Question 1

Claire knows the z score for her research hypothesis is -2.05, and her critical values are -1.96 and 1.96 for a p value of 0.05.What should she conclude about her hypothesis given these statistics?
A) She should reject the null hypothesis and report the direction of the effect because the score is in a critical region (below -1.96).
B) She should reject the null hypothesis but not report the direction of the effect because she doesn't have enough information.
C) She should fail to reject the null hypothesis because the score is not in a critical region (above 1.96 or below -1.96).
D) She should fail to reject the null hypothesis because she doesn't have enough information.

Accepted Answer

Claire's z score falls in the critical region for a p value of 0.05, indicating that it is unlikely to occur by chance. Therefore, she should reject the null hypothesis and report the direction of the effect.

Question 2

Mehl (2007) published a study in the journal Science reporting the results of an extensive study of 396 men and women comparing the number of words uttered per day by each sex.If Mehl was testing the idea that women talk more than men, what type of hypothesis test would he conduct?
A) one-tailed test
B) two-tailed test
C) nonparametric test
D) z test

Accepted Answer

A one-tailed test is appropriate when the hypothesis predicts a specific direction of the effect, such as the idea that women talk more than men, which implies a direction (more rather than simply different).

Question 3

If we conduct the same study with different samples and get the same results each time, it is:
A) more likely we have an error in our results.
B) more likely the results are accurate.
C) less likely the results are accurate.
D) less likely we can reject the null hypothesis.

Accepted Answer

If we conduct the same study with different samples and get the same results each time, it is more likely the results are accurate as it indicates that the findings can be replicated and are not due to chance or error.

Question 4

The statement "It is hypothesized that men and women will differ on reaction time measures" best illustrates a:
A) one-tailed test.
B) two-tailed test.
C) null hypothesis.
D) z test.

Accepted Answer

This statement suggests a comparison without specifying the direction of difference (i.e., it does not state whether men are expected to have faster or slower reaction times than women), which is characteristic of a two-tailed test. A two-tailed test is used when the research hypothesis does not predict the direction of the effect.

Question 5

When hypothesis testing, a more common approach is to use a _____ rather than a _____.
A) two-tailed test; one-tailed test
B) one-tailed test; two-tailed test
C) null hypothesis; research hypothesis
D) research hypothesis; null hypothesis

Accepted Answer

A two-tailed test is more commonly used because it allows for the possibility of a significant difference in either direction, while a one-tailed test only tests for a significant difference in one specific direction.

Question 6

The symbol for the null hypothesis is _____ and the symbol for the research hypothesis is _____. A) H₁; H₀ B) H₀; H₁ C) $\mu $; M D) $\mu $₀; $\mu $₁

Accepted Answer

The symbol for the null hypothesis is typically denoted by H0 and the symbol for the research hypothesis is typically denoted by H1. Choice B has the correct symbols for each hypothesis.

Question 7

A major reason replication of scientific findings has rarely been attempted is because:
A) there is pressure to not question other researchers' findings.
B) journals tend to publish only new research.
C) of lack of interest in other researchers' work.
D) the media uses these results to criticize previous research.

Accepted Answer

Journals have a preference for publishing novel findings rather than replication studies, which contributes to the rarity of attempts to replicate scientific findings. This preference for novelty can discourage researchers from conducting or submitting replication studies, as they may perceive them to be less likely to be published.

Question 8

The z table only allows for the calculation of percentiles for positive z values.

Accepted Answer

The z table can be used to find the area (or percentile) under the standard normal curve for both positive and negative z values, reflecting the distribution's symmetry around zero.

Question 9

When multiple researchers recruit participants from various locations to replicate findings it is called:
A) crowd-sourcing science.
B) stealing other researchers' work.
C) independent science.
D) new research.

Accepted Answer

Crowd-sourcing science refers to the collaboration of multiple researchers who recruit participants from various locations to replicate findings. This method helps increase the validity and reliability of research studies by including a diverse range of participants and reducing the chance of biased results.

Question 10

The z table only allows for the calculation of percentiles for negative z values.

Accepted Answer

The z table allows for the calculation of percentiles for both negative and positive z values.

Question 11

Rose believes there is a positive correlation between watching violence on television and aggressive behavior.What would be her null hypothesis?
A) Watching violent TV shows increases aggressive behavior.
B) Watching violent TV shows is not related to level of aggressive behavior.
C) Watching violent TV shows causes aggressive behavior.
D) Only aggressive people watch violent TV shows.

Accepted Answer

The null hypothesis is always a statement of no relationship or no difference between variables. In this case, the null hypothesis would be that there is no relationship between watching violent TV shows and level of aggressive behavior. Therefore, option B is the correct choice for the null hypothesis.

Question 12

The statement, "It is hypothesized that participants in a stress condition will perform in a significantly different manner than participants in a control group on a series of memory tasks" best illustrates a:
A) one-tailed test.
B) two-tailed test.
C) null hypothesis.
D) z test.

Accepted Answer

This statement suggests a comparison without specifying the direction of difference (better or worse), which is characteristic of a two-tailed test. A two-tailed test is used when the research hypothesis does not predict the direction of the effect, just that there will be a difference.

Question 13

Use the following to answer questions 
Study Description: Dance Dance Revolution
Unnithan, Houser, and Fernhall (2006) were interested in whether playing the game Dance Dance Revolution (DDR) affected the heart rate of overweight adolescents differently than it affected non-overweight adolescents.Twenty-two adolescents, 10 classified as overweight and 12 as not overweight, played DDR for 12 minutes, while the researchers measured each participant's heart rate.On average, the researchers found no difference between the heart rate of the two groups.
-(Study Description: Dance Dance Revolution) Which statement is the research hypothesis for this study?
A) There will be no difference in the heart rates of the two groups after both groups play Dance Dance Revolution.
B) The heart rate of the overweight group will be faster than that of the non-overweight group after both groups play Dance Dance Revolution.
C) The heart rate of the non-overweight group will be faster that of the overweight group after both groups play Dance Dance Revolution.
D) The heart rates of the overweight group and the non-overweight group will differ after both groups play Dance Dance Revolution.

Accepted Answer

The research hypothesis is that the heart rates of the overweight group and the non-overweight group will differ after both groups play Dance Dance Revolution.

Question 14

If studies fail to replicate:
A) it is unlikely the original study is accurate.
B) science is a failure itself.
C) it can help us better understand the context under which findings might exist.
D) it confuses our understanding of the original study.

Accepted Answer

If studies fail to replicate, it does not necessarily mean that the original study is inaccurate, but rather that the findings may be context-specific. Replication allows for a better understanding of the conditions under which the original study's results could occur.

Question 15

The critical value(s) associated with a p level of 0.05 for a two-tailed hypothesis test using the z statistic is (are):
A) 1.96.
B) 1.65.
C) -1.65 and 1.65.
D) -1.96 and 1.96.

Accepted Answer

The critical value for a two-tailed hypothesis test with a p level of 0.05 is +/- 1.96 using the z statistic. This means that if the test statistic falls outside of the range of -1.96 to 1.96, we can reject the null hypothesis. Therefore, the correct answer is D, which lists both -1.96 and 1.96 as critical values.

Question 16

The behavioral sciences typically use alpha of 0.05.How do they represent this value and what does it mean?
A) A p value, which means scores in the most extreme 2.5 percent on either end of the distribution, will be evidence to reject the null hypothesis.
B) A p value, which means scores 5 percent on either side of the mean, will be evidence to reject the null hypothesis.
C) A z statistic, which means scores in the most extreme 2.5 percent on either end of the distribution, will be evidence to reject the null hypothesis.
D) A z statistic, which means scores 5 percent on either side of the mean, will be evidence to reject the null hypothesis.

Accepted Answer

An alpha of 0.05 is a p-value threshold indicating that if the probability of observing the data, or something more extreme, given that the null hypothesis is true, is less than 5%, the null hypothesis can be rejected. This does not specifically refer to the percentage of scores on either side of the mean but rather to the overall probability of observing the data under the null hypothesis.

Question 17

The crowd-sourcing movement in research is:
A) closed science.
B) new science.
C) open science.
D) dirty science.

Accepted Answer

The crowd-sourcing movement in research is known as open science, as it involves opening up the research process to the public and allowing a crowd of volunteers to contribute to the research. This promotes transparency and collaboration in research, and allows for a diversity of input and perspectives. Closed science refers to traditional, secretive research, while new science and dirty science are not commonly used terms in the context of research.

Question 18

Replication involves conducting:
A) the same study with similar samples and getting the same results each time.
B) the same study with different samples and getting the same results each time.
C) the same study with the same sample and getting the same results each time.
D) two different studies with the same sample and getting the same results each time.

Accepted Answer

Replication involves conducting the same study with different samples and getting the same results each time. This helps to ensure that the results are not specific to one particular sample and can be generalized to a larger population or context.

Question 19

The critical value(s) associated with a p level of 0.05 for a one-tailed hypothesis test using the z statistic is (are):
A) 1.96.
B) 1.65.
C) -1.65 or 1.65.
D) -1.96 and 1.96.

Accepted Answer

For a one-tailed hypothesis test using the z statistic with a p level of 0.05, the critical value is 1.65 for a right-tailed test and -1.65 for a left-tailed test. Therefore, the critical value(s) associated with a p level of 0.05 is -1.65 or 1.65.

Question 20

The statement "It is hypothesized that children who participate in a mentoring program will score lower on depression tests compared to children who do not participate in a mentoring program" best illustrates a:
A) one-tailed test.
B) two-tailed test.
C) null hypothesis.
D) z test.

Accepted Answer

This is a one-tailed test because it is predicting a directional relationship between the independent variable (participation in a mentoring program) and the dependent variable (depression scores). Specifically, it predicts that the mentoring program will reduce depression scores, rather than simply stating that there will be a difference between the two groups.

Quiz 7: Hypothesis Testing With Z Tests

Claire knows the z score for her research hypothesis is -2.05, and her critical values are -1.96 and 1.96 for a p value of 0.05.What should she conclude about her hypothesis given these statistics?

Mehl (2007) published a study in the journal Science reporting the results of an extensive study of 396 men and women comparing the number of words uttered per day by each sex.If Mehl was testing the idea that women talk more than men, what type of hypothesis test would he conduct?

If we conduct the same study with different samples and get the same results each time, it is:

The statement "It is hypothesized that men and women will differ on reaction time measures" best illustrates a:

When hypothesis testing, a more common approach is to use a _ rather than a _.

The symbol for the null hypothesis is _ and the symbol for the research hypothesis is _.

A major reason replication of scientific findings has rarely been attempted is because:

The z table only allows for the calculation of percentiles for positive z values.

When multiple researchers recruit participants from various locations to replicate findings it is called:

The z table only allows for the calculation of percentiles for negative z values.

Rose believes there is a positive correlation between watching violence on television and aggressive behavior.What would be her null hypothesis?

The statement, "It is hypothesized that participants in a stress condition will perform in a significantly different manner than participants in a control group on a series of memory tasks" best illustrates a:

If studies fail to replicate:

The critical value(s) associated with a p level of 0.05 for a two-tailed hypothesis test using the z statistic is (are) :

The behavioral sciences typically use alpha of 0.05.How do they represent this value and what does it mean?

The crowd-sourcing movement in research is:

Replication involves conducting:

The critical value(s) associated with a p level of 0.05 for a one-tailed hypothesis test using the z statistic is (are) :

The statement "It is hypothesized that children who participate in a mentoring program will score lower on depression tests compared to children who do not participate in a mentoring program" best illustrates a: