Question 1

John flips a coin 20 times and observes 8 heads.Those heads are the successes of his study.

Accepted Answer

The statement is true. John flipping a coin 20 times and getting 8 heads means that he had 8 successful outcomes in his study.

Question 2

A fellow student failed to replicate the bystander effect, a well-established effect in social psychology.Because this student failed to find a statistically significant difference in helping behaviors as the number of bystanders increased, it is possible that the student:
A) made a Type II error.
B) made a Type I error.
C) committed a false positive.
D) committed the confounding variable error.

Accepted Answer

A Type II error occurs when a researcher fails to reject a false null hypothesis, meaning they do not find an effect or difference when one actually exists. In this case, the student did not find the expected bystander effect, which could indicate a failure to detect an actual effect due to issues like insufficient power or sample size.

Question 3

Volunteer sampling is a form of convenience sampling.

Accepted Answer

Volunteer sampling involves selecting individuals who are willing to participate in a study, which is a type of convenience sampling.

Question 4

Confirmation bias is the tendency to ignore evidence that goes against one's beliefs.

Accepted Answer

Confirmation bias is a well-established cognitive bias that affects all humans, leading us to seek out information that confirms our existing beliefs and values, and dismissing or discounting evidence that contradicts them.

Question 5

Even though it is not always possible to employ random selection, random assignment should be used whenever possible.

Accepted Answer

Random assignment helps to eliminate selection bias and increase the likelihood that the groups being compared differ only in the treatment being studied. Random selection is not always possible or appropriate, but random assignment should still be used whenever possible in order to ensure that the experimental and control groups are as equivalent as possible at the beginning of the study.

Question 6

External validity is strengthened by the use of volunteer samples.

Accepted Answer

External validity is actually weakened by the use of volunteer samples because volunteer samples are often not representative of the general population. Those who volunteer for studies may have different characteristics and motivations than those who do not volunteer, which limits the generalization of study findings to the broader population.

Question 7

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Which of these constitutes an "exciting" finding?
A) failing to reject the null hypothesis
B) committing a Type I error
C) It is not possible to determine based on the information provided.
D) rejecting the null hypothesis

Accepted Answer

Rejecting the null hypothesis is typically seen as an exciting finding because it suggests that there is a statistically significant relationship or difference between the variables being studied.

Question 8

Convenience samples are used more often in research than random samples.

Accepted Answer

Convenience samples are often easier and cheaper to obtain than random samples, but they may not represent the entire population being studied and can lead to biased results. Despite this, convenience samples are still used more frequently in research due to practical constraints such as time and resources.

Question 9

John flips a coin 20 times and observes 8 heads.Those heads are the outcomes of his study.

Accepted Answer

The answer of John flips a coin 20 times and...

Question 10

A Type I error is to a _____ as a Type II error is to a _____.
A) true positive; true negative
B) false positive; false negative
C) false negative; false positive
D) true negative; false positive

Accepted Answer

Type I error is a false positive, which means rejecting the null hypothesis when it is actually true. Type II error is a false negative, which means failing to reject the null hypothesis when it is actually false.

Question 11

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Which of these constitutes a "boring" finding?
A) failing to reject the null hypothesis
B) committing a Type I error
C) It is not possible to determine based on the information provided.
D) rejecting the null hypothesis

Accepted Answer

Failing to reject the null hypothesis is usually considered a "boring" finding as it means that there was no significant difference or effect observed in the study. On the other hand, rejecting the null hypothesis indicates a significant finding, which is often considered more "exciting" by journals. B is also technically a "boring" finding as it indicates a false positive, but it is less common to report Type I errors in research articles.

Question 12

Random samples are used more often in research than convenience samples.

Accepted Answer

Random samples are ideal for generalizability but are often more difficult and costly to obtain than convenience samples, which are easier and more practical for many research studies.

Question 13

Jenny hypothesized that older adults would score higher on emotional intelligence measures compared to younger adults in her study.If Jenny commits a false-negative error, then she has committed a:
A) Type I error.
B) Type II error.
C) statistical error.
D) sampling bias.

Accepted Answer

If Jenny commits a false-negative error, it means that she failed to reject a false null hypothesis that there is no significant difference between emotional intelligence scores of older and younger adults when in fact there is. This is a Type II error where she accepted a false null hypothesis.

Question 14

Confirmation bias is the tendency to pay attention to evidence that goes against one's beliefs.

Accepted Answer

This statement is incorrect. Confirmation bias is the tendency to pay attention to evidence that supports one's beliefs and to ignore evidence that contradicts those beliefs.

Question 15

A 4-year-old believes that the squeakiness of his shoes on the floor is related to his ability to play basketball.It is likely that there is no real association between the two and this is an example of an illusory correlation.

Accepted Answer

Illusory correlation refers to the perception of a relationship between two variables when none actually exists. The belief that the squeakiness of shoes has a relationship with playing basketball is an example of an illusory correlation.

Question 16

Volunteer sampling is a form of random sampling.

Accepted Answer

Volunteer sampling is not a form of random sampling as it relies on participants who self-select to be part of the sample, rather than being selected randomly from the population. This can lead to biased results as those who volunteer may not be representative of the population as a whole.

Question 17

Jenny hypothesized that older adults would score higher on emotional intelligence measures compared to younger adults in her study.If Jenny erroneously rejected the null hypothesis, she would be committing what type of error?
A) Type I error
B) Type II error
C) statistical error
D) sampling bias

Accepted Answer

If Jenny erroneously rejected the null hypothesis, it means that she would have found a significant difference between the groups when there actually isn't one. This is a Type I error, which is the rejection of a true null hypothesis.

Question 18

A researcher who fails to reject the null hypothesis when the null hypothesis is in fact false has:
A) made a Type II error.
B) made a Type I error.
C) made an illusory correlation.
D) fallen prey to the confirmation bias.

Accepted Answer

Failing to reject the null hypothesis when it is actually false means that the researcher has not detected a true effect, which constitutes a Type II error.

Question 19

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Because of the drive to publish new findings that go against the status quo, the literature is assumed to contain _____ errors.
A) Type I
B) Type II
C) null
D) confirmatory

Accepted Answer

The drive to publish new and exciting findings can lead to the publication of false positives, which are considered Type I errors. Type I errors occur when researchers reject a null hypothesis that is actually true. In other words, they claim to have found a statistically significant effect when the effect is actually not real.

Question 20

Biased samples can be very effective in providing desired results for a researcher.

Accepted Answer

Biased samples are intentionally selected to produce desired results, which can be effective in supporting a researcher's hypothesis or agenda. However, this can also lead to inaccurate or misleading conclusions and undermine the validity and reliability of the research.

Quiz 5: Sampling and Probability

John flips a coin 20 times and observes 8 heads.Those heads are the successes of his study.

A fellow student failed to replicate the bystander effect, a well-established effect in social psychology.Because this student failed to find a statistically significant difference in helping behaviors as the number of bystanders increased, it is possible that the student:

Volunteer sampling is a form of convenience sampling.

Confirmation bias is the tendency to ignore evidence that goes against one's beliefs.

Even though it is not always possible to employ random selection, random assignment should be used whenever possible.

External validity is strengthened by the use of volunteer samples.

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Which of these constitutes an "exciting" finding?

Convenience samples are used more often in research than random samples.

John flips a coin 20 times and observes 8 heads.Those heads are the outcomes of his study.

A Type I error is to a _ as a Type II error is to a _.

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Which of these constitutes a "boring" finding?

Random samples are used more often in research than convenience samples.

Jenny hypothesized that older adults would score higher on emotional intelligence measures compared to younger adults in her study.If Jenny commits a false-negative error, then she has committed a:

Confirmation bias is the tendency to pay attention to evidence that goes against one's beliefs.

A 4-year-old believes that the squeakiness of his shoes on the floor is related to his ability to play basketball.It is likely that there is no real association between the two and this is an example of an illusory correlation.

Volunteer sampling is a form of random sampling.

Jenny hypothesized that older adults would score higher on emotional intelligence measures compared to younger adults in her study.If Jenny erroneously rejected the null hypothesis, she would be committing what type of error?

A researcher who fails to reject the null hypothesis when the null hypothesis is in fact false has:

The text claims that journals tend to prefer "exciting" findings over "boring" ones.Because of the drive to publish new findings that go against the status quo, the literature is assumed to contain _____ errors.

Biased samples can be very effective in providing desired results for a researcher.