MCAT PSYCH/SOC: Research Methods, Social Structure, group identity and self identity

Princeton Review 21.1-21.2

Research Methods

The process of conducting and evaluating scientific studies.

Population

The larger group researchers want to study.

Sample

A smaller group selected from the population.

Select the Population

First step in a research study where researchers choose participants.

Independent Variable (IV)

Variable manipulated by the researcher.

Dependent Variable (DV)

Variable measured by the researcher.

Operationalize the Independent and Dependent Variables

Clearly define how variables will be measured and studied.

Operational Definitions

Exact specification of what variables mean.

Why Are Operational Definitions Important?

They make variables measurable and reproducible.

Causal Relationship

When one variable causes changes in another variable.

A → B Relationship

Represents a causal relationship between variables.

Carefully Select Control and Experimental Groups

Researchers organize groups to compare treatment effects.

Control Group

Group that does not receive the treatment.

Experimental Group

Group that receives the treatment or manipulation.

Extraneous Variables

Variables other than the IV that may affect results.

Confounding Variables

Extraneous variables that unintentionally influence the dependent variable.

Why Are Confounding Variables Bad?

They make it difficult to determine true causation.

Homogeneous Groups

Groups made as similar as possible.

Why Use Homogeneous Groups?

To reduce confounding variables.

Double-Blind Study

Neither participants nor researchers know who receives the treatment.

Why Use Double-Blind Studies?

To reduce placebo effects and researcher bias.

Placebo Effect

Improvement caused by belief that treatment works.

Random Sampling

Selecting participants randomly from the population.

Purpose of Random Sampling

To obtain a representative sample.

Representative Sample

A sample that accurately reflects the population.

Random Assignment

Randomly placing participants into groups.

Purpose of Random Assignment

To reduce bias and evenly distribute confounding variables.

Measure the Results

Researchers collect and analyze data from the study.

Test the Hypotheses

Determine whether the prediction is supported.

Hypothesis

A testable prediction about relationships between variables.

Null Hypothesis

Assumes no causal relationship exists and results occurred by chance.

Significant Difference

Difference unlikely to have occurred by chance.

Statistical Significance

Results are unlikely due to random chance.

p-value

Probability that observed results occurred by chance.

p ≤ 0.05

Less than or equal to a 5% probability that results happened randomly.

Lower p-value

Indicates stronger evidence against the null hypothesis.

Reliability

Consistency and repeatability of results.

What Does Reliability Mean?

A study produces similar results repeatedly.

Threats to Reliability

1. Sampling bias
2. Attrition effects

Sampling Bias

When the sample does not accurately represent the population.

Attrition

Participants dropping out of a study.

Internal Validity

Confidence that the Independent Varibable caused changes in the Dependent Variable.

Why Is Internal Validity Important?

It determines whether true causation exists.

Threats to Internal Validity

1. Confounding variables
2. Impression management
3. Demand characteristics

Impression Management

Participants behave according to social expectations.

Demand Characteristics

Cues that influence participants to behave a certain way.

External Validity

Ability to generalize findings to the real world.

Why Is External Validity Important?

It determines whether results apply outside laboratory settings.

Threats to External Validity

1. Experiments not reflecting real life
2. Unrepresentative samples
3. Situational effects

Situational Effects

Artificial conditions that may influence participant behavior.

Statistical Power

Ability of a study to detect real effects.

Larger Sample Sizes

Increase statistical power and reliability.

Disclosure

Informing participants about the study and expectations.

Purpose of Disclosure

To ensure ethical participation and informed consent.

Debriefing

Explaining the true purpose of the study afterward.

Purpose of Debriefing

To clarify deception and explain the study fully.

Researcher Bias

When researchers unintentionally influence results.

Validity

Accuracy of a study and whether it measures what it intends to measure.

Reliability vs Validity

Reliability = consistency. Validity = accuracy.

Main Validity Types

1. Internal validity = causation
2. External validity = generalization

Steps in a Research Study

1. Select the population
2. Operationalize IV and DV
3. Select control and experimental groups
4. Randomly sample participants
5. Randomly assign groups
6. Measure results
7. Test hypotheses

Ways to Reduce Confounding Variables

1. Use homogeneous groups
2. Use control groups
3. Use random assignment
4. Use double-blind procedures

Main Statistical Terms to Memorize

Null hypothesis = no relationship p-value = probability results occurred by chance Statistical significance = unlikely due to chance Statistical power = ability to detect real effects : Most Common Type of Research Design

Correlational Studies

Examine the relationship between two quantitative variables.

Positive Correlation

Two variables increase together.

Negative Correlation

One variable increases while the other decreases.

No Correlation

No direct relationship exists between variables.

Ethnographic Studies

Qualitative studies where researchers immerse themselves in cultures or groups they are studying.

Twin Studies

Studies comparing nature vs. nurture to measure heritability.

Longitudinal Studies

Studies that test how individuals develop over time.

Challenge of Longitudinal Studies

Attrition; they are difficult and expensive.

Case Studies

In-depth examination of one individual, group, or case.

Weakness of Case Studies

Difficult to analyze confounding variables and generalize findings.

Sociology

Study of society and social behavior.

Society

Collective social facts that shape individuals.

Social Facts

Laws, morals, values, customs, and rules that shape society.

Manifest Functions

Intended and recognized consequences of a social structure.

Latent Functions

Unintended or hidden consequences of a social structure.

Example of a Manifest Function

Hospitals treat sick people.

Example of a Latent Function

Hospitals create jobs, bring money into communities, and reduce unemployment.

Structural Functionalism

Theory that society consists of distinct but interrelated parts that maintain stability.

Durkheim

One of the founders of sociology associated with structural functionalism.

Main Idea of Structural Functionalism

Society works together to maintain health and stability.

Social Institutions

Organized structures within society that fulfill social needs.

Examples of Social Institutions

Family, education, religion, economy, and government.

Conflict Theory

Society is a competition for limited resources.

Main Idea of Conflict Theory

Inequality is inevitable because groups compete for power and resources.

Karl Marx

Founder of conflict theory and creator of socialist ideas.

Capitalism

Economic system that creates tension through class struggles over production and control.

Bourgeoisie

Upper class that owns and controls production.

Proletariat

Working class that sells labor.

Ludwig Gumplowicz

Believed conflict was caused by war, conquest, and ethnic group domination.

Max Weber

Agreed capitalism created inequality but believed conflict also involved political power, social status, and mobility.

Symbolic Interactionism

Theory focusing on everyday interactions and communication.

Main Focus of Symbolic Interactionism

Subjective meanings people attach to symbols and interactions.

Symbols

Objects, gestures, or words that carry shared meaning.

Meaning

Shared understanding people attach to symbols.

Dramaturgical Approach

Interactionist theory where people act like performers in everyday life.

Main Idea of the Dramaturgical Approach

People present different personalities depending on the environment.