Assignment 1- Send Me an Email with Your Contact Information. Specifically

Statistics

Course Assignments

By Ted Cann

Assignment 1- Send me an email with your contact information. Specifically:

a)  Your name

b)  A reachable phone number and email

c)  Any pressing information regarding your personal situation that I may need to know.

Statistics Name:______

Assignment 2- Experimental Design

Date:______

1. A researcher is attempting to determine if there is a correlation between upbringing and the committing of sex crimes as an adult. Which of the following designs is the most appropriate for this observational study?

(a) Obtain a SRS of 4 year old children and follow their development up until the age of 18. Obtain police records at ages 25, 35, 45, 55, 65…death to determine the number of sex crimes committed and analyze.

(b) Obtain a stratified random sample of 4 year old children (strata determined by race) and follow their development to the age the subject moves out on their own. Obtain police records at ages 25, 35, 45, 55, 65…death to determine the number of sex crimes committed and analyze.

(c) Obtain a VRS of individuals who are age 50. Distribute a survey that, among other questions, polls the individual as to whether or not they have committed sex crimes and analyze.

(d) Obtain a SRS of 4 year old children and follow their development up until the age of 18. Observe each individual as they live their daily lives, making certain to take special note of the committing of sex crimes. Document and analyze.

2. A study is conducted to determine if type of music listened to, has any affect on math test scores. Four math classes are selected at random and given a test on basic math concepts. The students’ scores are recorded and analyzed using comparative box-plots. A different type of music is played in each class (rock, rap, country). Which of the following is most appropriate?

(a) There is one explanatory variable and three response variables.

(b) There are three levels of a single explanatory variable.

(c) There are three explanatory variables.

(d) There are three explanatory variables each with one treatment.

3. Which of the following are important in the design of experiments?

I. Control of confounding variables

II. Randomization in assigning subjects to different treatments

III. Replication of the experiment using sufficient numbers of subjects

(A) I and II (B) I and III (E) None of the above gives the complete set of true responses.

(C) II and III (D) I, II, and III

4. Which of the following are true about the design of matched-pair experiments?

I. Each subject might receive both treatments.

II. Each pair of subjects receives the identical treatment, and differences in their responses are noted.

III. Blocking is one form of matched-pair design.

(A) I only (B) II only (C) III only (D) I and III (E) II and III

5. A nutritionist believes that having each player take a vitamin pill before a game enhances the performance of the football team. During the course of one season, each player takes a vitamin pill before each game, and the team achieves a winning season for the first time in several years. Is this an experiment or an observational study?

(A) An experiment, but with no reasonable conclusion possible about cause and effect

(B) An experiment, thus making cause and effect a reasonable conclusion

(C) An observational study, because there was no use of a control group

(D) An observational study, but a poorly designed one because randomization was not used

(E) An observational study, thus allowing a reasonable conclusion of association but not of

cause and effect

6. A town has one high school, which buses students from urban, suburban, and rural communities. Which of the following sample is recommended in studying attitudes toward tracking of students in honors, regular, and below-grade classes?

(A) Convenience sample

(B) Simple random sample (SRS)

(C) Stratified sample

(D) Systematic sample

(E) Voluntary response sample

7. A company has 1000 employees evenly distributed throughout five assembly plants. A sample of 30 employees is to be chosen as follows. Each of the five managers will be asked to place the 200 time cards of their respective employees in a bag, shake them up and randomly draw out six names. The six names from each plant will be put together to make up the sample. Will this method results a simple random sample of the 1000 employees?

(A) Yes, because every employee has the same chance of being selected.

(B) Yes, because every plant is equally represented.

(C) Yes, because this is an example of stratified sampling, which is a special case of simple

random sampling.

(D) No, because the plants are chosen randomly.

(E) No, because not every group of 30 employees has the same chance of being selected.

8. In a study on the effect of music on worker productivity, employees were told that a different genre of background music would played each day and the corresponding production outputs noted. Every change in music resulted in an increase in production. This is an example of

(A) the effect of a treatment unit.

(B) the placebo effect.

(C) the control group effect.

(D) sampling error.

(E) voluntary response bias.

9. In one study on the effect that eating meat products has on weight level, an SRS of 500 subjects who admitted to eating meat at least once a day had their weights compared with those of an independent SRS of 500 people who claimed to be vegetarians. In a second study, an SRS of 500 subjects were served at least one meat meal per day for 6 months, while an independent SRS of 500 others were chosen to receive a strictly vegetarian diet for 6 months, with weights compared after 6 months.

(A) The first study is a controlled experiment, while the second is an observational study.

(B) The first study is an observational study, while the second is a controlled experiment.

(C) Both studies are controlled experiments.

(D) Both studies are observational studies.

(E) Each study is part controlled experiment and part observational study.

10. Scenario: A student wishes to conduct a study to determine if there is a correlation between the number of hours of homework assigned per week in math class and the grade earned in that class.

a. Is this an observational study, or an experiment?

b. What is the best (least-biased) method of sampling? What is the most practical method

of sampling that can be used in this particular case?

c. Describe an effective method for conducting this study.

d. What, if any, are the lurking variables?

e. What do you expect the results of this experiment might be?

f. Should randomization be used? Why or why not?

Statistics

Assignment 3

1

Statistics Name:______

Assignment 4- Measures of Center

Date:______

Problem Set Data:

1

Problem Set: Answer the following questions based on the data given above.

1. With regard to the column entitled, “Reported Maternal Mortality Ratio.”

a. Determine the mean, median, and mode.

b.. If you had to present this data to your classmates and could pick only one measure of central tendency to describe the nature of the data, which would it be and why?

c. What does the phrase “maternal deaths per 100,000 live births” mean?

d. Determine the number of countries that have “Maternal Mortality” rates that are above the:

i. mean

ii. median

iii. mode

2. Given the following data:

a. Determine the mean, median, and mode of the column entitled, “Infant Mortality Rate.”

b. Organize the “Under-five mortality rate” column into a frequency table and determine the mean, median, and mode using the techniques learned in class.

Statistics Name:______

Assignment 5- Measures of Spread

Date:______

1. Listed below are the life expectancies (in years) of men in 28 countries.

46.8 67.8 70.9 74.1 44.2 58.2 37.3 55 62.9 63.6 68.6 64.3 75.1 75.9 59.4

70.1 51.7 53.2 51.6 63.5 73.6 69.4 73.8 69.8 55 68 71.7 51.5

a)  What are the maximum and minimum values?

b)  What is the range of life expectancies?

c)  What is the interquartile range?

d)  Are there any outliers?

2. Find the standard deviation of the salaries listed below.

Statistics Name:______

Assignment 6- Measures of Position

Date:______

The following is a list of the known salaries for the New York Knicks for the 2010-2011 season.

1.  Determine the z-scores for Wilson Chandler and Eddy Curry.

2.  Determine the percentile rank for Danilo Galinari.

3.  Which player represents the 20th percentile? the 65th percentile?

4.  Determine the z-scores for Wilson Chandler and Eddy Curry.

5.  Determine the percentile rank for Danilo Galinari.

6.  Which player represents the 20th percentile? the 65th percentile?

Statistics Name:______

Assignment 7- Basic Probability, Addition Rule

Date:______

1. There are 87 marbles in a bag and 68 of them are green. If one marble is chosen, what is the probability that it will be green?

2. Sal has a small bag of candy containing three green candies and two red candies. While waiting for the bus, he ate two candies out of the bag, one after another, without looking. What is the probability that both candies were the same color?

3. If you roll two dice, what sum is most likely to come up?

4. A card is chosen from a standard deck of 52. Find…

a) P(a 4 or a diamond) b) P(a face card or a club)

c) P(a black card or a card with a number) d) P(a prime or an ace)

5. Jeff and George are skateboarders. Jeff successfully completes a certain stunt 1 out of every 5 attempts while George completes the same stunt 1 out of every 4 attempts. Show how a venn diagram could be used to determine the probability of Jeff or George successfully completing the stunt on the first attempt. What is the probability?

6. Olga places 10 squares, 10 triangles, and 10 rectangles in a hat. On each is placed on of the numbers 0,1,2,…,9. One shape is randomly selected from the hat, calculate each of the following.

a) P(square or a shape with an 8) b) P(triangle or a shape with a 6)

c) P(rectangle or a shape with a 4) d) P(rectangle or a shape with an even number)

e) P(square or a shape with an odd number) f) P(any shape or any shape with a number on it)

Statistics Name:______

Assignment 8- Basic Multiplication Rule

Date:______

1. It's time to get up. You roll out of bed, eyes still closed, and stagger over to your sock drawer. You know that you have three green socks, five red socks, eight blue socks, nine black socks, and twelve white socks scattered at random in the drawer. How many socks will you need to withdraw (keeping your eyes closed) in order to be sure you've got a matching pair?

2. Alexi's wallet contains four $1 bills, three $5 bills, and one $10 bill. If Alexi randomly removes two bills without replacement, determine whether the probability that the bills will total $15 is greater than the probability that the bills will total $2.

3. Using a pair of dice, what is the probability of throwing a sum of nine twice in a row?

4. A player rolls a pair of dice and then picks a card from a deck of cards. What is the probability of throwing a 10 and picking a club?

5. Which of the following events are independent? Dependent?

a. Throwing a 4 with one die and a 6 with another.

b. Picking a 7 from a deck of cards, keeping it, and picking a jack.

c. Flipping a tail with a coin and rolling a 4 with a die.

d. Drawing a spade and drawing a heart from the same deck without replacing the first card.

e. Picking two black marbles from a bag of black and white marbles after replacing the first one.

6. Two letters are chosen, without replacement, at random from the English alphabet. If y is considered to be a consonant, find the probability that

a) both are vowels b) both are consonants.

7. A bag contains 4 white, 3 blue, and 6 red marbles. A marble is drawn from the bag, replaced, and another marble is drawn. Find the probability that

a) both marbles are red b) both marbles are blue

c) the first marble is red and the second is blue d) one marble is red and the other is blue

e) neither is red f) do a-e again and do not replace the marble

8. A box has 3 hockey and 6 football cards.

a. What is the probability of selecting a hockey card, keeping it out, and then selecting another hockey card?

b. What is the probability of selecting a hockey card, keeping it out, and then selecting a football card?

Statistics Name:______

Assignment 9- Complements and Conditional Probability

Date:______

1. A fair die is rolled 12 times. What is the probability of getting at least one three?