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STAT 200 Discrete variables have values that can be measured.  $7.29
STAT 200
1. 
Discrete variables have values that can be measured. 


A) 
True 

B) 
False 
2. 
A(n) __________ probability distribution consists of the finite number of values a random variable can assume and the corresponding probabilities of the values. 
3. 
The number of song requests a radio station receives per day is indicated in the table below. Construct a graph for this data.

4. 
Find the mean of the distribution shown.

5. 
What is the standard deviation and variance of the following probability distribution?

6. 
In a survey, 55% of the voters support a particular referendum. If 30 voters are chosen at random, find the standard deviation and mean of the number of voters who support the referendum. 
7. 
The probability of a success remains the same for each trial in a binomial experiment. 


A) 
True 

B) 
False 
8. 
A certain type of battery has a 2% failure rate. Find the probability that a shipment of 30 batteries has exactly two defective batteries. 
9. 
Which of the following variables are discrete? i. the depth of a submarine ii. the number of torpedoes on a submarine iii. the speed of the submarine 


A) 
ii 

B) 
i and iii 

C) 
i and ii 

D) 
i, ii, and iii 
10. 
Which of the following variables are continuous? i. an automobile's gas mileage ii. the air pressure in an automobile's spare tire iii. an automobile's sticker price 


A) 
None are continuous. 

B) 
i 

C) 
i and ii 

D) 
i, ii, and iii 
11. Extra Credit 5pts.

If a gambler rolls two dice and gets a sum of 10, he wins $10, and if he gets a sum of three, he wins $20. The cost to play the game is $5. What is the expectation of this game? 
12. 
A student takes a 10question, multiplechoice exam with five choices for each question and guesses on each question. Find the probability of guessing 2 or more out of 10 correctly. 
STAT 167 Week 5 Individual Assignment Hypothesis Testing and Correlation Worksheet  $15.00
STAT 167 Week 5 Individual Assignment Hypothesis Testing and Correlation Worksheet
Individual Assignment Hypothesis Testing and Correlation Worksheet
1. What is a hypothesis? What is a hypothesis test (0.5 point)?
2. What is a null hypothesis? What is an alternative hypothesis (0.5 point)?
3. What is a test statistic (0.5 point)?
4. What are significance levels (0.5 point)?
5. Complete this table contrasting the traditional, pvalue, and confidence interval methods of testing a claim about a proportion (1 point).
6. What is the independent variable? What is the dependent variable? Why (0.5 point)?
7. What is the null hypothesis? What is the alternative hypothesis? Is this a onetailed or a twotailed test (0.5 point)?
8. What test statistic will you use? Why (0.5 point)?
9. What is the critical value? What is the value of the test statistic (0.5 point)?
10. Would you accept or reject the null hypothesis? Explain your conclusion in a 100 to 150word summary (0.5 point).
11. What is the null hypothesis? What is the alternative hypothesis? Is this a onetailed or a twotailed test (0.5 point)?
12. What test statistic will you use? Why (0.5 point)?
13. What is the critical value? What is the value of the test statistic (0.5 point)?
14. Would you accept or reject the null hypothesis? Explain your conclusion in a 100 to 150word summary (0.5 point).
15. What is the F distribution? Describe it in no more than 100 words (0.5 point).
16. How and when do researchers use the F distribution? Explain in no more than 150 words (0.5 point).
17. What does it mean if F = 1.0251? Explain in no more than 150 words (0.5 point).
18. Calculate r using Statdisk. Paste the Correlation and Regression report into your response. What is r (0.5 point)?
19. Interpret r and r2. Explain whether there is a significant correlation between women’s age and women’s weight at the 0.05 significance level, and explain how much of the variation in women’s weight is explained by its linear association with women’s age (0.5 point).
STAT 167 Week 5 DQs  $7.50
STAT 167 Week 5 DQs
Discussion Questions
How do researchers test claims about averages? Explain as if to a high school student how to test a claim about a mean. Next, reply to the response of a classmate and ask a question that might be asked by a high school student.
What is the difference between r and r2? Explain and provide example life science data sets, explaining when to use one or the other when interpreting data results.
STAT 167 Week 5  $25.00
STAT 167 Week 5
Individual Assignment Hypothesis Testing and Correlation Worksheet
1. What is a hypothesis? What is a hypothesis test (0.5 point)?
2. What is a null hypothesis? What is an alternative hypothesis (0.5 point)?
3. What is a test statistic (0.5 point)?
4. What are significance levels (0.5 point)?
5. Complete this table contrasting the traditional, pvalue, and confidence interval methods of testing a claim about a proportion (1 point).
6. What is the independent variable? What is the dependent variable? Why (0.5 point)?
7. What is the null hypothesis? What is the alternative hypothesis? Is this a onetailed or a twotailed test (0.5 point)?
8. What test statistic will you use? Why (0.5 point)?
9. What is the critical value? What is the value of the test statistic (0.5 point)?
10. Would you accept or reject the null hypothesis? Explain your conclusion in a 100 to 150word summary (0.5 point).
11. What is the null hypothesis? What is the alternative hypothesis? Is this a onetailed or a twotailed test (0.5 point)?
12. What test statistic will you use? Why (0.5 point)?
13. What is the critical value? What is the value of the test statistic (0.5 point)?
14. Would you accept or reject the null hypothesis? Explain your conclusion in a 100 to 150word summary (0.5 point).
15. What is the F distribution? Describe it in no more than 100 words (0.5 point).
16. How and when do researchers use the F distribution? Explain in no more than 150 words (0.5 point).
17. What does it mean if F = 1.0251? Explain in no more than 150 words (0.5 point).
18. Calculate r using Statdisk. Paste the Correlation and Regression report into your response. What is r (0.5 point)?
19. Interpret r and r2. Explain whether there is a significant correlation between women’s age and women’s weight at the 0.05 significance level, and explain how much of the variation in women’s weight is explained by its linear association with women’s age (0.5 point).
Individual Assignment Final Exam
Discussion Questions
How do researchers test claims about averages? Explain as if to a high school student how to test a claim about a mean. Next, reply to the response of a classmate and ask a question that might be asked by a high school student.
What is the difference between r and r2? Explain and provide example life science data sets, explaining when to use one or the other when interpreting data results.
STAT 167 Week 4 Learning Team Assignment Confidence Intervals in the Life Sciences Presentation  $7.50
STAT 167 Week 4 Learning Team Assignment Confidence Intervals in the Life Sciences Presentation
STAT 167 Week 4 Individual Assignment Distribution, Hypothesis Testing, and Error Worksheet  $15.00
STAT 167 Week 4 Individual Assignment Distribution, Hypothesis Testing, and Error Worksheet
Individual Assignment Distribution, Hypothesis Testing, and Error Worksheet
1. Describe a normal distribution in no more than 100 words (0.5 point).
2. Construct a normal quantile plot in Statdisk, show the regression line, and paste the image into your response. Based on the normal quantile plot, does the data above appear to come from a population of Bigcone Douglasfir tree ages that has a normal distribution? Explain (0.5 point).
3. Calculate the sample mean and standard deviation for the age of Bigcone Douglasfir trees based on the data above. If this accurately represents the population mean and standard deviation for the age of surviving Bigcone Douglasfir trees in the burn area, what is the probability that a randomly selected surviving Bigcone Douglasfir tree from the burn area will be 111 years old or less? Round to the nearest hundredth (0.5 point).
4. Calculate the sample mean and standard deviation for the age of Bigcone Douglasfir trees based on the data above. If this accurately represents the population mean and standard deviation for the age of surviving Bigcone Douglasfir trees in the burn area, what is the probability that a randomly selected surviving Bigcone Douglasfir tree from the burn area will be less than 0 years old? Round to the nearest hundredth. Based on this result, is it logical to assume that the population of age of surviving Bigcone Douglasfir trees in the burn area is normally distributed with the parameters identified. Why or why not (0.5 point)?
5. Describe a standard normal distribution in no more than 100 words (0.5 point).
6. In a standard normal distribution, what is the probability of randomly selecting a value between 2.555 and 0.745? Round to four decimal places (0.5 point).
7. Describe a uniform distribution in no more than 100 words (0.5 point).
8. Describe the sampling distribution of the mean in no more than 100 words (1 point).
9. Explain the central limit theorem in no more than 150 words (1 point).
10. Describe the z distribution in no more than 100 words (0.5 point).
11. Explain when the z distribution can be used in no more than 150 words (0.5 point).
12. Describe the t distribution in no more than 100 words (0.5 point).
13. Explain when the t distribution can be used in no more than 150 words (0.5 point).
14. Describe the chisquare distribution in no more than 100 words (0.5 point).
15. Explain when the chisquare distribution can be used in no more than 150 words (0.5 point).
16. Determine the appropriate approach to conduct a hypothesis test for this claim: Fewer than 5% of patients experience negative treatment effects. Sample data: Of 500 randomly selected patients, 2.2% experience negative treatment effects (0.5 point).
17. Determine the appropriate approach to conduct a hypothesis test for this claim: The systolic blood pressure of men who run at least five miles each week varies less than does the systolic blood pressure of all men. Sample data: n = 100 randomly selected men who run at least five miles each week, sample mean = 108.4, and s = 20.3 (0.5 point).
18. Determine the appropriate approach to conduct a hypothesis test for this claim: The mean sodium content of a 30 g serving of snack crackers is 2,200 mg. Sample data: n = 130 snack crackers, sample mean = 3,100 mg, and s = 570. The sample data appear to come from a normally distributed population (0.5 point).
19. Describe a type I error in no more than 100 words (0.5 point).
20. List two strategies that can minimize the likelihood of a type I error (0.5 point).
21. Describe a type II error in no more than 100 words (0.5 point).
22. List two strategies that can minimize the likelihood of a type II error (0.5 point).
23. In a 250 to 350word essay, compare type I and type II errors and explain the possible negative effects of each error type in the life sciences (2 points).
STAT 167 Week 4  $25.00
STAT 167 Week 4
Week 4
Individual Assignment Distribution, Hypothesis Testing, and Error Worksheet
1. Describe a normal distribution in no more than 100 words (0.5 point).
2. Construct a normal quantile plot in Statdisk, show the regression line, and paste the image into your response. Based on the normal quantile plot, does the data above appear to come from a population of Bigcone Douglasfir tree ages that has a normal distribution? Explain (0.5 point).
3. Calculate the sample mean and standard deviation for the age of Bigcone Douglasfir trees based on the data above. If this accurately represents the population mean and standard deviation for the age of surviving Bigcone Douglasfir trees in the burn area, what is the probability that a randomly selected surviving Bigcone Douglasfir tree from the burn area will be 111 years old or less? Round to the nearest hundredth (0.5 point).
4. Calculate the sample mean and standard deviation for the age of Bigcone Douglasfir trees based on the data above. If this accurately represents the population mean and standard deviation for the age of surviving Bigcone Douglasfir trees in the burn area, what is the probability that a randomly selected surviving Bigcone Douglasfir tree from the burn area will be less than 0 years old? Round to the nearest hundredth. Based on this result, is it logical to assume that the population of age of surviving Bigcone Douglasfir trees in the burn area is normally distributed with the parameters identified. Why or why not (0.5 point)?
5. Describe a standard normal distribution in no more than 100 words (0.5 point).
6. In a standard normal distribution, what is the probability of randomly selecting a value between 2.555 and 0.745? Round to four decimal places (0.5 point).
7. Describe a uniform distribution in no more than 100 words (0.5 point).
8. Describe the sampling distribution of the mean in no more than 100 words (1 point).
9. Explain the central limit theorem in no more than 150 words (1 point).
10. Describe the z distribution in no more than 100 words (0.5 point).
11. Explain when the z distribution can be used in no more than 150 words (0.5 point).
12. Describe the t distribution in no more than 100 words (0.5 point).
13. Explain when the t distribution can be used in no more than 150 words (0.5 point).
14. Describe the chisquare distribution in no more than 100 words (0.5 point).
15. Explain when the chisquare distribution can be used in no more than 150 words (0.5 point).
16. Determine the appropriate approach to conduct a hypothesis test for this claim: Fewer than 5% of patients experience negative treatment effects. Sample data: Of 500 randomly selected patients, 2.2% experience negative treatment effects (0.5 point).
17. Determine the appropriate approach to conduct a hypothesis test for this claim: The systolic blood pressure of men who run at least five miles each week varies less than does the systolic blood pressure of all men. Sample data: n = 100 randomly selected men who run at least five miles each week, sample mean = 108.4, and s = 20.3 (0.5 point).
18. Determine the appropriate approach to conduct a hypothesis test for this claim: The mean sodium content of a 30 g serving of snack crackers is 2,200 mg. Sample data: n = 130 snack crackers, sample mean = 3,100 mg, and s = 570. The sample data appear to come from a normally distributed population (0.5 point).
19. Describe a type I error in no more than 100 words (0.5 point).
20. List two strategies that can minimize the likelihood of a type I error (0.5 point).
21. Describe a type II error in no more than 100 words (0.5 point).
22. List two strategies that can minimize the likelihood of a type II error (0.5 point).
23. In a 250 to 350word essay, compare type I and type II errors and explain the possible negative effects of each error type in the life sciences (2 points).
Team Assignment Confidence Intervals in the Life Sciences Presentation
Discussion Questions
Explain, as if to a high school student, what it means to make a type I error. Then, in the same way, explain what it means to make a type II error. Can you find a realworld example where a type I or type II error would most likely skew the interpretations of a study? Is there a way for scientists to correct for these errors? Why or why not? Next, reply to a classmate’s response and ask a question about the response that you think a high school student would ask.
Explain the circumstances under which a z distribution should be constructed. Under what circumstances should a t distribution be constructed? When can neither a z nor a t distribution be constructed? Provide an example from a particular life science for each of these instances. Next, reply to the response of a classmate with examples from a different life science that you provided and comment on the similarities and differences in the data from different life sciences.
STAT 167 Week 3 Learning Team Assignment Life Sciences Article Analysis  $7.50
STAT 167 Week 3 Learning Team Assignment Life Sciences Article Analysis
STAT 167 Week 3 DQs  $7.50
STAT 167 Week 3 DQs
What is a distribution of sample means? Explain, as if to a high school student, the idea of a distribution of sample means. Include an explanation of why the mean of a distribution of sample means would equal the population mean and of the central limit theorem. Provide an example that would help a high school student understand. Next, reply to a classmate’s response and ask a question about the response that you think a high school student would ask.
Refer to Table 1 in the article “Snail Shells in a Practical Application of Statistical Procedures” in the Electronic Reserve Readings. Find the margin of error, E, with a confidence interval of your choosing (5099%). What is the significance of choosing a confidence interval? What is the difference between selecting a 50% confidence interval versus a 95% confidence interval? What happens to E if the sample size is increased tenfold? Reply to a classmate and include in your response a comparison between the confidence interval you chose and the confidence interval chosen by your classmate. What are the advantages and disadvantages of each?
STAT 167 Week 3 DQs  $7.50
STAT 167 Week 3 DQs
What is a distribution of sample means? Explain, as if to a high school student, the idea of a distribution of sample means. Include an explanation of why the mean of a distribution of sample means would equal the population mean and of the central limit theorem. Provide an example that would help a high school student understand. Next, reply to a classmate’s response and ask a question about the response that you think a high school student would ask.
Refer to Table 1 in the article “Snail Shells in a Practical Application of Statistical Procedures” in the Electronic Reserve Readings. Find the margin of error, E, with a confidence interval of your choosing (5099%). What is the significance of choosing a confidence interval? What is the difference between selecting a 50% confidence interval versus a 95% confidence interval? What happens to E if the sample size is increased tenfold? Reply to a classmate and include in your response a comparison between the confidence interval you chose and the confidence interval chosen by your classmate. What are the advantages and disadvantages of each?