered in a​ study, but that affects the value of the response variable in the study. In​ addition, lurking variables are typically related to explanatory variables in the study. A confounding variable is an explanatory variable that was considered in a study whose effect cannot be distinguished from a second explanatory variable in the study.

What is a​ cross-sectional study? What is a​ case-control study? Which is the superior observational​ study? Why?

Cross-sectional studies are observational studies that collect information about individuals at a specific point in time or over a very short period of time. Case-control studies are observational studies that are​ retrospective, meaning that they require individuals to look back in time or require the researcher to look at existing records. Neither study is always the superior to the other. Both have advantages and disadvantages that depend on the situation.

Determine the level of measurement of the variable below. Dress color

Nominal

Define Statistics

Statistics is the science of​ collecting, organizing,​ summarizing, and analyzing information to draw a conclusion and answer questions. In​ addition, statistics is about providing a measure of confidence in any conclusions.

What is frame?

The frame is a list of the individuals in the population being studied. If the population of interest is all the students at a​ school, the frame would be a list of all the students currectly attending that school.

Determine whether the study depicts an observational study or an experiment. A poll is conducted by a school's math department in which eighth-grade students are asked if they prefer to be in their math class or their English class.

The study is an observational study because the study examines individuals in a sample, but does not try to influence the response variable.

Determine whether the variable is qualitative or quantitative. Age of car driven

The variable is quantitative because it is a numerical measure.

What does it mean when sampling is done without replacement?

When sampling without​ replacement, once an individual is​ selected, the individual is removed from the possible choices for that sample and cannot be chosen again.

Determine whether the underlined numerical value is a parameter or a statistic. Explain your reasoning. For a certain movie, 64.3% of the 112 members of the audience were females.

​ Answer: Parameter because the data set of all 112 audience members is a population.