Social psychology studies how situations shape behaviour, while personality psychology focuses on individual traits. Kurt Lewin's equation, B = f(P, S), captures the idea that behaviour is a product of both the person and their environment. The research methods chapter covers how psychologists test ideas (theories, hypotheses, experiments versus correlations) and the safeguards that keep those tests trustworthy (random sampling, random assignment, internal and external validity). Chapter 2 turns inward: how we build a self-concept through schemas, social comparison, and cultural context, and how biases like the self-serving bias and false consensus warp the picture.
Difficulty: Introductory. Prerequisites: None. These are the foundational chapters of the course.
Chapters 1 and 2 set the stage for everything else in social psychology. Chapter 1 introduces the discipline (how it differs from personality psychology) and the toolkit researchers use to study human behaviour: theories, hypotheses, sampling, experimental design, and the distinction between correlational and experimental research. Chapter 2 shifts the lens onto the self, covering how we construct a self-concept, how culture shapes identity, how we measure and protect self-esteem, and how cognitive biases (self-serving bias, false consensus, false uniqueness) distort our self-perception. If you understand these two chapters, you have the vocabulary and the critical-thinking framework the rest of the course builds on.
Social psychology
The study of how situations and environmental influences shape behaviour.
In simple terms, it asks: "How does the world around you make you act the way you do?"
Personality psychology
The study of individual traits and why different people behave differently in the same situation.
Think of it as the flip side of social psych: person-centred rather than situation-centred.
Kurt Lewin's equation: B = f(P, S)
Behaviour (B) is a function of the Person (P) and the Situation (S). Both internal dispositions and external circumstances determine what someone does.
In simple terms, who you are plus where you are equals what you do.
Theory
A set of principles that explain and predict observed events. Theories summarise observations and generate predictions.
Hypothesis
A testable prediction describing a relationship that may exist between events. Hypotheses allow us to test theories.
Representative sample
A sample that accurately reflects the characteristics of the population being studied.
Random sample
A sampling method in which every person in the population has an equal chance of being included.
Random assignment
Assigning participants to experimental conditions so that every person has the same chance of being placed in any given condition. This eliminates extraneous factors.
In simple terms, it is the gold standard for making sure groups are equivalent before you do anything to them.
Framing effect
A cognitive bias in which people make different decisions based on how information is presented, rather than on the information itself.
Demand characteristics
Cues in an experiment that signal to participants what behaviour the researcher expects.
Mundane realism
The degree to which an experiment is superficially similar to everyday situations.
Experimental realism
How psychologically engaging and involving an experiment feels to participants.
Internal validity
The confidence with which you can conclude that the independent variable, and not something else, caused the observed effect.
External validity
The extent to which results can be generalised to a larger population or to other settings.
Correlational research
The study of naturally occurring relationships between variables. It examines variables in a natural setting, but cause-and-effect conclusions are ambiguous. The correlation coefficient (r) ranges from -1 to +1; r = 0 means no relationship.
Experimental research
Research that seeks clues to cause-and-effect relationships by manipulating one or more factors. It uses random assignment and controlled conditions.
Social psychology examines situational and environmental influences on behaviour. Personality psychology focuses on individual traits and why people behave differently in the same situation. Kurt Lewin's equation, B = f(P, S), bridges the two: behaviour is always a joint product of the person and the situation.
A theory organises observations and generates predictions.
A hypothesis is a specific, testable prediction derived from a theory.
Researchers test hypotheses using data, and the results either support or fail to support the theory.
A representative sample mirrors the characteristics of the target population.
A random sample gives every member of the population an equal chance of selection.
Random assignment places participants into conditions at random, eliminating pre-existing differences between groups.
The distinction matters: random sampling affects external validity (can you generalise?), while random assignment affects internal validity (can you infer causation?).
Surveys and questionnaires must be constructed so they do not bias responses.
The framing effect means how a question is worded can change the answer.
Demand characteristics are cues that tip participants off to the "right" response.
Mundane realism is how closely the experiment mirrors everyday life; experimental realism is how psychologically absorbing it feels.
Internal validity: confidence that the independent variable caused the observed effect. Strengthened by random assignment and tight controls.
External validity: confidence that results generalise beyond the lab. Strengthened by representative samples and field settings.
These two often trade off: a tightly controlled lab study has high internal validity but may lack external validity, and vice versa.
Lab vs field research
Lab research takes place in a controlled setting with maximum control over variables.
Field research takes place in everyday, natural settings with less control.
Correlational vs experimental research
Correlational research measures naturally occurring relationships. It can show that two variables move together, but it cannot establish that one causes the other.
Experimental research manipulates an independent variable and measures its effect on a dependent variable. Random assignment and controlled conditions allow causal conclusions.
Self-concept
What we know and believe about ourselves, the sum of all our self-schemas.
Self-schemas
Mental frameworks or belief systems you hold about yourself. Schemas more broadly are the mental templates we use to organise the world.
Social comparison
Evaluating your own opinions and abilities by comparing yourself with others.
Looking-glass self
Using how we think others perceive us as a mirror for perceiving ourselves.
In simple terms, "I am what I think you think I am."
Spotlight effect
The belief that others are paying more attention to our appearance and behaviour than they actually are.
Illusion of transparency
The illusion that our concealed emotions leak out and can be easily read by others.
Individualism
A cultural orientation that prioritises personal goals over group goals and defines identity through personal characteristics. Prevalent in Western cultures.
Collectivism
A cultural orientation that prioritises group goals and defines identity through group membership.
Self-esteem
A person's overall self-evaluation or sense of self-worth. It is high when we feel good about domains we consider important.
Self-efficacy
The sense that one is competent and effective at a particular task. It leads people to set challenging goals and persist.
Think of it this way: self-esteem is liking yourself overall; self-efficacy is believing you can do a specific thing.
Rosenberg Self-Esteem Scale
A widely used 1-to-10 scale measuring how positively a person feels about themselves.
Implicit Associations Test (IAT)
A computer-based assessment that uses reaction time to measure how quickly people associate concepts, revealing implicit biases.
Self-serving bias
The tendency to attribute positive outcomes to our own actions and negative outcomes to external factors.
False consensus
Overestimating how much others share our opinions, attitudes, or behaviours. Example: thinking "everyone cheats a bit" because you do.
False uniqueness
Underestimating how common our abilities, traits, or positive behaviours are. Example: believing nobody else cares about something that many people care about.
Unrealistic optimism
An unjustified belief that bad things are less likely to happen to us than to others, which can increase vulnerability.
Defensive pessimism
Deliberately lowering expectations and imagining problems in advance so as to prepare better and ultimately perform well.
Our self-concept is assembled from self-schemas (mental frameworks about who we are), social comparisons (measuring ourselves against others), and reflected appraisals (the looking-glass self: inferring what others think of us and using that as a mirror).
Two common perceptual distortions sit alongside these processes:
The spotlight effect: we overestimate how much others notice us.
The illusion of transparency: we believe our hidden feelings are more visible than they are.
Individualist cultures (common in the West) stress personal goals and personal identity.
Collectivist cultures stress group goals and group identity.
This distinction shapes how people describe themselves, what they value, and how they experience self-esteem.
Self-esteem is global ("Do I like myself?"). Self-efficacy is task-specific ("Can I do this?"). High self-efficacy in a domain predicts persistence and goal-setting; self-esteem is highest when we feel competent in areas we personally value.
Measurement tools include the Rosenberg Self-Esteem Scale (explicit) and the Implicit Associations Test or Name-Letter Effect Test (implicit).
Self-serving bias: credit yourself for successes, blame the situation for failures.
False consensus: assume everyone thinks the way you do.
False uniqueness: assume your good qualities are rarer than they are.
These three biases work together to maintain a flattering self-image.
Optimism generally supports well-being, but unrealistic optimism (believing bad things will not happen to you) can increase risky behaviour, such as neglecting contraception or ignoring safety precautions.
Defensive pessimism is the strategic counterpart: deliberately expecting the worst so you prepare harder and often outperform your expectations.
Students often confuse random sampling with random assignment. Random sampling is about who gets into the study (external validity). Random assignment is about who goes into which condition (internal validity). They serve different purposes.
Students often think correlation implies causation. A strong correlation between two variables does not mean one causes the other; a third variable or reverse causation could explain it.
Students mix up mundane realism and external validity. An experiment can look nothing like real life (low mundane realism) yet still produce results that generalise well (high external validity), and vice versa.
Students often confuse self-esteem and self-efficacy. Self-esteem is your overall sense of worth; self-efficacy is your confidence in a specific skill or task. You can have low self-esteem but high self-efficacy in maths, for example.
Know Kurt Lewin's equation cold: B = f(P, S). It often appears as a multiple-choice anchor.
Be able to distinguish correlational from experimental research and explain why only experiments support causal claims.
Expect a question asking you to identify which type of validity (internal vs external) a study design threatens.
The self-serving bias, false consensus, and false uniqueness are frequently tested together. Make sure you can tell them apart and give an example of each.
Understand the difference between the spotlight effect and the illusion of transparency: both involve overestimating others' awareness of us, but the spotlight effect is about appearance and behaviour, while the illusion of transparency is about hidden emotions.
True or False: Random assignment improves external validity. (False. It improves internal validity.)
Fill in the blank: B = f( ___ , ___ ). (Person, Situation)
True or False: A correlation coefficient of r = 0 means the two variables are perfectly related. (False. r = 0 means no relationship.)
Fill in the blank: The tendency to attribute your successes to yourself and your failures to external factors is called the ___ bias. (Self-serving bias)
True or False: The spotlight effect refers to the belief that others can read your hidden emotions. (False. That is the illusion of transparency. The spotlight effect is about overestimating how much others notice your appearance and behaviour.)
Q: A researcher finds that students who sleep more tend to have higher GPAs. Can she conclude that sleep causes better grades? Why or why not?
A: No. This is correlational research, so the direction of causation is unclear and a third variable (e.g. better time management) could explain both. Only an experiment with random assignment could support a causal claim.
Q: In an experiment, participants in the control group happen to be older on average than those in the experimental group. Which type of validity is most directly threatened, and what procedural step could have prevented the problem?
A: Internal validity is threatened because the age difference is a confound. Random assignment would have made the groups equivalent on average.
Q: Explain the difference between the self-serving bias and false consensus, and give one example of each.
A: The self-serving bias is taking credit for successes and blaming failures on external factors (e.g. "I aced the exam because I am smart; I failed because the test was unfair"). False consensus is overestimating how many people share your views (e.g. "Everyone jaywalks, so it must be fine").
Q: A student says, "I know everyone noticed that I spilled coffee in lecture." Which cognitive phenomenon does this illustrate?
A: The spotlight effect, the tendency to believe others pay more attention to our behaviour than they actually do.
Q: How does defensive pessimism differ from simple low self-esteem?
A: Defensive pessimism is a deliberate strategy: the person lowers their expectations before a task and uses the anxiety to prepare harder, often performing well. Low self-esteem, by contrast, is a stable negative self-evaluation that does not necessarily motivate extra preparation.
The self-serving bias introduced here reappears in Chapter 3 (Social Beliefs and Judgements) as part of a broader family of attribution biases, including the fundamental attribution error. Understanding the difference between internal and external attributions starts with the self-serving bias.
The individualism-collectivism distinction in Chapter 2 feeds directly into Chapter 6 (Conformity and Obedience), where collectivist cultures show higher rates of conformity.
Research methods from Chapter 1 are the lens through which every study in the course should be evaluated. When you read about Milgram, Asch, or Festinger and Carlsmith later, ask: What is the independent variable? What is the dependent variable? Is the design experimental or correlational?
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