stats chp 6

A researcher selects a sample of 25 participants from a population with a mean of 10 and a standard deviation of 5. What is the probability of selecting a sample mean that is at least two standard deviations larger than the population mean? .0228 .4772 .9772 equal to the probability of selecting a sample mean that is at least two standard deviations below the mean

0.0228

Which type of sampling is most often applied by researchers in the behavioral sciences? theoretical sampling normal sampling experimental sampling standard normal sampling

experimental sampling

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? 100,000 1,000,000 10,000,000 over 60,000,000 samples

1,000,000

A researcher selects a sample of 64 participants from a population with a mean of 10 and a variance of 16. What is the standard error of the mean? 10 2.0 0.5 There is not enough information to answer this question.

0.5

A researcher randomly selects a sample of participants from a population with a variance of 4. If a researcher selects a sample of 16 participants with a mean of 12, then what is the mean and standard error for the sampling distribution of the mean? mean = 12, standard error = 2 mean = 12, standard error = 1 mean = 12, standard error = 0.5 There is not enough information to answer this question.

12, 0.5

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? 15 30 1,296 4,096

15

A researcher selects a sample of 121 participants from a population with a mean of 32 and a standard deviation of 22. What is the standard error of the mean? 32 2.0 0.5 There is not enough information to answer this question.

2

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? 40 12 2.3 The standard error of the mean is not reported in the article

2.3

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 34 and 40 34 and 38 38 and 44 36 and 40

36 and 40

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 6 and 8 5 and 6 9 and 10 10 and 11

9 and 10

Suppose you select a sample of three people from a population of four (A, B, C, D). Which of the following samples is possible using the experimental sampling strategy? persons A, C, and A persons A, D, and D persons B, C, and D persons B, A, and B

B,C,D

What is the central limit theorem? It explains that sample means will vary minimally from the population mean. It explains that a sampling distribution of possible sample means is approximately normally distributed, regardless of the shape of the distribution in the population. It explains that if we select a sample at random, then on average we can expect the sample mean to equal the population mean. all of the above

It explains that a sampling distribution of possible sample means is approximately normal distributed, regardless of the shape of the distribution in the population

A sampling distribution of the sample mean or variance is a distribution of all measures that could be obtained in a given sample of a given size a distribution of all scores that could be obtained in samples of a given size from one or more populations a distribution of all scores that could be obtained in a population a distribution of all sample means or sample variances that could be obtained in samples of a given size from the same population

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

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? (lots of equations)

all of the above

In terms of characterizing samples, statistical theory was developed using a sampling strategy in which the order of selecting participants matters the same participant can be selected twice in the same sample participants are replaced after being sampled all of the above

all of the above

The sampling distribution of the mean and the sampling distribution of the variance (when dividing SS by n - 1) are both unbiased estimators both follow the central limit theorem are both associated with minimal variance all of the above

are both unbiased estimators

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? .50 equal to the probability of selecting a sample mean that is at most equal to the population mean both A and B none of the above

both A and B

Regardless of the distribution of the population, the sampling distribution of sample means will be approximately normally distributed. What characteristic of the mean explains this? unbiased estimator central limit theorem minimal variance none of the above

central limit theorem

A researcher increases the sample size, which will: increase the value of standard error decrease the value of standard error reduce variability in the population increase variability in the population

decrease the value of standard error

As sample size increases, the standard error of the mean increases decreases can increase or decrease does not change

decreases

The mean of the sampling distribution of sample means is equal to the population mean equal to the population variance both A and B none of the above

equal to the population mean

It happens to be the case that the standard error of the sampling distribution of sample means is minimal is approximately equal to that in the population gets larger as the sample size increases both A and C

is minimal

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 of 13 or larger from this population? equal to the probability of selecting a score above the mean about one standard deviation below the mean less than .03 greater than .31

less than .03

The shape of the sampling distribution of the mean is approximately ________, whereas the shape of the sampling distribution of the variance is approximately ________. normal; normal positively skewed; normal normal; positively skewed positively skewed; positively skewed

normal, positively skewed

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 Researcher A Researcher B They both have the same standard error.

researcher B

Two researchers select a sample for a population with a mean of 12.4 and a standard deviation of 9. Researcher A selects a sample of 30 participants. Researcher B selects a sample of 40 participants. Which sample is associated with a smaller standard error? Researcher A's, because the sample size was smaller. Researcher B's, because the sample size was smaller. Researcher A's, because the sample size was larger. Researcher B's, because the sample size was larger.

researcher B's because the sample size was larger

A researcher selects two samples of 64 participants each. In the first sample the population mean was 10 and the variance was 16. In this 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? Sample 1 Sample 2 None, both samples will have the same value for standard error There is not enough information to answer this question.

sample 1

What values are distributed along the x-axis for a sampling distribution of the sample mean? scores sample means sample variances both B and C

sample means

What values are distributed along the x-axis for a sampling distribution of the sample variance? scores sample means sample variances both B and C

sample variances

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 a conditional procedure a sampling distribution sampling without replacement random sampling

sampling distribution

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. sampling with replacement sampling without replacement

sampling with replacement

A researcher selects from a participant pool of 4 males and 6 females. He determines that the probability of selecting 2 female participants is p = .30. Based on this probability, what strategy did the researcher use to sample participants. sampling with replacement sampling without replacement

sampling without replacement

Each of the following statements are true, except that increasing the sample size will decrease standard error the larger the sample size, the larger the standard error the larger the standard deviation in the population, the larger the standard error both B and C

the larger the sample size, the larger the standard error

Experimental research is typically conducted using a sampling strategy in the order of selecting participants matters the same participant can never be selected twice in the same sample participants are replaced after being sampled all of the above

the same participant can never be selected twice in the same sample

Experimental research is typically conducted using a sampling strategy in which the order of selecting participants matters the same participant can never be selected twice in the same sample participants are replaced after being sampled all of the above

the same participant can never be selected twice in the same sample

The following samples were selected by two researchers. Which is associated with a smaller standard error of the mean? Researcher A: n = 25, = 5, = 7 Researcher B: n = 25, = 32, = 7 Researcher A Researcher B They both have the same standard error.

they both have the same standard error

How is the standard error of the mean typically reported in a graph? using error bars by plotting sample means by listing group names along the x-axis it is never reported in a graph

using error bars

A researcher randomly selects a sample of athletes and reports that their average score on a health and fitness scale is 23. Based on the characteristics of the sample mean, what does this say about the mean in the population? Nothing; it was just a sample. There is no way to know without knowing the size of the sample. It tells us that the mean in the population is no less than 23. We expect that the population mean is equal to 23 because the sample mean is an unbiased estimator of the population mean.

we expect that the population mean is equal to 23 because the sample mean is an unbiased estimator of the population mean