what is a confidence intervals

What is meant by 95% confidence interval of the mean? => 95% of the specific sample means will fall within ± 1.96 standard errors of the population mean. or 95% of the specific sample means will fall within ± 2.58 standard errors of the population mean. o..

95% confidence interval of a population mean worked out on a sample size of 10 is, 0.26 < μ < 0.38. What is the likely 95% confidence interval of the mean of the same population worked out on a sample size of 20? => 0.28 < μ < 0.36..

What are the 95% and 99% confidence intervals for the population mean, if the variance is 0.64? Given that sample size = 60, sample mean = 11.21. => (11.29, 11.371) and (10.933, 11.467) or (10.997, 11.403) and (10.997, 11.403) or (11.01, 11.41) and (10.94, 11.48) or (1..

The formula for the confidence interval for a standard deviation is ________ . => III or II or IV or I..

The 95% confidence interval for the mean number of mangoes in a carton is between 48.12 and 51.88. If a random sample of 27 cartons were used to determine this interval, what was the standard deviation? => 2 or 3 or 4 or 5..

To calculate the confidence interval for variance or standard deviation, a statistical distribution called ______ is needed. => chi-square distribution or binomial distribution or poisson distribution or multinomial distribution..

Select the correct statement(s). I. Increase in sample size will make the confidence interval of the population mean wider. II. A 90% confidence interval will be wider than a 99% confidence interval. III. Sample mean can never be the same ..

The prices of 1 gallon of premium gasoline in U.S dollars in a sample of seven foreign countries is shown. What is the point estimate for the mean? Find the 98% confidence interval of the mean for the prices of 1 gallon of premium gasoline in U.S. 3.80, 3.20, 3.80, 3.5..

An athlete wishes to estimate the mean number of miles run by him per day during practice session. The number of miles run by him on 7 days selected randomly is 7.2, 7, 7.5, 7.8, 7.6, 8 and 7.5. Based on the sample mean, what is the point estimate of the mean? Find the 95% confidence..

A survey of 120 families showed that at least 78 had a computer at home. Find the 99% confidence interval of the true proportion of families who own a home computer. => 64.5% < p < 65.5% or 5.38% < p < 7.62% or 53.8% < p < 76.2% or 60.6% < p < 69.4%..