Unit 1 History Of Psychology & Research Method

Psychology

The scientific study of the mind and behavior.

Basic psychology

Research done to expand knowledge of psychological processes; not for immediate practical use.

Applied psychology

Using psychological principles to solve real-world problems.

Goals of psychology

To describe, explain, predict, and control/change behavior.

Subfields of psychology

Include clinical, counseling, developmental, cognitive, biological, social, industrial-organizational, health, forensic, etc.

Empiricism

Knowledge comes from observation and experience rather than pure logic or intuition.

Psychoanalytic perspective

Behavior is driven by unconscious desires and conflicts (Freud).

Behavioral perspective

Behavior is learned through conditioning and reinforcement (Watson, Skinner).

Humanistic perspective

Emphasizes personal growth, free will, and reaching one’s potential (Rogers, Maslow).

Cognitive perspective

Focuses on thinking, memory, problem-solving, and information processing.

Evolutionary perspective

Behavior and mental processes are shaped by adaptation and survival (Darwin).

Natural selection

Traits that aid survival and reproduction are passed on.

Biological perspective

Behavior explained by brain structures, neurotransmitters, genetics, and hormones.

Socio-cultural perspective

Behavior influenced by social interactions, culture, and environment.

Biopsychosocial model

Combines biological, psychological, and social factors to explain behavior.

Hindsight bias

Believing you 'knew it all along' after something happens.

Overconfidence

Thinking you know more than you actually do.

False consensus effect

Assuming others share your beliefs/behaviors more than they actually do.

Confirmation bias

Focusing on evidence that supports your beliefs and ignoring what contradicts them.

Scientific method

Process of forming a hypothesis, collecting data, analyzing results, and drawing conclusions.

Qualitative measures

Descriptive data (interviews, observations, open-ended responses).

Self-report

Participants report on themselves (surveys, questionnaires).

Social desirability effect

Participants give answers they think look good rather than truthful ones.

Framing (wording effects)

How a question is worded influences responses.

Quantitative measures

Numerical data (scores, test results).

Likert scale

Rating scale (e.g., 1–5 from 'strongly disagree' to 'strongly agree').

Peer review

Research checked by experts before publication.

Naturalistic observation

Observing behavior in real-life settings without interference.

Hawthorne effect

People change behavior when they know they’re being observed.

Laboratory observation

Observing behavior in a controlled setting.

Case study

In-depth study of one person or small group.

Meta-analysis

Combining results of many studies to find overall patterns.

Scatterplot

Graph showing relationship between two variables.

Correlation coefficient (r)

Number between –1 and +1 showing strength/direction of a relationship.

Positive correlation

Variables move in the same direction.

Negative correlation

Variables move in opposite directions.

Directionality problem

Can’t tell which variable causes the other in correlations.

Line of regression

Best-fit line showing relationship trend in a scatterplot.

Hypothesis

Testable prediction.

Independent variable (IV)

What the experimenter changes.

Dependent variable (DV)

What is measured (outcome).

Population

The entire group being studied.

Sample

Smaller group studied from the population.

Representative sample

Reflects important characteristics of the population.

Sampling bias

When the sample doesn’t represent the population.

Random selection

Each person in the population has an equal chance of being chosen.

Convenience sampling

Choosing participants who are easiest to reach.

Experimental group

Receives treatment/IV.

Control group

Does not receive treatment; used for comparison.

Placebo

Fake treatment used to test effects of expectation.

Random assignment

Randomly placing participants in experimental/control groups.

Quasi-experimental design

Uses existing groups instead of random assignment.

Operational definition

Specific, measurable definition of variables.

Replication

Repeating a study to see if results hold.

Reliability

Consistency of results.

Confounding variable

An outside variable that could affect results.

Validity

Whether a study measures what it’s supposed to.

Placebo effect

Improvement due to belief in treatment, not the treatment itself.

Single-blind study

Participants don’t know group assignment.

Experimenter bias

Researcher unintentionally influences results.

Double-blind study

Neither participants nor researchers know group assignments.

American Psychological Association (APA)

Sets ethical guidelines for psychologists.

Institutional Review Board (IRB)

Approves research for ethical safety.

Informed consent

Participants agree after being told details.

Informed assent

Children/minors agree (with parental consent).

Debriefing

Explaining the study to participants afterward.

Research confederates

Actors secretly part of the study to influence participants.

Histogram

Bar graph showing frequency distribution.

Measures of central tendency

Ways to describe the 'center' of data.

Mode

Most frequent value.

Mean

Average.

Median

Middle score.

Normal curve

Bell-shaped, symmetrical distribution.

Positively skewed distribution

Tail to the right (high outliers).

Negatively skewed distribution

Tail to the left (low outliers).

Multimodal distribution

More than one peak (bimodal = 2 peaks).

Measures of variability

How spread out data is.

Range

Difference between highest and lowest.

Standard deviation

Average distance from the mean.

Z score

Number of standard deviations a score is from the mean.

Percentile rank

Percentage of scores at or below a given score.

Inferential statistics

Determine if results can be generalized.

p value

Probability results are due to chance (p < .05 = significant).

Statistical significance

Results unlikely due to chance.

Regression toward the mean

Extreme scores tend to move closer to average on retest.

Effect size

Strength of the relationship between variables.

Wilhelm Wundt

'Father of psychology,' opened first psych lab (1879).

Sigmund Freud

Founder of psychoanalysis; unconscious drives behavior.

John B. Watson

Founder of behavioral perspective; 'Little Albert' study.

Carl Rogers

Humanistic psychologist; client-centered therapy.

Charles Darwin

Theory of evolution; natural selection influences behavior.