AP® Psychology is just as much a class with an abundance of new vocabulary as it is an introduction into the field of psychology. Students often confuse terms because their meanings overlap or they are similar to one another. These terms are often seen on the free-response portion of the exam to determine which students have mastered the meaning and application of terms and which are still working towards mastery.


Understanding the difference between the following five pairs of terms will help students to understand their meaning, keep them distinct from one another, and apply them to practical situations.


  • The Distinction Between Fundamental Attribution Error and Actor-Observer Bias 

Fundamental Attribution Error: The tendency to attribute the behavior of others to internal causes.

Actor-Observer Bias: The tendency to attribute others’ behavior to internal causes while attributing our own behavior to external or situational causes.


In order to keep these principles separate from one another, students can ask themselves if they are only judging someone else’s behavior (fundamental attribution error) or if they are also exhibiting the behavior and making situational attributions about their own behaviors while making dispositional attributions about others’ behavior.



Fundamental Attribution Error: You assume that a student who is late for class is tardy because they are unmotivated and lazy (dispositional attribution).


Actor-Observer Bias: I am late for class because I was stuck in traffic but my colleague is late for class because they are lazy and made no effort to arrive on time.


  • The Difference Between Random Selection and Random Assignment

Random Selection: Random selection is the process of selecting participants from the population to participate in a study. Every person in the population should have an equal chance of being selected to participate in the study. This should be used for all types of studies (correlational, descriptive, experimental).

Random Assignment: Once the researcher has determined who will participate in an experiment, they must randomly place each participant into either the control or experimental condition. All participants should have an equal chance of being placed into either the control or the experimental condition. Not all studies will have this process as there is not always a control group, but this is an essential element of experimental research.



Random Selection: If a researcher wants to determine if a mnemonic device will help students learn material better, they may randomly select from all students at their high school (population) by asking a computer to randomly select 200 student ID numbers.


Random Assignment: Once the participants have been selected, their student ID numbers should once again be placed into a random computer generator and 100 will be assigned to the experimental (mnemonic) condition and 100 to the control condition.


  • The Difference Between Negative Reinforcement and Positive Punishment

Negative Reinforcement: Increases a behavior by removing an aversive stimulus.

Positive Punishment: Decreases a behavior by adding an unpleasant stimulus.


To help students understand the difference between reinforcement and punishment, you can use the analogy of a building that is reinforced to make it stronger—something can be intended as reinforcement but if it does not work in increasing a behavior, it is not reinforcement.


Similarly, punishment must decrease a behavior. Try to avoid words like “good” and “bad.” Negative and positive should be considered in the same context as a math class. Negative subtracts something and positive adds. Ask students to concentrate on the outcome rather than the intent.



Negative Reinforcement: Someone with obsessive-compulsive disorder washes their hands because it decreases their levels of anxiety. Because the anxiety is removed, they are more likely to wash their hands again and again.


Positive Punishment: If a dog runs away on a walk, his owner may add a leash while on their next walk which will decrease the likelihood that the dog will run away again.


  • The Difference Between Availability and Representativeness Heuristics

Availability Heuristic: Judging how likely a certain event is to happen based on how easily information regarding this topic is available.

Representativeness Heuristic: A mental shortcut in which one thinks of the best example or a prototype of a given category.


Availability heuristics are generally about events that stick in your mind because they are vivid and easily retrieved from memory even if they are not typical of that event. Representivenss heuristics represent a category, and it is representative of that category. When asked to consider a chair, students will likely think of a chair in school or one that they sit in often at home. There are many types of chairs, wheelchairs, stools, and beanbag chairs, but these are generally not the most typical examples.



Availability Heuristic: After hearing about a plane crash on television, many individuals will be afraid to fly even though the likelihood that they were in more danger was slight because when they think about flying, this plane crash will be the first thing that pops into their mind.


Representativeness Heuristic: When people think of basketball players, they often think they are tall and may assume that simply because someone is tall, they are interested in basketball.



  • The Difference Between Proactive and Retroactive Interference

Proactive Interference: Older information makes it more difficult to carry out the present task.

Retroactive Interference: Newer information pushes out older, similar information.


In order to keep these terms distinct from one another, it is good to begin with the term “retro,” which most students will understand means old. In retroactive interreference, the old information is forgotten. In proactive interference, it is the current task that is made more difficult because old information is prohibiting the learning of the new information.



Proactive Interference: If a person learns to drive on a stick shift car and then switches to an automatic, they will often look for the clutch and the gear shift, thus disrupting the task at hand (driving the automatic).


Retroactive Interference: If a student had a locker last year and are assigned a new locker this year, they will likely forget their locker combination from the previous year.


Taking a few extra minutes to compare and contrast these terms and have students connect them to real-life situations should go far in helping students to remember the meaning and keep these terms distinct from one another.


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Laura Brandt currently teaches AP® Psychology at Libertyville High School in the Chicago suburbs and online at the Center for Talent Development through Northwestern University. She has taught AP® Psychology since 1997 and has served as a reader, table leader, and question leader for the AP® Psychology Exam. She also serves as an examiner for the IB Psychology. Laura was awarded the Excellence in Teaching award from the American Psychological Association and recognized with the Margaret Moffett Teaching Award from the Society for the Teaching of Psychology. She was also a finalist for the Illinois Teacher of the Year. Laura earned her master’s degree in U.S. History at Northern Illinois University, a master’s degree in Psychology from DePaul University in Chicago, and her administrative certificate form Concordia University. She is currently working on her Ed.D. in Curriculum and Instruction.