confidence intervals

The formula for the confidence interval for a variance is _________ . => IV. or II. or III. or I...

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. or There is..

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 ..

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%..

90% confidence interval of a population mean(μ) worked out on a sample size of 50 is, 50 < μ < 56. What is the likely 90% confidence interval of the mean of the same population worked out on a sample size of 100? => 25 < μ < 28 or 51 <..

A random sample of 86 days taken at a large hospital shows that an average of 32 patients were treated per day. The 95% confidence interval of the mean number of patients treated each day at the hospital is between 30 and 34. Find the 95% confidence interval ..

The mean score on a standardized test is 100 with a standard deviation of 8. A random sample of 48 scores was found to have a mean of 98. Find the 95% confidence interval. => The interval is between 97.75 and 102.25 or The interval is between 1.15 and 100 or ..

A sample of 300 tickets purchased during vacation at a travelling center included 45 children's tickets. Find the 95% confidence interval for the true proportion of children, who were traveling during the vacation. => 11% < p <19% or 13% < p <17% or 12.9% < p <..

In a survey of 407 students, 270 indicated that they use a computer at least once a day. Find the 95% confidence interval for the true proportion of students who use computer at least once a day. => 0.614 < p < 0.706 or 0.418 < p < 0.902 or 0.294 < p < 0.386 or..