A group of researchers is replicating an earlier experiment that indicated that participants who received task-specific feedback were more likely to persist at a task than participants who received more general, encouraging feedback. In an effort to ensure that participants are not treated differently based on the condition that they are in, the researchers automate all of the procedures and follow a written protocol when interacting with the participants. The researchers are trying to minimize:
experimenter expectancy effects.
participant suspicion effects.
In a study examining the effects of heredity on intelligence, researchers compare the correlation of intelligence test scores of identical twins with the correlation of intelligence test scores for fraternal twins. In this experiment, the researcher is assuming that the comparison of identical and fraternal twins is a measure of heredity. This is an example of a ________________ inference.
Researchers interested in studying the effect of happiness on various health outcomes randomly assign each person who comes in to the laboratory to one of two study conditions. However, several people in the study are friends and drove to the study together. The group of friends indicates that they need to be in the same condition of the study so that they can all leave at the together to get home. Accommodating the subjects’ request might threaten validity because of the effect of:
regression to the mean.
In an experiment on the effects of everyday stress on memory, a researcher has participants record every hour how much stress they are feeling and then complete a short-term memory task. The results of the study reveal that everyday stress may affect short-term memory. After evaluating the results of the study, however, the researcher is concerned that people who have high scores on neuroticism questionnaires are more likely to report stress and exhibit memory problems than people who have low scores. The researcher is worried about __________ validity.
__________ validity concerns the generalizability of findings beyond the present study.
A researcher is investigating the ability of aversive punishment to decrease students’ disruptive behaviors in class. She is worried that the number of punishments will vary from student to student and thus will bias the results of the study. The researcher would do well to:
run a pilot test before conducting the study.
manipulate participants’ knowledge about the study.
use a yoked control-group.
use a red herring technique.
A psychologist is examining whether a new type of therapy is effective in the treatment of hallucinations and delusions. The psychologist administers a questionnaire to several patients with schizophrenia and selects those patients with the most severe psychotic symptoms. She randomly assigns the participants to the experimental condition in which they receive a new experimental drug, or the control condition in which they receive the standard medication. She then administers the same test of psychotic symptoms to assess delusional and hallucinations in the two groups at the end of the study. Which of the following threats are not ruled out in the above study?
regression to the mean
A researcher is studying the effects of a new medication that promises to be extremely effective in the treatment of schizophrenia. She randomly assigns severely psychotic patients to three different conditions (standard medication; experimental medication; a wait-list control group) and measures delusional symptoms with the same questionnaire both before and after the study. The researcher uses a wait-list control group in order to:
ensure the ethical treatment of the patients.
rule out history effects.
decrease maturation effects.
rule out testing effects.
A researcher found that whether or not a person is tired impacts how much soda one drinks. She also found that the effect of tiredness was magnified when the soda was cold (versus room temperature). Since the way tiredness impacted soda consumption was different based on the temperature of soda, the researcher reported that there was a(n):
A disordinal interaction is represented by lines that:
intersect and are parallel.
have similar slopes, but are not parallel.
intersect and are not parallel.
have opposite slopes and are parallel.
In an experiment examining the effects of stress on decision making, researchers use two independent variables with two levels each. The first independent variable is temperature of the room (65 degrees and 95 degrees) and the second is noise in the room (present or absent). Researchers randomly assign participants to one of the two temperature conditions and then have the participants perform decision-making tasks in both conditions of the noise variable (present and absent). The researchers allow subjects to rest in between exposure to the noise variable and use counterbalancing of the noise conditions. This experiment uses a(n) _____ design, since subjects are randomly assigned to one independent variable, but exposed to all conditions of the second independent variable.
A researcher is looking at the effects of goal striving (i.e., low, medium, and high) and neuroticism (i.e., low, high) on achievement. The researcher is interested in examining the difference between high and low goal striving for high neuroticism individuals. The researcher is examining a(n):
simple main effect.
two simple contrasts.
Studies with factorial designs are better than students with single-factor designs at capturing the real-life complexity of the real world because they:
include mediator variables.
include more than one independent variables.
eliminate confounding variables.
include several control variables.
Researchers conduct a study to understand whether pre-existing self-esteem and time of day impact how frequently a student raises her/his hand in class to answer a question. Results suggest that both self-esteem and time of day impact hand raising. Pre-existing self-esteem in this study is a(n) _____ variable.
A researcher is conducting an experiment on two predictors of conformity: group size and the presence of a defector (absent, present). The participants are randomly assigned to two different group sizes, one composed of 3 participants and one composed of 8 participants, and then participate in absent and present defector conditions. This is an example of a(n):
between-subjects factorial design with a within-subject variable.
within-subjects factorial design.
within-subjects factorial design with an experimentally manipulated variable.
A psychologist who is investigating the effects of different levels of sweetness on fluid consumption would like to use the same participants in each condition. She is worried, however, that the order of the conditions may influence participants’ responses and decides to use the complete counterbalancing design. In earlier studies, she used 120 participants. In the current study, she would like to use 7 conditions and finds that the number of participants needed increases:
hardly at all.
not at all.
If a researcher wanted to be sure that experimental groups were equivalent, the best method would be to use a _______________ design.
In order to reduce the impact of differences in participant characteristics, a researcher ensures that each participant has an equal probability of assignment to any one of the conditions in the experiment. This is an example of:
A researcher wants to measure the effects of the presence of other people on performance. She has the same participants engage in both experimental conditions, so that each participant performs the task alone and in the presence of other people. This is an example of a study with a ______________ design.
A researcher is investigating the impact of different levels of anxiety on the performance of a speech task. The researcher finds that at moderate levels of anxiety the students perform very well. However, at both lower and higher levels of anxiety, the students perform very poorly. This is an example of a _________________ effect.
Unlike other types of counterbalancing, one type of design does not try to ensure that each condition appears equally often in each position. In a(n) _____________ design, the logic is that on average, for any order of the conditions, each condition will end up in the same average position.
A researcher wants to assess whether a person’s mood affects mathematical reasoning. Participants will complete 50 basic, intermediate and difficult math problems. _______________ may be particularly important in this study because participant fatigue may be a factor.
One of the ways that researchers can control for order effects is to use:
the same subjects.
An industrial organization psychologist is hired by a company to investigate whether a new employee management strategy has resulted in greater employee productivity. A major concern for this psychologist should be:
why the company wanted to initiate the study.
how the results of the study will affect his own theories about efficiency.
ensuring the confidentiality of the employees’ responses.
whether there is even a problem with employee productivity.
A researcher has been hired by a non-profit organization to evaluate the best strategy for implementing and delivering a program designed to treat the needs of the homeless population in the community. The researcher has been hired to conduct a(n):
program theory and design assessment.
In a posttest-only design with a nonequivalent control group, participants in one condition:
and a nonequivalent group are exposed to the treatment, and scores from both groups are obtained after the treatment ends.
and a nonequivalent group are exposed to the treatment, and scores from both groups are obtained before and after the treatment ends.
are exposed to a treatment, a nonequivalent group is not exposed to the treatment, and scores from both groups are obtained after the treatment ends.
are exposed to a treatment, a nonequivalent group is not exposed to the treatment, and scores from both groups are obtained before and after the treatment ends.
_____________ occurs when knowledge, services, or other experiences intended for one group are unintentionally received by another group.
The procedure for the control group appears ______________ the dashed line.
to the left of
to the right of
In order to improve internal validity in a simple interrupted time-series design, researchers need to:
use at least 100 observation periods.
have enough observations to establish pretest and posttest trends in the dependent variable.
have equal number of pretest and posttest observations.
add another treatment intervention.
A researcher examining the effects of a new mathematics instructional technique measures the math scores of the students in the intervention classroom ten times before the intervention and ten times after the intervention. Which of the following still remains a threat to validity?
regression to the mean