A sample is taken from a population of 10,000 to estimate the mean value of a quantity of interest for that population.Question 18Assuming all those sampled produce a response, which one of the following is NOT a valid statement?The larger the sample size the more accurate will be the estimate of the population mean valueFor any given sample size, if the population had been 20,000 rather than 10,000 the accuracy of the estimate of the mean value would have been significantly lower.The greater the variance of the quantity of interest in the population, the less accurate will be the estimate of the population mean valueThe width of any confidence interval for the estimate of the population mean will be halved if the sample size is quadrupled

In designing a sample survey of a population with equal numbers of males and females, a pilot sample is taken which indicates that males have a higher mean of the quantity of interest than females but lower variance.Question 13Which one of the following would produce the most accurate estimate of the population mean when a larger sample is taken?Sampling equal numbers of males and femalesSampling proportionately more males than females, weighting results accordinglySampling proportionately more females than males, weighting results accordinglyCarrying out a purely random sample without regard to gender

Select the true statement regarding the relationship between sampling error and sample size.a.)The sample size can affect the sampling error.b.)In order to decrease sampling error, you must decrease the sample size.c.)The smaller a sample size, the more accurate an estimate can be.d.)The standard error increases as the sample s

Suppose we take repeated random samples of size 20 from a population with a mean of 60 and a standard deviation of 8. Which of the following statements is true about the sampling distribution of the sample mean (x̄)? Check all that apply. The distribution is normal regardless of the shape of the population distribution, because the sample size is large enough. The distribution will be normal as long as the population distribution is normal. The distribution's mean is the same as the population mean 60. The distribution's standard deviation is larger than the population standard deviation of 8.

A social scientist wishes to conduct a survey. She plans to ask a yes/no question to a random sample from the U.S. adult population. One proposal is to select 100 people; another proposal is to select 900 people.Which one of the following is true regarding the standard deviation of the sampling distribution of the sample proportion, p̂, of "yes" responses?Group of answer choicesThe standard deviation of the sampling distribution will be the same for both sample sizes.The standard deviation of the sampling distribution will be 3 times larger with sample size 100.The standard deviation of the sampling distribution will be 9 times smaller with sample size 100.The standard deviation of the sampling distribution will be 9 times larger with sample size 100.The standard deviation of the sampling distribution will be 3 times smaller with sample size 100.

Suppose a population contains 80,000 people. All else being equal, a study based on a population sample that includes which of the following numbers of respondents would you have the most confidence in?A.800B.8000C.80D.8