ALLIED MAT130 ALL MODULE HOMEWORK ASSIGNMENT

PART I: SHORT RESPONSE

Directions: Please answer each of the following questions thoroughly.

1. Seventy-two percent of Americans squeeze their toothpaste tube from the top. This and other not-so-serious findings are included in The First Really Important Survey of American Habits. Those results are based on 7,000 responses from the 25,000 questionnaires that were mailed.

a. What is the percentage of questionnaires that were completed based on the number of responses?

b. What drawbacks do you see in using this type of data collecting?

c. As stated, the value of 72% refers to all Americans, so is that 72% a statistic or a parameter?

d. Does the survey constitute an observational study or an experiment?

2. How do a parameter and a statistic differ?

3. How do quantitative data and categorical data differ?

4. How do discrete data and continuous data differ?

5. What is a voluntary response sample, and why is it generally unsuitable for methods of statistics?

6. What is the difference between statistical significance and practical significance?

7. What is the difference between a random sample and a simple random sample?

8. What is the difference between an observational study and an experiment?

9. A New York Times editorial criticized a chart caption that described a dental rinse as one that “reduces plaque on teeth by over 300%.” What is wrong with that statement?

10. Answer the following questions regarding a recent Gallup poll:

a. In a Gallup poll of 976 adults, 68 said that they have a drink every day. What is the percentage of respondents who said that they have a drink every day?

b. Among the 976 adults surveyed, 32% said that they never drink. What is the actual number of surveyed adults who said that they never drink?

11. ABC News conducts an election day poll by randomly selecting voting precincts in New York, then interviewing all voters as they leave those precincts.

a. Does this sampling plan result in a random sample? Explain.

b. Does this sampling plan result in a simple random sample? Explain.

12. A common way of classifying data is to use four levels of measurement: nominal, ordinal, interval, and ratio. Create an example in which each type of measurement is used.

a. Nominal example

b. Ordinal example

c. Interval example

d. Ratio example

13. You have been commissioned to conduct a job survey of graduates from your college. Describe procedures for obtaining a sample of each type:

a. Random

b. Systematic

c. Convenience

d. Stratified

e. Cluster

14. In “Cardiovascular Effects of Intravenous Triiodothyronine in Patients Underdoing Coronary Artery Bypass Graft Surgery” (Journal of the American Medical Association, Vol. 275, No. 9), the authors explain that patients were assigned to one of three groups: (1) a group treated with triidothyronine, (2) a group treated with normal saline bolus and dopamine, and (3) a placebo group given normal saline. The authors summarize the sample design as a “prospective, randomized, double-blind, placebo-controlled trial.” Describe the meaning of each of the following terms in the context of this study:

a. prospective

b. randomized

c. double-blind

d. placebo-controlled

15. Find a professional journal with an article in AAU’s LIRN library that uses a statistical analysis of an experiment and answer the following:

a. Cite the article.

b. Describe and comment on the design of the experiment.

c. Identify one particular issue and determine whether the result was found to be statistically significant.

d. Determine whether that same result has practical significance.

Note: Please visit the Academic Resource Center for a helpful guide on how to use LIRN.

PART II: PROJECT

Directions: This assignment is a course-long project whereby you will work on the project in each module. You will turn in your completed project at the end of Module 8.

Create a survey question to ask others. The following are examples or some survey questions:

1. Choose a random number between 1 and 10 inclusive.

2. What month of the year does your birthday fall on? Write the numeric value from 1 to 12.

3. How many keys are in your possession at this time?

4. How many siblings do you have?

In Module 1, you will submit your survey question to your instructor for approval. Once you are notified of its approval, you may begin conducting a survey using your question.

You will need at least 25 participants and will need to keep the following record for each person:

a. Gender

b. Age

c. Date surveyed

d. Survey response

Please also keep a count, if any, non-willing participants. For example, if you chose the first survey question, then you might have the following records:

In the Module 8 Homework Assignment, you will be asked to analyze your survey results, so please be sure to begin conducting your survey as soon as your question is approved. Try getting 5 participants a week to satisfy the required number of participants.

Welcome to the Module 2 Homework Assignment for MAT 130: Beginning Statistics.

PART I: SHORT RESPONSE

1. A Harris Interactive survey involved 1644 people between the ages of 8 years and 18 years. The accompanying table summarizes the results.

a. Does this table describe a relative frequency distribution? Why or why not?

b. What are some of the conditions for a table to have a relative frequency distribution?

2. Listed below are amounts of strontium-90 (in millibecquerels) in a simple random sample of baby teeth obtained from Pennsylvania residents born after 1979 (based on data from “An Unexpected Rise in Strontium-90 in U.S. Deciduous Teeth in the 1990s,” by Mangano, et. al., Science of the Total Environment). Construct a frequency distribution with eight classes. Begin with a lower class limit of 110, and use a class width of 10. Cite a reason why such data are important. You may use the blank table below or create your own.

155 142 149 130 151 163 151 142 156 133 138 161 128 144 172 137 151 166 147 163 145 116 136 158 114 165 169 145 150 150 150 158 151 145 152 140 170 129 188 156

3. Using the data set above of the amounts of strontium-90 found in baby teeth, find the following:

a. Range

b. Median

c. Mode

d. Mean

4. Construct a stemplot of the amounts of Strontium-90 from problem 3. What does the stemplot suggest about the distribution of those amounts? You may use the table below to create your stemplot.

5. The frequency distribution below summarizes the tar (mg) contains in filtered cigarettes.

Construct a cumulative frequency distribution given the frequency distribution table above.

6. Assume that, as a newspaper reporter, you must graph data showing that increased smoking causes an increased risk of lung cancer. Given that people might be helped and lives might be saved by creating a graph that exaggerates the risk of lung cancer, is it ethical to construct such a graph?

7. In an editorial, the Poughkeepsie Journal printed this statement: "The median price--the price exactly in between the highest and lowest--..." Does that statement correctly describe the median? Why or why not?

8. When the Indianapolis Colts recently won the Super Bowl, the numbers on the jerseys of the active players were 29, 41, 50, 58, 79,..., 10 (listed in the alphabetical order of the player's names). Does it make sense to calculate the mean of those numbers? Why or why not?

9. In statistics, how do variation and variance differ?

10. Which do you think has more variation: the incomes of a simple random sample of 1000 adults selected from the general population, or the incomes of a simple random sample of 1000 statistics teachers? Explain.

11. Listed below are the annual salaries for a simple random sample of NCAA football coaches (based on data from USA Today). How does the standard deviation change if the highest salary is omitted? Compute the standard deviation of the entire list first then compute the standard deviation while omitting the highest salary.

$150,000 $300,000 $350,147 $232,425 $360,000 $1,231,421 $810,000 $229,000

12. Dr. Smith’s Generac generator produces voltage amounts with a mean of 125.0 volts and a standard deviation of 0.3 volt.

a. Using Chebyshev’s theorem, what do we know about the percentage of voltage amounts that are within 3 standard deviations of the mean?

b. What are the minimum and maximum voltage amounts that are within 3 standard deviations of the mean?

13. Bao Xishun is the world’s tallest man with a height of 92.95 in. (or 7 ft, 8.95 in.). Men have heights with a mean of 69.6 in. and a standard deviation of 2.8 in.

a. What is the difference between Bao’s height and the mean height of men?

b. How many standard deviations is that (the difference found in part (a))?

c. Convert Bao’s height to a zscore.

d. Does Bao’s height meet the criterion of being unusual by corresponding to a z score that does not fall between and 2?

14. A physician routinely makes physical examinations of children. She is concerned that a three-year-old girl has a height of only 87.8 cm. Heights of three-year-old girls have a mean of 97.5 cm and a standard deviation of 6.9 cm (based on data from the National Health and Nutrition Examination Survey).

a. Use the range rule of thumb to find the maximum and minimum usual heights of three-year-old girls.

b. Based on the result, is the height of 87.8 cm unusual?

c. Should the physician be concerned?

15. Use the given sorted values below which are the numbers of points scored in the Super Bowl for a recent period of 24 years.

36 37 37 39 39 41 43 44 44 47 50 53 54 55 56 56 57 59 61 61 65 69 69 75

Find the indicated percentile or quartile:

a. P₂₀

b. Q₁

c. Q₃

d. P₇₅

PART II: PROJECT

For this Module 2 Homework Assignment, please submit your response to the following:

Document your progress. Who did you interview? How many people did you interview? If you collected data, please submit it below. If not, please explain what you did to contribute to this assignment this past week.

Directions: This assignment is a course-long project whereby you will work on the project in each module. You will turn in your completed project at the end of Module 8.

Create a survey question to ask others. The following are examples or some survey questions:

1. Choose a random number between 1 and 10 inclusive.

2. What month of the year does your birthday fall on? Write the numeric value from 1 to 12.

3. How many keys are in your possession at this time?

4. How many siblings do you have?

In Module 1, you will submit your survey question to your instructor for approval. Once you are notified of its approval, you may begin conducting a survey using your question.

You will need at least 25 participants and will need to keep the following record for each person:

a. Gender

b. Age

c. Date surveyed

d. Survey response

Please also keep a count, if any, non-willing participants. For example, if you chose the first survey question, then you might have the following records:

In the Module 8 Homework Assignment, you will be asked to analyze your survey results, so please be sure to begin conducting your survey as soon as your question is approved. Try getting 5 participants a week to satisfy the required number of participants.