Empiricism and Research Methods in Psychology

Empiricism

Knowledge gained through observation and experimentation.

Empirical study

Gaining knowledge via observation, essential for science.

Rationalism

Knowledge gained through reasoning and logic.

Scientific method

Rules guiding the relationship between ideas and evidence.

Theory

Ideas about how and why phenomena occur.

Hypothesis

Falsifiable prediction derived from a theory.

Addiction theory example

Link between parental addiction and children's addiction.

Four objectives of psychological science

Describe, explain, predict, and control behaviors.

Describe (objective)

Understanding characteristics of a behavior.

Explain (objective)

Understanding conditions reproducing a behavior.

Predict (objective)

Determining future behaviors in advance.

Control (objective)

Applying knowledge to influence real-world outcomes.

Population

All individuals of interest in a study.

Sample

Partial collection of individuals from the population.

Random sampling

Method to ensure sample represents the population.

Independent variable (IV)

Variable grouping participants into different categories.

Dependent variable (DV)

Variable measured to assess effects of IV.

Handwriting vs. typing study

IV: Note-taking method; DV: Test scores.

Breakfast impact study

IV: Breakfast provision; DV: Student grades.

Multiple IVs and DVs

Studies can include several independent and dependent variables.

Research challenges in psychology

Complexity, variability, and reactivity of human behavior.

Psychologist's focus

Study of mind and behavior in humans and non-humans.

Measurement

Device detecting the condition of an operational definition.

Validity

Extent of conceptual relationship between measurement and property.

Reliability

Consistency of a measure producing the same results.

Power

Ability to detect specified conditions in operational definition.

Operational Definition

Concrete, measurable description of the observed property.

Demand Characteristics

Aspects causing people to behave as expected.

Internal Validity

Causal relationship established between variables in an experiment.

External Validity

Generalizability of findings to the broader population.

Observer Bias

Expectations affecting interpretation of observations.

Double-blind

Both observer and participant unaware of study purpose.

Experimental Studies

Research manipulating independent variable with random assignment.

Quasi-experimental Studies

Research lacking random assignment, cannot show causation.

Correlational Studies

Research examining relationships between variables without manipulation.

Correlation

Statistical relationship between two variables, not causation.

Correlation Coefficient

Numerical value indicating strength and direction of correlation.

Positive r-value

Indicates upward trend in data relationship.

Negative r-value

Indicates downward trend in data relationship.

Random Assignment

Participants assigned randomly to control for biases.

Causation

Claiming one variable directly affects another.

Quantitative Data

Data expressible in numerical form.

Natural Experiments

Observations in real-world settings without manipulation.

Measurement Dependence

Effect measured may vary based on measurement method.

Qualitative Data

Data that cannot be expressed numerically.

Descriptive Statistics

Summarizes data using measures like averages.

Inferential Statistics

Draws conclusions about hypotheses from data.

Mean

Average value of a data set.

Median

50th percentile; divides data in half.

Mode

Most frequently occurring value in data.

Standard Deviation

Measures how spread out data is.

Normal Distribution

Symmetrical distribution with mean at center.

Negatively Skewed Distribution

Low frequency of extreme low scores.

Positively Skewed Distribution

Low frequency of extreme high scores.

R-Values

Indicates strength of correlation between variables.

P-Values

Probability results occurred by chance under null hypothesis.

Statistical Significance

Results unlikely if null hypothesis is true.

Effect Sizes

Measures strength of relationship or impact.

Tuskegee Syphilis Experiment

Unethical study observing untreated syphilis progression.

Institutional Review Board (IRB)

Ensures ethical standards in human research.

APA Ethics

Guidelines for ethical psychological research.

Informed Consent

Participants must understand and agree to research.

Freedom from Coercion

Participants should not be pressured to join.

Protection from Harm

Research must minimize risks to participants.

Risk-Benefit Analysis

Evaluates potential risks against research benefits.

Confidentiality

Participants' data must be kept private.