Twenty years ago, a very famous psychologist specializing in marriage counseling authored a book detailing the way in which she believed spouses should communicate. She is now interested in the proportion of all couples who bought her book who stayed together. For a random sample of 250 couples who bought her book, she found that 207 of them stayed together. Based on this, compute a 95% confidence interval for the proportion of all couples who bought her book who stayed together. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to two decimal places. What is the lower limit of the  95%  confidence interval?   What is the upper limit of the  95%  confidence interval?

Q: Why does increasing the confidence level result in a larger margin of error?

A: We know that the Margin of error is directly proportional to the test statistic's critical value,…

Q: A political candidate has asked you to conduct a poll to determine what percentage of people support…

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Q: what would be the 90% confidence interval of the true proportion of young adults who have received…

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Q: A polling agency reported that 66 percent of adults living in the United States were satisfied with…

A: The 100 (1 – α)% confidence interval provides an interval estimation of the required population…

Q: A collage professor would like to estimate the proportion of students who pull an *all-nighter,"…

A: Given: n = 100 99% Confidence interval = (0.48 to 0.62) Formula Used: Confidence interval = p^ ±…

Q: Della has over 500 songs on her mobile phone, and she wants to estimate what proportion of the songs…

A: The formula for the confidence interval is , CI=p^± Z*p^1-p^n Where,  p^=the proportion in sample…

Q: . How many of the 3335 subjects used at least one prescription​ medication? b. Construct a​ 90%…

A: n = 3335 p = 0.804

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A:

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Q: The. Nielsen television ratings used a random sample of 2,000 homes and found that 45% of the homes…

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Q: If, based on a sample size of 850​, a political candidate finds that 479 people would vote for him…

A: Given that  n=850 , X=479 Find 95​% confidence interval for his expected proportion of the​ vote?

Q: A political candidate has asked you to conduct a poll to determine what percentage of people support…

A:

Q: Suppose that you will be taking a random sample from a population and that you intend to find a 95%…

A: Solution: The confidence interval for the population mean is calculated by using the following…

Q: A political candidate has asked you to conduct a poll to determine what percentage of people support…

A:

Q: If α = 0.05, then what is the confidence level?

A: Given: α = 0.05   we know that, Confidence level+ α = 1

Q: A political candidate has asked you to conduct a poll to determine what percentage of people support…

A: Solution:There is no estimates available, hence the sample proportion is assumed to be 0.50.The…

Q: If a student provided 90% confidence intervals in all ten questions, how many points would we expect…

A: In the given analysis, we have 10 questions and their correct answers. 10 sample responses from 10…

Q: In order to make the decision for one business, your team constructed a 90% confidence interval, the…

A: For 90% confidence interval, the width of that confidence interval is 500.We have to reduce the…

Q: A manager at ACME Equipment Sale and Rental wondered how offering a free two-year service warranty…

A:

Q: The following table shows the results of a survey in which 1017 adults from the United States, 1060…

A: (1)

Q: 95% confidence interval for the proportion of adults in the United States who say that their…

A:

Q: Suppose that you have obtained data by taking a random sample from a population and that you intend…

A: 95% percent confidence interval will give more accurate estimate of µ than 99% confidence interval.…

Q: Beth wants to determine a 95 percent confidence interval for the true proportion p of high school…

A: Here we need to find the required sample size inorder to construct a 95% confidence interval for the…

Q: In the Laboratory Activity, we used 90% confidence interval instead of 100%, why is this so? Why not…

A: Confidence Interval A confidence interval (CI) is a set of numbers that assess the validity of the…

Q: In general, when you increase the confidence level for a confidence interval using the same sample…

A: As confidence level increases critical value is going to increase .  Here they given sample…

Q: Elly and Drew work together to collect data to estimate the percentage of their classmates who own a…

A: Given that Elly and Drew work together to collect the data to estimate the percentage of their…

Q: Suppose you constructed a 90% confidence interval for the true average GPA of California community…

A: Solution: 1. From the given information, 90% and 80% confidence interval for the true average GPA of…

Q: A television sports commentator wants to estimate the proportion of Americans who "follow…

A: The value of confidence level (CL) is 0.95.

Q: manager at ACME Equipment Sale and Rental wondered how offering a free two-year service warranty on…

A: a.  All necessary assumptions are met: The sampling method for each population is simple random…

Q: In a statistics activity, students are asked to determine if there is a difference in the proportion…

A: Given : Claim : there is a difference in the proportion of times that a spinning penny will land…

Q: In the previous example, you learned that the 95% confidence interval for the true proportion of all…

A: Calculate the point estimate and margin of error used to create this confidence interval.

Q: At one large college, 1867 out of the 2500 students surveyed said they plan to take another science…

A: The known values are, p^=1,867/2,500=0.7468, n=2,500. Using standard normal table, the critical…

Q: n 2013, the Gallup poll asked 1,039 American adults if they believe there was a conspiracy in the…

A: Given data, n=1039 x=634 sample proportion p=x/n =634/1039 =0.61   z-value at 90% confidence is…

Q: In a survey of 3116 adults aged 57 through 85​ years, it was found that 86.2​% of them used at least…

A:

Q: A quality control specialist wants to estimate the percentage of defective batteries within 5% from…

A: A quality control specialist wants to estimate the percentage of defective within 5% from the true,…

Q: As the sample size gets smaller, what happens to the width of your confidence interval? O Wider /…

A: A confidence interval is an interval with a certain probability that a parameter will fall between…

Q: People were surveyed worldwide, being asked the question "How important is acquiring wealth to you?…

A: The sample proportion is calculated using the formula:

Q: The table shows the results of a survey in which separate samples of 400 adults each from the East,…

A: Given : n = 400 p̂= 0.26

Q: Michelle, a student studying music, randomly sampled fellow music majors and asked whether they…

A: Given information- Confidence interval = (0.09, 0.26) We have to find margin of error. We know that-…

Q: Suppose you want to construct an 80% confidence interval for the proportion of businesses that…

A: Given:Margin of Error (E)=3.5%=0.035   For Confidence level 80%, the significance level (α) is…

Q: A recent study of 750 internet users in Europe found that 35% of internet users were women. What is…

A: It is given that the study of 750 internet users in Europe found that 35% of internet users were…

Q: (d) Use the combined data of 80 students, construct a 95% confidence interval estimate of the…

A: Given that  Total students=n=40+40=80 Number of pass students=X=28+32=60

Q: At one large college, 660 out of the 1500 students surveyed said they plan to take another science…

A: Given that,   x=660,n=1500 The sample proportion is, Critical values: By using the standard normal…

Q: The table below gives the number of people that bought either product A, B, or C and their gender.…

A: Hello there! Thank you for the question. According to our honor code can answer only three sub parts…

Q: A political candidate has asked you to conduct a poll to determine what percentage of people support…

A: The formula for the sample size is as follows:

Q: You read about a survey in a newspaper and find that 70% of the 250 people sampled prefer Candidate…

A:

Q: If a retailer would like to estimate the proportion of their customers who bought an item after…

A: Solution: 3. From the given information, confidence level is 0.90 and E=0.03.

Q: confidence interval for the true proportion

A: We have to find out the confidence interval for the true proportion.

Q: In a study by Sallie Mae and Gallup, 323 of the 569respondents said that they paid for their…

A:

Types of Bias

Statistics is the study of data collection, organization, analysis, interpretation, and presentation. Statistical bias is a characteristic of a statistical technique or its findings in which the expected value deviates from the actual root quantitative parameter being estimated. According to the actual definition of bias, it refers to the tendency of a statistic to overestimate or underestimate a parameter.