Exam 7: Probability and Sampling Distributions

Without knowing a thing about the population variance,we can expect a randomly selected sample variance (sample variance = SS/df)to equal the population variance on average.

A researcher selects two samples of 64 participants each.In the first sample,the population mean was 10 and the variance was 16.In the second sample,the population mean was 25 and the variance was 9.Which sample will be associated with a larger standard error of the mean?

A researcher selects a sample of size 6 from a population of size 10.How many possible samples of this size can be selected using theoretical sampling?

The standard error of the mean is the standard deviation in a sampling distribution of sample means.

A researcher selects a sample of 100 participants from a population with a mean of 38 and a standard deviation of 20.About 68% of the sample means in this sampling distribution should be between a sample mean of

A researcher selects a sample of 49 participants from a population with a mean of 12 and a standard deviation of 3.5.What is the probability of selecting a sample mean that is at least equal to the population mean?

What is the central limit theorem?

A researcher wants to select a sample of 30 participants from one of two populations.In Population A,the standard deviation is 12.In Population B,the standard deviation is 4.In this example,selecting a sample from Population A will produce the smallest standard error.

What values are distributed along the x-axis for a sampling distribution of the sample variance?

The following samples were selected by two researchers.Which is associated with a smaller standard error of the mean? Researcher A: n = 36, $\mu$ = 12, $\sigma$ = 9 Researcher B: n = 36, $\mu$ = 12, $\sigma$ = 6

As sample size increases,standard error decreases.

A distribution of all sample means or sample variances that could be obtained in samples of a given size from the same population is called

The sampling distribution of the mean and the sampling distribution of the variance (when dividing SS by n - 1)

If a researcher selects a sample of 64 participants from a population with a variance of 16,then the standard error of the mean will be 2.0.

Researchers typically sample with replacement,although the development of statistical theory was based on the use of sampling without replacement.

An article states that a sample of 40 participants took 12 ± 2.3 (M ± SEM)seconds to complete a cognitive assessment.Which value is the standard error of the mean?

How is the standard error of the mean typically reported in a graph?

The sample variance is an unbiased estimator of the population variance

As sample size increases,the standard error of the mean

Which of the following allows researchers to use the standard normal distribution to estimate the probability of selecting sample means?