AP Psychology Research Methods Practice Quiz

The independent variable is the one that is intentionally manipulated by the researcher to observe its effect on another variable. This clear manipulation allows for testing of cause-and-effect relationships.

A control group does not receive the experimental treatment, which provides a basis for comparison with the group that does. This helps in isolating the effects of the independent variable.

Random assignment helps to distribute individual differences evenly across groups. This process minimizes selection bias and enhances the internal validity of the experiment.

The dependent variable is what the researcher measures to see if it is affected by the independent variable. It reflects the outcome of the experiment and is critical in determining the experiment's results.

Operational definitions specify exactly how a variable is measured or manipulated in an experiment. They are essential for clarity and enable other researchers to replicate the study with precision.

Random assignment helps ensure that each participant has an equal chance of being placed in any group. This process minimizes preexisting differences between groups, thereby enhancing the internal validity of the experiment.

A confounding variable is any extraneous variable that can affect the outcome of an experiment if not controlled. Its presence makes it difficult to determine if the independent variable is truly responsible for changes in the dependent variable.

A double-blind procedure prevents both the participants and the researchers from knowing which group the participants are in. This method reduces biases that could influence the interpretation of the results.

A placebo control group receives a non-active treatment to account for any psychological effects of expecting treatment. This group helps determine whether the observed effects are due to the treatment itself rather than participants' expectations.

External validity is about how well the findings can be generalized beyond the study sample. Using a representative sample increases the likelihood that the results will hold true in other settings or populations.

Demand characteristics refer to subtle cues that might inform participants about the study's aims, potentially altering their behavior. Recognizing and minimizing these cues is important to maintain experimental integrity.

Operational definitions outline precisely how variables are measured or manipulated, ensuring clarity and consistency in the research process. This allows other researchers to replicate the study and verify the findings.

Experimental methods are used primarily to establish causal relationships between variables. By controlling the manipulation of the independent variable and observing changes in the dependent variable, researchers can infer causality.

Replication involves conducting a study multiple times to see if the results are consistent. When findings are replicable, they are more reliable and gain greater acceptance within the scientific community.

Control variables are factors that researchers hold constant so that any changes in the dependent variable can be more confidently attributed to the manipulation of the independent variable. Keeping these variables stable reduces the risk of confounding effects.

A randomized control trial helps reduce potential confounding variables by randomly assigning participants to experimental or control groups. This design strengthens causal inferences by controlling for alternative explanations.

When participants self-select into groups, preexisting differences may confound the results, a problem known as selection bias. This undermines internal validity because the groups may not be comparable before treatment.

Using a large, diverse sample improves the generalizability of the findings, which is a key aspect of external validity. The results are more likely to be applicable to a broader population.

When the effect of an independent variable differs across subgroups, it suggests the presence of a moderating variable. In this case, gender appears to moderate the relationship between the drug and memory improvement.

Using a double-blind design coupled with a cover story minimizes the participants' awareness of the true hypothesis. This strategy is effective in reducing demand characteristics and mitigating potential biases.