Exam 8: Sampling Methods and the Central Limit Theorem

In the sampling distribution of the sample means,the standard error of the mean will vary according to the size of the sample. As the sample size,n,gets larger,the variability of the sampling distribution of the means gets larger.

Based on the central limit theorem,the sample mean can be used as a good estimator of the population mean,assuming that the size of the sample is sufficiently large.

When computing probabilities for the sampling distribution of the sample mean,the z-statistic is computed as z = .

When dividing a population into subgroups so that a random sample from each subgroup can be collected,what type of sampling is used?

Sampling error is the difference between a sample statistic and its corresponding ________.

According to the central limit theorem,________.

Bones Brothers & Associates prepare individual tax returns. Over prior years,Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes,and the population standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the probability that the mean time for the sample of 100 returns for this year is greater than 92?

If the size of a sample equals the size of the population,we would not expect any error in estimating the population parameter.

A statewide sample survey is to be conducted. First,the state is subdivided into counties. Seven counties are selected at random,and further sampling is concentrated on these seven counties. What type of sampling is this?

The mean of all possible sample means is equal to the population mean.

To study the population of consumer perceptions of new technology,sampling of the population is preferred over surveying the population because ________.