Question

In: Statistics and Probability

Supposed you were asked to estimate the proportion of 25-30 year olds that have a home...

Supposed you were asked to estimate the proportion of 25-30 year olds that have a home (land line) telephone. In order to make this estimate, you polled 600 people in this age range and the bellows were reported below: [25] pts. Total]

            Home Phone              Frequency

            NO                                    450

            YES                                  150

                                                        600

1. What is the proportion of the sample that report YES, they have a home phone line? [5 pts]

2. What condition must be met in order to calculate a confidence interval to estimate this proportion? Is this condition met? [5 pts.]

3. Develop a 95% confidence interval for the proportion of all of 25-30 year olds that have a home (land line) telephone

Solutions

Expert Solution

1) the proportion of the sample that reports YES, they have a home phone line =

2) The following condition must be met in order to calculate a confidence interval to estimate this proportion.

  1. The sampling method is simple random sampling.
  2. The sample is sufficiently large. As a rule of thumb, a sample is considered "sufficiently large" if it includes at least 10 successes and 10 failures.

3)


Related Solutions

You work for a large retailer and have been asked to estimate the proportion of your...
You work for a large retailer and have been asked to estimate the proportion of your customers that are less than 30 years old. You have sampled a large number of stores and have found that of the 106 customers you have surveyed, 58 are less than 30 years old. Assuming your sample is valid, what is the upper bound of a 99% confidence interval for the population proportion of customers who are less than 30 years old? (Report your...
You have been asked to estimate the value of a home for sale. The subject property...
You have been asked to estimate the value of a home for sale. The subject property has three bedrooms, one bathroom, and is in good condition. A highly comparable property just sold near the subject recently. You will use this recent sale as the comp to estimate value of of the subject property. The comp sold for $134,000. It has three bedrooms, two bathrooms, and is in good condition. Assume bedrooms are worth $5,000 and bathrooms are worth $3,000. What...
You have been asked to estimate the value of a home for sale. The subject property...
You have been asked to estimate the value of a home for sale. The subject property has three bedrooms, two bathrooms, and is in good condition. A highly comparable property just sold near the subject recently. The comp sold for $127,900. It has three bedrooms, one bathroom, and is in good condition. Assume bedrooms are worth $4,500 and bathrooms are worth $2,700. What is the indicated value of the subject based on the comparable sale? (please show all work below...
According to a​ publication, 12.3​% of 18 to 25 dash year dash olds were users of...
According to a​ publication, 12.3​% of 18 to 25 dash year dash olds were users of marijuana in 2000. A recent poll of 1293 randomly selected 18 to 25 dash year dash olds revealed that 176 currently use marijuana. At the 5​% significance​ level, do the data provide sufficient evidence to conclude that the percentage of 18 to 25 dash year dash olds who currently use marijuana has changed from the 2000 percentage of 12.3​%? Use the​ one-proportion z-test to...
You purchase a $325,000 town home and you pay 25 percent down. You obtain a 30-year...
You purchase a $325,000 town home and you pay 25 percent down. You obtain a 30-year fixed-rate mortgage with an annual interest rate of 5.75 percent and monthly payments. After five years you refinance the mortgage for 25 years at a 5.1 percent annual interest rate. After you refinance, what is the new monthly payment (to the nearest dollar)?
Question: do these data represent compelling evidence that the proportion of unemployed 18-29 year-olds that have...
Question: do these data represent compelling evidence that the proportion of unemployed 18-29 year-olds that have diabetes is di↵erent from the proportion of employed 18-29 year-olds that have diabetes? [Counts] Unemployed Employed Total Diabetes 146 717 863 No Diabetes 5709 47057 57766 Total 5855 47774 58629         (a) In the notation we are using in this course, what is the value of n2? (b) In the notation we are using in this course, what is the value of pˆ1?       ...
In order to estimate the mean 30-year fixed mortgage rate for a home loan in the...
In order to estimate the mean 30-year fixed mortgage rate for a home loan in the United States, a random sample of 24 recent loans is taken. The average calculated from this sample is 6.80%. It can be assumed that 30-year fixed mortgage rates are normally distributed with a population standard deviation of 0.5%. Compute 95% and 99% confidence intervals for the population mean 30-year fixed mortgage rate. (Round intermediate calculations to at least 4 decimal places. Round "z" value...
Your organization has asked you to estimate the proportion of current employees who expect to retire...
Your organization has asked you to estimate the proportion of current employees who expect to retire by the age of 65. Develop an appropriate sampling frame and sampling approach to facilitate this task. Note: Your sample must be random. Outline the data collection process you would employ. Additionally, provide a substantive response to the following questions: What considerations need to be made when defining and collecting information from a sample? What problems might you encounter and how frequently might they...
You are looking to estimate the proportion of pet owners that have pet insurance. You know...
You are looking to estimate the proportion of pet owners that have pet insurance. You know from experience that at least 10% have pet insurance. A statistician takes a random sample of 1000 pet owners and creates a 95% confidence interval for the proportion of pet owners that have pet insurance. The confidence interval is [0.23, 0.31]. For each part below, if you can answer the question, provide the answer and an explanation. If you cannot answer the question, provide...
If you wish to estimate the proportion of engineers who have studied probability theory and you...
If you wish to estimate the proportion of engineers who have studied probability theory and you wish your estimation to be correct within 2% with probability 95% or more, how large the sample you would take (a) if you have no idea what the true proportion is, [Ans: 12500] (b) if you are confident that the true proportion is less than 0.2. [Ans: 8000]
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT