Ch 2: How Psychologists Do Research Flashcards
Theory
An organized system of assumptions and principles that purports to explain a specified set of phenomena and their interrelationships
Hypothesis
A statement that attempts to predict or to account for a set of phenomena; scientific hypotheses specify relationships among events or variables and are empirically tested
Operational definition
A precise definition of a term in a hypothesis, which specifies the operations for observing and measuring the process or phenomenon being defined
What makes psychological research scientific?
- Precision; use of theories, hypothesis, and operational definitions
- Skepticism; not just about debunking a claim, but showing why the claim is invalid
- Reliance on empirical evidence
- Willingness to make “risky predictions”; that can be refuted, apply to the principle of falsifiability
- Openness; the free flow of ideas, full disclosure of procedures used in a study
Principle of falsifiability
The principle that a scientific theory must make predictions that are specific enough to expose the theory to the possibility of disconfirmation.
Must predict not only what will happen, but what will not happen
Confirmation bias
The tendency to look for or pay attention only to information that confirms one’s own belief
Representative sample
A group of individuals, selected from a population for study, that matches the population on important characteristics such as age and sex
Descriptive methods
Methods that yield descriptions of behaviour but not necessarily causal explanations
Case study
A detailed description of a particular individual being studied or treated
Ex: Behaviour of child that was abused/neglected provides insight into developmental stages at a certain age
Pros: Provides in depth info on individuals; unusual cases can shed light on situations or problems that are unethical or impractical to study in other ways
Cons: Individual may not be representative; memories may be selective or inaccurate; if vital info is missing, then difficult to interpret findings
Observational studies
A study in which the researcher carefully and systematically observes and records behaviour without interfering with the behaviour; it may involve either naturalistic or laboratory observation
Used to describe behaviour, rather than explain why it happens.
Pros: Can see how subjects act in a normal social environment
Cons: In a lab setting it can be hard to maintain natural behaviour
Naturalistic observation
Used to find out how people or animals act in their normal social environment
Pros: Often useful in first stages of a research program
Cons: Researcher has little to no control; observations may be biased; does not identify cause and effect
Laboratory observation
Provides researchers with more control of the situation; access to equipment, control over number of people observed, etc.
Pros: Allows researcher more control; use of sophisticated equipment
Cons: Behaviour may differ from that in a natural environment; observations may be biased; does not identify cause and effect
Psychological tests
Procedures used to measure and evaluate personality traits, emotional states, aptitudes, interests, abilities, and values
Used in education, industry, and scientific research
Pros: Yields info on personality traits, emotional states, aptitudes, and abilities. Can be improvement over self-evaluation, removes distorted view of self
Cons: Difficult to construct tests that are reliable and valid
Objective tests (aka inventories)
Measure beliefs, feelings, or behaviours of which an individual is aware
Projective tests
Designed to tap unconscious feelings or motives
Standardize (tests)
In test construction, to develop uniform procedures for giving and scoring a test
Norms (tests)
In test construction, established standards of performance
Reliability (tests)
In test construction, the consistency of scores derived from a test, from one time and place to another.
When a test produces the same results from one time and place to the next, and from one scorer to another.
Validity (tests)
The ability of a test to measure what it was designed to measure
Surveys
Questionnaires and interviews that ask people directly about their experience, attitudes, or opinions
Pros: Provides a large amount of info on large numbers of people
Cons: Might be impossible to make generalizations if the sample is nonrepresentative; responses may be inaccurate or untrue; people can misinterpret questions
Volunteer bias
A shortcoming of findings derived from a sample of volunteers instead of a representative sample
Correlational study
A descriptive study that looks for a consistent relationship between two phenomena
Pros: Shows whether variables are related; allows general predictions
Cons: Does not identify cause and effect. Ex: A correlates to B, A could cause B, or B could cause A, or they may not directly affect each other
Correlation
A measure of how strongly two variables are related to one another; does not establish causation between variables
Variables
Characteristics of behaviour or experience that can be measured or described by a numeric scale
Positive correlation
An association between increases in one variable and increases in another
Or between decreases in one and decreases in another
Negative correlation
An association between increases in one variable and decreases in another
Coefficient of correlation
A measure of correlation that ranges in value from -1.00 to +1.00
Independent variable
A variable that an experimenter manipulates
Experiment
A controlled test of a hypothesis in which the researcher manipulates one variable to discover its effect on another
Dependent variable
A variable that an experimenter predicts will be affected by manipulations of the independent variable
Control condition
In an experiment, a comparison condition in which participants are not exposed to the same treatment as in the experimental condition
Random assignment
A procedure for assigning people to experimental and control groups in which each individua has the same probability as any other of being assigned to a given group
Placebo
An inactive substance or fake treatment used as a control in an experiment or given by a medical practitioner to a patient
Single-blind study
An experiment in which participants do not know whether they are in an experimental or a control group, but the researchers do
Double-blind study
An experiment in which neither the people being studied nor the researchers know who is in the control group and who is in the experimental group until after the results are tallied
Field research
Descriptive or experimental research conducted in a natural setting outside the laboratory
Descriptive statistics
Statistical procedures that organize and summarize research data
Ex: arithmetic mean, standard deviation
Arithmetic mean
An average that is calculated by adding up a set of quantities and dividing the sum by the total number of quantities in the set
Standard deviation
A commonly used measure of validity that indicates the average difference between scores in a distribution and their mean
Tell us how typical a mean is; narrow distribution indicates mean is more typical; a more spread out distribution indicates mean is less typical
Inferential statistics
Statistical procedures that allow researchers to draw inferences about how statistically meaningful a study’s results are
Ex: significance tests, confidence interval, effect size
Significance tests
Statistical tests that show how likely it is that a study’s results occurred merely by chance
Confidence interval
A statistical measure that provides, with a specified probability, a range of values within which a population mean is likely to be
Cross-sectional study
A study in which people (or animals) of different ages are compared at a given time
Longitudinal study
A study in which people (or animals) are followed and periodically reassessed over a period of time
Effect size
An objective, standardized way of describing the strength of the independent variable’s influence on the dependent variable
Meta-analysis
A set of techniques for combining data from a number of related studies to determine the explanatory strength of a particular independent variable
Bayesian statistics
Statistics that involve a formula for calculating the likelihood of a hypothesis being true and meaningful, taking into account relevant prior knowledge
Informed consent
The doctrine that anyone who participates in human research must do so voluntarily and must know enough about the study to make an intelligent decision about whether to take part
Experimenter effects
Unintended changes in participant behaviour due to cues from researchers; can be limited by a double-blind study
List the principles for studying human beings
- Respect for human dignity
- Respect for free and informed consent; participants join voluntarily and have enough info to make an intelligent decision
- Respect for vulnerable persons; ex: children
- Respect for privacy and confidentiality
- Respect for justice and inclusiveness
- Balancing harms and benefits
- Minimizing harm
- Maximizing benefit
