1. We describe data using either graphs (e.g., pie chart, histogram) or numbers (e.g., mean, mode) and sometimes both. For each the following variables from the Hi-Definition Televisions Data Set create an appropriate graph, numbers, or both to separately describe the following variables.
1. Price
2. Screen Size
3. Sound Quality
Be sure to include an explanation of why you selected the method used to describe the variable.
2. There are 10 questions on a true-false test. A student feels unprepared for this test and randomly guesses the answer for each of these.
(a) What is the probability that the student gets exactly 7 correct?
(b) What is the probability that the student gets at least 6 correct?
3. Using the Hi-Definition Televisions what is the probability of randomly selecting one TV with a price of over $2500.
4. Assume that the time to complete a construction project is normally distributed with a mean of 60 weeks and a standard deviation of 4 weeks. What is the completion date that the company can be 90% confident the project will be completed?
5. In how many ways can a group of 4 players on the varsity boys basketball team be chosen from a team of 12 players?
6. From the Hi-Definition Television data set and assuming that the data is a random sample from a population of TV prices, use the 90% confidence level in PHStat to estimate the mean TV prices.
7. Using the Salary Data Set,
1. Create a scatter plot to show this relationship between beginning and current salaries
2. Determine the correlation between the variables.
8. Explain why rejecting the null hypothesis does not make the alternative hypothesis true.
9. What is the purpose of statistical inference?
10. What is the difference between sampling error and the standard error of the mean?
11. Use credit Approval Decisions dataset to test the difference in credit scores Homeowner
(Y: Group) and Homeowner (N: Group)
1. Your null and alternative hypotheses;
2. The level of alpha you elect to use and why in terms of Type I or Type II error;
3. Show the output from the analysis;
4. Your interpretation of the results;