You want to estimate the mean number of friends for all Facebook users. How many users must be in the sample if you want to be 95% confident that the sample mean is within seven friends of the population mean? Assume the standard deviation is 53.  Also, explain the impact of sample size on confidence intervals and explain the connection between the margin of error and size of the confidence interval.

Q: What is the probability that a first grade classroom of 20 students who are chosen randomly from the…

A: Given Information: Mean μ=100 Standard deviation σ=15 Sample size n=20

Q: Unlike most packaged food products, alcohol beverage container labels are not required to show…

A: The summary of statistics is,

Q: The confidence interval for a population porportion is (0.58, 0.78). What the the sample proportion…

A:

Q: The confidence interval for a population porportion is (0.53, 0.73). What the the sample proportion…

A:

Q: The class mean for the exam was 82 with a standard deviation of 6.  There are 37 students in the…

A: We have given that, Mean = 82 , standard deviation σ = 6  sample size n = 37   Standard error of the…

Q: The confidence interval for a population porportion is (0.52, 0.78). What the the sample proportion…

A: Given that, Confidence interval for population proportion is (0.52, 0.78)

Q: Show and explain all steps in calculating the mean and standard deviation of the data set assigned…

A: The question is about descriptive statistics Given data : To explain : 1 ) importance of dividing…

Q: Loretta, who turns 91 this year, has heard that the mean systolic blood pressure among the elderly…

A: The hypothesis for the claim 'mean systolic blood pressure among elderly adults is greater than 120…

Q: Amy is studying the amount of sleep that college students get on class-nights. Earlier sleep…

A: Formula for the sample size needed to estimate a population mean is

Q: C. The test statistic (t (please show your answer to 3 decimal places.) d. The p-value = (Please…

A: We have to test that if mean time is more than 2.06

Q: is 80 a suspect outlier

A: Here given,  One indicator of an outlier is that an observation is more than 2.5 standard deviations…

Q: Find the proportion of scores greater than 70 mean is 90 standard deviation is 10

A: The standard normal distribution:A continuous random variable Z is said to follow standard normal…

Q: Describe about statistical error.

A: In statistics and inference theory, there are various methods through which estimates of true…

Q: The results of a common standardized test used in psychology research is designed so that the…

A: Consider X be a random variable which follows normal distribution indicating the score earned on a…

Q: The mean of a test is 400 and the standard deviation is 75. It is normally distributed. A sample of…

A: 1] Mean μ=400 2] standard deviation σ=75 3] n=25 4] μx¯=400σx¯=σn=7525=15

Q: A paper reported that for a group of 76 college students, the average number of responses changed…

A: The mean number of responses changed from correct answer to incorrect answer on a test The standard…

Q: How do I figure out snowfall is 98 inches per year and the standard deviation is 25 inches.  What…

A: We have to find percentage of the time does the city receive less than 125 inches.

Q: Let's say you have a sample of n = 30, and you know that X = 45 corresponds to z = 1.50 and X = 40…

A:

Q: The manufacturer claims that your new car gets 28 mpg on the highway. You suspect that the mpg is…

A:

Q: A psychologist is studying the self Image of smokers, as measured by the self-Image (SI) score from…

A: Null and alternative hypotheses: The hypothesis which is tentatively fixed up under and tested for…

Q: A psychologist wants to estimate the amount of math anxiety that the population of high school…

A: The psychologist wants to estimate the amount of math anxiety that the population of high school…

Q: An IQ test has a mean of 100 and a standard deviation of 15. An elite engineering company wants to…

A: Let X be the IQ test score of engineer. The mean is μ=100. And a standard deviation σ=15. Assume…

Q: Use the confidence interval to find the margin of error and the sample mean. (1.59,1.89)

A: Given data,Lower limit=1.59Upper limit=1.89Margin of error=?

Q: What is the 75th Percentile of a data set when the Inter Quartile Range (IQR) is 12.5 and the first…

A:

Q: A psychologist wants to estimate the amount of math anxiety that the population of high school…

A:

Q: Lorraine was in a hurry when she computed a confidence interval mean. Because the standard deviation…

A:

Q: Researchers want to estimate the IQ scores for 3 year old children. It is known from a previous…

A: Given:

Q: Shawn Spencer says the average number of homicides in New York is more than 884 per year. Adrian…

A: Given n=62 Standard deviations=14.5 Mean=884

Q: fter finding the range for the age variable, you worry that perhaps this value is being influenced…

A: Given: SPSS output for the variable age,

Q: The average triglyceride level of adult males is 126 milligrams per deciliter. You want to determine…

A: Step 1: From the provided information, Step 2:Hypotheses and test statistic:The hypotheses can be…

Q: A researcher collected sample data for 9 women ages 18 to 24. The sample had a mean serum…

A: Solution: Let X be the serum cholesterol level of all women in the age group 18 to 24. From the…

Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.