Test 2 (pg 235-242)

Question 1

One of the most critical elements of an expirement is _______.

Answer 1

control

Question 2

If a researcher fails to control for something, the the study is open to _______.

Answer 2

confounds

Question 3

A _____ is an uncontrolled extraneous variable or flaw in an expirement.

Answer 3

confound

Question 4

If a study is confounded, then it is impossible to say whether changes in the dependent variable were caused by the independent variable or by the uncontrolled ___________.

Answer 4

extraneous variable.

Question 5

Maximizing control for _____________ can be very difficult due to dimensions such as personality, intelligence, and rearing issues.

Answer 5

human subjects

Question 6

One of the most basic concerns in an experiment is that the subjects in the control and experimental groups are equivalent in the beginning of the study. A ________ could be used as a means of assuring that the participants in two groups of a study are equivalent on any dimension (such as intelligence) and to prevent confounds due to human variability.

Answer 6

pretest

Question 7

________ is the extent to which the results of an expirement can be attributed to the manipulation of the independent variable rather than to some confounding variable.

Answer 7

internal validity

Question 8

A study with good ____ has no confounds and offers only one explanation for the results.

Answer 8

internal validity

Question 9

Using _________ and _____________ sufficient to address the potential problem of a nonequivalent control group.

Answer 9

random sampling and random assignment

Question 10

When random sampling and random assignment are not used, subject selection or assignment problems may result. In this case, we would have a ___________, not a true experiment.

Answer 10

quasi experimental design

Question 11

_______ is a threat to internal validity in which an outside event that is not a part of the manipulation of the experiment could be responsible for the results.

Answer 11

History effect

Question 12

_______ is a threat to internal validity in which naturally occurring changes within the subjects could be responsible for the observed results.

Answer 12

Maturation

Question 13

________ is a threat to internal validity in which repeated testing leads to better or worse scores.

Answer 13

Testing effect (also called practice effect)

Question 14

_________ is the opposite of the testing effect, when the subject’s performance declines on subsequent tests because they get tired.

Answer 14

fatigue effect (also called negative practice effect)

Question 15

_________ often occurs when individuals are selected for a study because their scores on some measure were extreme - either extremely high or extremely low.

Answer 15

Statistical regression

Question 16

________ is a threat to internal validity in which extreme scores, upon retesting, tend to be less extreme, moving towards the mean. In other words, some of the students did well the first time due to chance or luck.

Answer 16

Regression to the mean.

Question 17

________ is a threat to internal validity in which changes in the dependent variable may be due to changes in the measuring device.

Answer 17

Instrumentation effect

Question 18

An __________ occurs when the measuring device is faulty.

Answer 18

instrumentation effect

Question 19

Problems of consistency in measuring the dependent variable are most likely to occur when the measuring instrument is _____________.

Answer 19

a human observer
(can get better with taking measurements over the course of the study or they could become fatigues with taking measurements.

Question 20

______ is a threat to internal validity in which differential dropout rates may be observed in the experimental and control groups.

Answer 20

Attrition (also called mortality)

Question 21

_______ is a threat to internal validity in which observed changes in the behaviors or responses of subjects may be due to information received from other subjects in the study.

Answer 21

Diffusion of treatment.

Question 22

When subjects in a study are in close proximity to one another, a potential threat to internal validity is _______.

Answer 22

diffusion of treatment

Question 23

What are three ways a researcher could avoid diffusion of treatment?

Answer 23

Conduct the study in large groups or in a short time so the participants do not have time to discuss the study with each other. Stress to the subjects the importance of not discussing the experiment with anyone until it has ended.

Question 24

_______ is a threat to internal validity in which the experimenter, consciously or unconsciously affects the results of the study.

Answer 24

experimenter effect (also called experimenter bias or expectancy effects)

Question 25

When the results of a study are biased by the experimenter’s expectations, this is called the __________.

Answer 25

experimenter effect

Question 26

To prevent the experimenter effect, researchers will often choose to conduct __________.

Answer 26

blind experiments

Question 27

In a ____________, either the experimenter or the subjects are blind to the manipulation being made.

Answer 27

single-blind experiment

Question 28

In a _________, neither the experimenter nor the subject knows the condition in which the subject is serving.

Answer 28

double-blind experiment

Question 29

Sometimes subjects in a study bias the results based on their own expectations. They know they are being observed and hence may not behave naturally, or they may simple behave differently that when they are in more familiar situations. This type of confound is referred to as a ________, the threat to internal validity in which the subject, consciously or unconsciously, affects the results of the study.

Answer 29

subject effect

Question 30

The subject effect is similar to ______. The difference is that “ “ can even occur in observational studies where the subjects don’t even know they are being watched, while subject effect is mainly caused by the participants trying to be “good subjects” for the researcher.

Answer 30

reactivity

Question 31

_______ is a type of subject effect in which subjects try to guess what characteristic the experimenter is in effect “demanding.”

Answer 31

Demand characteristics

Question 32

Subjects may be very sensitive to real or imagined cues from the researcher, referred to as ________.

Answer 32

demand characteristics

Question 33

The _________ is a type of reactivity in which subjects improve or change an aspect of their behavior because they know that they are being studied, rather than in response to the experimental manipulation.

Answer 33

Hawthorne effect

Question 34

The ________ is a classic example of a subject effect.

Answer 34

Hawthorne effect

Question 35

For what was the Hawthorne effect named?

Answer 35

It was named after the Hawthorn plant in Chicago, which was part of Western Electric and the site of a series of experiments in the 30s on how lighting conditions affected worker productivity. The subjects were women who worked at the plant. The researchers discovered that worker productivity tends to increase no matter how the lighting variable was manipulate. Even poor lighting conditions lead to greater productivity. The research concluded that productivity increased simple because the women knew they were part of an experiment and that they were being observed.

Question 36

A special type of subject effect is often present in research on the effects of drugs and medical treatments. Most people report improvement when they are receiving a drug or other medical treatment. Some of this improvement may be caused by a ________.

Answer 36

placebo effect

Question 37

The ________ is the improvement that may not be due to the effects of the treatment but to the subjects expectation that the treatment will have an effect.

Answer 37

placebo effect

Question 38

A _______ (a group or condition in which subjects believe they are receiving treatment but are not) can be used to counter the placebo effect by helping to distinguish between the actual effects of the drug and the placebo effect.

Answer 38

placebo group

Question 39

The placebo group is given an inert pill or substance called a _________, which is a substance that the subjects believe is a treatment.

Answer 39

placebo

Question 40

A limitation of the measuring instrument that decreases its capability to differentiate between scores at the bottom of the scale is called the _______.

Answer 40

Floor effect

Question 41

A limitation of the measuring instrument that decreases its capability to differentiate between scores at the top of the scale is called the _______.

Answer 41

ceiling effect

Question 42

Subjects should receive different scores on the dependent measure on a pretest. If all subjects are scoring about the same (either very high or very low), than a _______ may be present.

Answer 42

ceiling effect

Question 43

Problems in subject selection or assignment may lead to important differences between the subjects assigned to the experimental and control groups. This is called a ______.

Answer 43

nonequivalent control group.

Question 44

A study in measuring mice on a scale using pounds. They all turn out to weigh 1 lb, or the lowest number on the measuring device. This is an example of ____.

Answer 44

the floor effect.

Question 45

A researcher is unknowingly smiles when the subjects are behaving the way he wants, and frowns when they are not behaving the way he wants. This could lead to which threat to internal validity?

Answer 45

The experimenter effect

Question 46

A group of participants in an original study all said that a bracelet helped with their arthritis pain, but later studies on the bracelet showed that it actually did not work. The original study probably suffered from which threat to internal validity?

Answer 46

The placebo effect

Question 47

Subjects are behaving with more kindness that they normally would, because they know they are being watched. This could lead to which threat to internal validity?

Answer 47

The subject effect (they were not behaving naturally)

Question 48

During a study to test the effects of a program aimed at reducing smoking, a group of smokers is randomly selected and half of them are assigned to the control group and the other half to the experimental group. The experimental group participates in the program to reduce smoking, but the heaviest smokers just cannot take the demands of the program and quit. When the posttest is given, only the light to moderate smokers are left in the experimental group, leaving the group inequivalent and thus rendering it pointless to compare the two groups. Which threat to internal validity effected this study?

Answer 48

Attrition (aka mortality) (There was a drop out rate that led to the results being inconclusive)

Question 49

A college student who is going to participate in the study has a roommate who participated in the same study just a month prior. This could lead to which threat to internal validity?

Answer 49

diffusion of treatment (the roommate could have told the other student about the study, which would effect the outcome)

Question 50

College students are involved in a study on stress in which they are participating in 2-month stress reduction program. The posttest happened to fall on the same week as their final exams. Which threat to internal validity could effect this study?

Answer 50

The history effect (The final exams made them stressed, making the results of the test wrong)

Question 51

Subjects took the same math test before and after participating in a special math course. The improvement observed in the scores could be due to which threat of internal validity?

Answer 51

testing effect (They got better on the test because they took it more than once.)

Question 52

If we were studying students who scored in the top 10% on the SAT and we retested them on the SAT only to find out that they did worse the second time instead of the same or better like we expected. This could be due to which threat to internal validity?

Answer 52

regression to the mean (They probably scored so well the first time due to luck)

Question 53

A study of children over a the school year showed an increase in athleticism. The study involved a obstacle course aimed at making the children faster. However, which threat to internal validity could be responsible for the increase in athleticism?

Answer 53

maturation effect (they probably just got more athletic and strong as a result of maturing)

Question 54

An observer is measuring the time it takes a student to answer a question correctly. The observer is using a stop watch to determine the times. The test involves 100 questions and the observer has to ask 10 different students. The speed of the last students to go were far worse than the speed of the first students. Which threat to internal validity probably let to those results?

Answer 54

instrumentation effect (the human observer probably got fatigued from using the stop watch for so long, slowing down their reflexes.)

Question 55

A study is measuring the weight of elephants and their weight end up all being the exact same. It turns out that the scale being used only measured to a certain weight, the same weight that the researchers had for the elephant’s weight. This study was effected by which threat to internal validity?

Answer 55

The ceiling effect