AP Psychology - Unit 0 Vocab

Unit 0 Vocabulary

confounding variable

A variable other than the independent variable that could potentially influence the dependent variable, leading to inaccurate interpretations of the results

correlation coefficient

A numerical value between -1 and +1 that represents the strength and direction of the relationship between two variables.

dependent variable

The variable that is measured or observed in an experiment and is expected to change as a result of the manipulation of the independent variable.

experimenter bias

The influence of the researcher's expectations or beliefs on the outcomes of an experiment, leading to unintentional bias in data collection or interpretation.

hindsight bias

The tendency to believe, after learning an outcome, that one would have foreseen it. It's often referred to as the "I knew it all along" phenomenon.

histogram

A graphical representation of the distribution of numerical data, where the data is divided into intervals (bins) and the height of each bar represents the frequency or count of data points within each interval.

independent variable

The variable that is manipulated or controlled by the researcher in an experiment to observe its effect on the dependent variable.

mean

The average of a set of values, calculated by summing all values and dividing by the number of values.

median

The middle value in a dataset when the values are arranged in ascending or descending order. If there is an even number of values, the median is the average of the two middle values.

mode

The most frequently occurring value in a dataset.

normal curve

A symmetrical, bell-shaped curve that represents the distribution of scores in a population, with the mean, median, and mode all located at the center.

placebo

An inactive substance or treatment that resembles the experimental treatment, used in research to control for the psychological effects of receiving treatment.

random assignment

The process of assigning participants to experimental or control groups in a way that each individual has an equal chance of being placed in any group, reducing the likelihood of bias.

random sample

A sample in which every member of the population has an equal chance of being selected to participate in the study, increasing the generalizability of the findings.

regression toward the mean

The tendency for extreme or unusual scores on a variable to move closer to the average or mean when measured again.

sampling bias

A bias in which a sample is not representative of the population from which it is drawn, leading to inaccurate or ungeneralizable results.

theory

A well-supported explanation for a phenomenon based on evidence, observation, and experimentation. It integrates and organizes a set of related principles or concepts.