Question 1

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30).What was her mean number of study hours per day?​

Accepted Answer

To find the mean, we add up all the study hours and divide by the number of days:
(3+5+9+3+10)/5 = 30/5 = 6
Therefore, Sarah's mean number of study hours per day was 6.

Question 2

A psychologist provides therapy to 20 extremely fearful people,and finds that over the next six months,most become less fearful.The psychologist concludes that the therapy helped.What is a major defect in this study?​

Accepted Answer

The major defect in this study is that it lacks a control group, which means there is no way to compare the improvement in the treatment group to a group that did not receive the therapy. Without a control group, it is impossible to determine if the therapy was truly effective or if the improvement was due to other factors such as the passage of time, a placebo effect, or regression toward the mean.

Question 3

People who believe they have taken a hallucinogenic drug sometimes report hallucinations,even if they took a placebo.Which of these does this phenomenon illustrate?​

Accepted Answer

This phenomenon illustrates demand characteristics, where participants' expectations or beliefs about what they are supposed to feel or experience can influence their reported outcomes, even if they did not actually receive the drug.

Question 4

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30).What was her median number of hours studied per day?​

Accepted Answer

The median is the middle value when the numbers are arranged in order. Arranging Sarah's study hours in ascending order gives 3, 3, 5, 9, 10. The middle value (median) is 5.

Question 5

Demand characteristics have a possible effect on whom?​

Accepted Answer

Demand characteristics refer to cues in an experimental situation that may inadvertently signal to participants what behavior is expected of them or what the hypothesis of the study is. These cues may influence the behavior of participants, leading to biased or inaccurate results. Therefore, demand characteristics primarily affect the participants in an experiment. The other options may be indirectly affected by demand characteristics, but the primary impact is on the participants.

Question 6

How does a researcher reduce the effects of demand characteristics?​

Accepted Answer

Concealing the purpose of the experiment from participants is the best way to reduce the effects of demand characteristics. When participants know the aim of the study, they might alter their behavior or responses to match what they think the researcher wants to see, which can compromise the validity of the results. Discarding data based on being far from the mean could be arbitrary and biased. Allowing participants to choose their group could lead to selection biases. Continuously informing participants about how they are performing could increase demand characteristics.

Question 7

An investigator trying to demonstrate Lamarckian evolution tested rats' ability to learn a swimming maze,and then bred those rats and demonstrated that the next generation learned faster.What was the flaw in this study?​

Accepted Answer

The flaw in the study is that it had no control group, so it is not possible to determine whether the observed improvement in performance was due to Lamarckian evolution or some other factor like selection bias or chance.

Question 8

A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What kind of research is this?​

Accepted Answer

This is a before-and-after study because the same group of students is being compared before and after the intervention of attending the review session. There is no control group, so it is not a true experiment with manipulation and comparison of groups. It is also not single-blind or double-blind because there is no blinding involved.

Question 9

A researcher asks a group of unhappy people to follow the advice in their newspaper horoscopes,and finds that over six months most of them become happier.What is the main problem with this research?​

Accepted Answer

The main problem with this research is that it has no control group. Without a control group, it is impossible to determine if the observed changes in happiness were actually caused by following the horoscopes or if they would have happened anyway. The other options are not relevant to the main issue with the research.

Question 10

If people expect a drug to make them friendlier,they act friendlier.If they expect the same drug to make them less friendly,they act less friendly.What does this tendency illustrate?​

Accepted Answer

This tendency illustrates demand characteristics, which refer to the cues or expectations within an experimental setting that may affect participants' behavior or responses. In this case, participants' expectations about the drug's effects on their friendliness influenced their actual behavior, demonstrating how demand characteristics can affect study outcomes. Blind observers, illusory correlation, and independent variables are not directly relevant to this phenomenon.

Question 11

Under what circumstances are the results of a before-and-after study difficult to interpret?​

Accepted Answer

Without a control group, it is difficult to determine if any observed changes are actually due to the intervention being studied or if they are simply the result of other factors. Other factors could include natural fluctuations or external events that are unrelated to the intervention being studied.

Question 12

Which of the following is undesirable for psychological research and theories?​

Accepted Answer

Demand characteristics refer to cues or hints that participants pick up on from an experimenter, which can affect their behavior or responses. This is undesirable because it can introduce bias or confound the results of a study. Independent variables, parsimony, and falsifiable hypotheses are all desirable for psychological research and theories. Independent variables allow researchers to manipulate a factor of interest and observe its effects on other variables, parsimony refers to the idea that simpler explanations are generally preferable to complex ones, and falsifiable hypotheses are testable statements that can be proven false through empirical evidence.

Question 13

An online dating service reports that 45 percent of their clients started a satisfactory relationship within one year.Why is it difficult to evaluate how impressive that result is?​

Accepted Answer

In order to truly evaluate the success of the online dating service, we would need to know how successful clients were without using the service as compared to those who did use the service. A control group would provide this comparison. Without this, we cannot determine if the 45 percent success rate is impressive or not.

Question 14

In an early study,an investigator trying to demonstrate Lamarckian evolution tested rats' ability to learn a swimming maze,and then bred those rats and demonstrated that the next generation learned faster.What conclusion did the research support,if any?​

Accepted Answer

The study lacked a control group, which is essential for determining if the observed effect (faster learning in offspring) is actually due to the intervention (breeding rats that learned a maze) or if it could be attributed to other factors. Without a control group, it's impossible to draw a definitive conclusion about the inheritance of learned abilities or any other specific cause.

Question 15

A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What conclusion,if any,can we draw,and why?​

Accepted Answer

The improvement in scores alone does not definitively indicate the cause of the improvement. Without a control group (students who did poorly but did not attend the session), it's impossible to determine if the review session was the reason for the improved scores or if other factors were at play.

Question 16

Which of the following helps to alleviate the problems caused by demand characteristics?​

Accepted Answer

A double-blind study is the most effective way to alleviate the problems caused by demand characteristics as it prevents both the participants and researchers from knowing which group they belong to, thus reducing the chances of biased behavior or results. Informed consent, replicability, and statistical significance are important aspects of research, but they do not directly address demand characteristics.

Question 17

What is a "descriptive statistic"?​

Accepted Answer

A descriptive statistic is a mathematical summary of the results obtained from a research study. It is used to describe and summarize the data set, and is often used to make comparisons across groups or to identify patterns within the data. Example of descriptive statistics includes mean, median, mode, standard deviation, etc.

Question 18

Which of these does a psychological researcher try to avoid or minimize?​

Accepted Answer

Psychological researchers try to avoid or minimize demand characteristics, which refer to cues or clues that participants may pick up on during a research study that may affect their behavior or responses. Psychologists want their participants to provide genuine and honest responses, so they try to eliminate any factors that may lead to biased or altered behavior. Falsifiable hypotheses are actually encouraged in psychological research, as it allows for empirical testing and verification of theories. Independent variables and dependent variables are essential components of a psychological study, rather than something to avoid or minimize.

Question 19

What do we call the cues that hint to the research participants what the experimenter hopes to find?​

Accepted Answer

Demand characteristics are the cues given to research participants that hint at what the experimenter hopes to find. These may include subtle verbal or nonverbal cues or the design of the study itself.

Question 20

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30).What was her mode in number of hours studied per day?​

Accepted Answer

The mode is the number that appears most frequently in a data set. In this case, Sarah studied for 3 hours on two different days, which is more frequent than any other number of hours, making 3 the mode.

Quiz 2: Scientific Methods in Psychology

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30) .What was her mean number of study hours per day?

A psychologist provides therapy to 20 extremely fearful people,and finds that over the next six months,most become less fearful.The psychologist concludes that the therapy helped.What is a major defect in this study?

People who believe they have taken a hallucinogenic drug sometimes report hallucinations,even if they took a placebo.Which of these does this phenomenon illustrate?

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30) .What was her median number of hours studied per day?

Demand characteristics have a possible effect on whom?

How does a researcher reduce the effects of demand characteristics?

An investigator trying to demonstrate Lamarckian evolution tested rats' ability to learn a swimming maze,and then bred those rats and demonstrated that the next generation learned faster.What was the flaw in this study?

A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What kind of research is this?

A researcher asks a group of unhappy people to follow the advice in their newspaper horoscopes,and finds that over six months most of them become happier.What is the main problem with this research?

If people expect a drug to make them friendlier,they act friendlier.If they expect the same drug to make them less friendly,they act less friendly.What does this tendency illustrate?

Under what circumstances are the results of a before-and-after study difficult to interpret?

Which of the following is undesirable for psychological research and theories?

An online dating service reports that 45 percent of their clients started a satisfactory relationship within one year.Why is it difficult to evaluate how impressive that result is?

In an early study,an investigator trying to demonstrate Lamarckian evolution tested rats' ability to learn a swimming maze,and then bred those rats and demonstrated that the next generation learned faster.What conclusion did the research support,if any?

A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What conclusion,if any,can we draw,and why?

Which of the following helps to alleviate the problems caused by demand characteristics?

What is a "descriptive statistic"?

Which of these does a psychological researcher try to avoid or minimize?

What do we call the cues that hint to the research participants what the experimenter hopes to find?

During the last five days,Sarah studied 3,5,9,3,and 10 hours (for a total of 30) .What was her mode in number of hours studied per day?