Exam 7: Probability and Sampling Distributions

Suppose that a researcher selects a sample of participants from a population.If the shape of the distribution in this population is positively skewed,then what is the shape of the sampling distribution of sample means?

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

A researcher selects a sample of size 4 from a population of size 6.How many possible samples of this size can be selected using experimental sampling?

A researcher selects a sample of 169 participants from a population with a mean of 50 and a standard deviation of 13.The probability of selecting a sample mean that is less than 49 is .8413.

The standard error is the sample standard deviation divided by the square root of the sample size.

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

The sample mean is an unbiased estimator of the population mean.

As sample size decreases,the standard error also decreases.

A sampling distribution is a distribution of scores in a population.

A researcher selects a sample of 9 participants from a population with a mean of 8 and a standard deviation of 3.About 14% of the sample means in this sampling distribution should be between a sample mean of

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

An articles 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?

Experimental research is typically conducted using a sampling strategy in which

Each of the following statements are true,except that

A researcher selects two samples of 25 participants each.In the first sample the population mean was 32 and the variance was 8.In this second sample,the population mean was 4 and the variance was 8.Which sample will be associated with a larger standard error of the mean?

There are 25 possible samples of size 2 that can be selected from a population of 5 people using theoretical sampling.

Because the sampling distribution of sample means is normally distributed,we can use the z transformation formula to find probabilities.Which of the following gives the appropriate notation for this formula?

The sampling distribution of the mean has minimum variance.

A researcher selects a sample of 625 participants from a population with a mean of 120 and a standard deviation of 25.The probability of selecting a sample mean that is larger than 125 is close to zero.

A researcher selects from a participant pool of 4 males and 6 females.He determines that the probability of selecting 2 male participants is p = .16.Based on this probability,what strategy did the researcher use to sample participants.