Research and Testing - AP Psychology

The control group in an experimental procedure is designed to provide an unaltered comparison to the experimental or treatment group. The control group in a study of the effects of a vegetarian diet would eat a normal, non-vegetarian diet (or whatever diet the animals ordinarily receive at the zoo).

Independent variables cause change in the dependent variable of an experiment. In this experiment, food spiciness would cause a change in the dependent variable—exercise performance. This variable was changed throughout the experiment in order to measure the induced effect on the subject’s ability to exercise. Remember that while spiciness is sometimes seen as a matter of personal taste, there is at least one quantitative system for measuring it: the Scoville scale.

EEG is the only technique listed in the possible answers section capable of monitoring an electrical current. EEGs, electroencephalograms, are amplified waves of the electrical activity that are found along the surface of the brain.

Functional magnetic resonance imaging or fMRI differs from MRIs in that it shows both the brain's structure and the functions of its constituent parts. They perform this by using a technique to observe blood flow in the brain rather than just magnetic fields that are used by traditional MRIs.

Dr. Schwab is using a behavioral assessment. He is identifying and measuring target behaviors and their controlling variables in an individual's natural environment.

Surveys rely solely on answers that were given to the participants therefore in certain categories (like in sex studies) subjects may give false answers in order to maintain social order. Although it is difficult to get a representative sample of the population, it is possible to get a sample that is large enough and random enough to represent the whole population. Survey questions can readily be made to be objective. Surveys are relatively easy to perform once participation is addressed.

Since case studies only involve one situation, they may lead to the over-generalization of a condition that is rare and/or specific to a certain situation.

A placebo is an inert substance that participants believe is the actual treatment or drug. Placebos have been found to be, in some cases, effective in treatment, and they have also been used to test the efficacy of drugs.

A between-subjects design involves using different participants in the control and experimental groups. There is no overlap in the conditions. Within-subjects design uses the same participants in multiple treatments.

The population would be all the college students that have taken standardized tests in the country the psychologist resides in because a population is all the possible individuals in a group that a sample can be pulled from. It is most likely not possible that the researcher would be able to include the entire population in his study due to the large size.

This example is a double blind study. In a double blind study, both the subjects and researchers do not know which individuals are given the placebo and which are given the actual treatment. This type of study can control for the placebo effect and researcher bias.

When researchers assign study participants to different groups based on chance, such as by using a random number generator or flipping a coin as her, this is an example of random assignment. A method that is not random assignment would be something like assigning all men to one group and all women to another. Random assignment is sometimes confused with random selection, which means choosing study participants at random from the population being studied.

Experimental research designs allow researchers to carefully control each variable measured. This level of control allows researchers to establish causal connections between variables and allows other researchers to know exactly how to repeat the study on their own; however, this control also confines the study to variables that can be observed in a laboratory setting. Unlike descriptive studies, in which participants might not always know they are being observed, experiments force researchers to brief their participants on how they will participate, and allow participants to decline or leave.

PET, positron emission tomography, scans provide a visual display of the brain's activity. They do this by using a radioactive version of glucose that can be traced as it is consumed by the brain. As a result, the technique allows researchers to observe each area of the brain as it consumes the glucose necessary for it to complete a necessary task.

Almost every experiment has a control group, along with one or more experimental groups. A control group must be included to serve as a baseline comparison in contrast to the experimental group. This allows experimenters to determine whether the treatment (the independent variable) creates significant change. The control group is not given experimental treatment, but may be given a placebo. Any differences between the experimental group and control group can be attributed solely to the experimental variable, as this is meant to be the only distinguishng feature between the experimental and control groups.

Qualitative studies do not measure behavior using numbers. Rather, these studies record behaviors such as dialogue, body language, and other observations. Quantitative studies measure variables numerically in order to conduct statistics on the results. All other answer choices are characteristics that are not confined to either type of study alone.

Longitudinal studies retest the same subjects multiple times over a long period of time. Some longitudinal studies can span several decades, depending on the type of data being collected. These types of studies are especially popular in the field of developmental psychology.

Applied research is always conducted with the end goal of trying to solve practical problems. The other choices may seek to help solve various issues, but this is not always the case.

Case studies are rare in psychological research, and are typically used when a subject exhibits a rare and unique symptom pattern. Case studies can also be employed in K-12 school settings to show a child's progress over time in response to various interventions.

Basic research aims to answer questions that are of concern to a particular field. These questions are more of general interest and can be much more for knowledge's own sake as opposed to means toward a specific end. For instance, trying to answer why the sky is blue doesn't have much practical application, but answers an interesting question.

Applied research aims to apply research in some concrete way. For example, researchers may try to answer specific questions so that they can develop a cure or treatment plan for particular illnesses.