Experimental Research Methods

What is falsifiability?

The idea that a scientific claim must be testable such that evidence could show it to be unsupported or supported.

What kind of evidence does science rely on?

Evidence that can demonstrate either lack of support or support for a claim.

What are research questions?

Broad questions that guide what a study is trying to understand or explain.

What is a hypothesis?

A specific, testable prediction derived from a research question.

How are hypotheses similar to hypothesis testing?

Researchers make different predictions for expected results depending on whether the hypothesis is supported or not.

What observation supports or refutes a hypothesis?

Direct observations or measurements that align with or contradict the predicted outcomes.

Why should scientists avoid saying “prove” or “disprove”?

Because scientific findings provide evidence for or against claims, not absolute proof.

What must an experiment allow for?

Alternative outcomes must be possible.

What is empiricism?

Direct, systematic observation and measurement.

Why are clear variable definitions important?

Specificity ensures variables can be observed, measured, and replicated.

What does method refer to in science?

How data are collected.

Why is previous research important?

It informs study design and helps refine questions and methods.

What kind of knowledge does empiricism produce?

Knowledge gained through observation and measurement.

What is reproducibility?

The ability for others to replicate a study using sufficient documented detail.

What is transparency in research?

Providing enough detail so others can independently verify or reproduce the study.

What question assesses transparency?

Could someone reproduce the study without consulting the original researcher?

What does reproducibility support?

Objective and neutral research.

What does “This I Believe” knowledge rely on?

Authority, experience, or intuition rather than systematic evidence.

How can beliefs based on authority be formed?

Through the authority’s research, personal experience, or intuition.

What characterizes beliefs based on experience?

Lack of comparison groups and presence of confounds.

What characterizes beliefs based on intuition?

Compelling stories and cognitive biases.

What is availability bias?

Judging likelihood based on how easily examples come to mind.

What is present bias?

Overweighting immediate information or experiences.

What is confirmation bias?

Seeking or interpreting evidence to confirm existing beliefs.

What is bias blind spot?

Recognizing biases in others but not in oneself.

What is repeatability?

Same researcher using the same data; low cost and low effort.

What is reproducibility (modern usage)?

New researcher using the same data; mid-cost and mid-effort.

What is replicability?

New researcher collecting new data; high cost and high effort.

What is the difference between direct and conceptual replication?

Direct uses the same procedures; conceptual tests the same question with different procedures.

What question did the line study investigate?

Whether participants would continue to conform to group consensus.

What does psychological science involve?

Systematic evidence collection and evaluation of the weight of evidence.

Why is consensus important in psychological science?

It reflects replication and reliability of findings.

What are the goals of psychological science?

Describe, predict, determine causes, and understand behavior.

What is NOT a goal of psychological science?

Proving claims.

What is development?

Age-related change, processes that facilitate change, and mechanisms responsible for change.

Why can’t development always be manipulated?

Age and natural change cannot be experimentally controlled.

What is a developmental mechanism?

A causal process producing predictable patterns of change.

What is productive continuity?

Development where earlier changes causally produce later changes.

What example links SES and language development?

Language growth correlates with SES due to resource access, time, and stress—not SES itself.

Can a single study discover a developmental mechanism?

No, but studies can be informed by existing theories and mechanisms

How is statistical learning examined experimentally?

By comparing systematically exposed groups to control groups.

What is an example of developmental milestones?

Babbling at 6 months and ~50 words by age 2.

What is a factor in developmental research?

A variable like socioeconomic level.

What is an impact?

The outcome, such as amount of language learned.

What is a mechanism?

The process explaining the impact, such as statistical learning.

How should development be incorporated into research?

By focusing on individual differences, age-related change, factors, and mechanisms.

What is cross-sectional research?

Comparing different age groups at one point in time.

When is a study an experiment?

When the researcher intentionally manipulates a variable.

What is an independent variable (IV)?

A variable manipulated or controlled by the experimenter.

What are factors and levels?

Factors are IVs; levels are the specific values they take.

What is a dependent variable (DV)?

The measured outcome of the study.

What other variables may be included in experiments?

Covariates and grouping variables.

What is validity?

The extent to which a study demonstrates what it claims.

What is internal validity?

Confidence that the IV caused changes in the DV.

What threatens internal validity?

Confounds.

What is external validity?

The ability to generalize findings beyond the study.

What is ecological validity?

How well findings apply to real-world settings.

What is construct validity?

How accurately measurements represent theoretical constructs

What is selection bias?

Nonrandom recruitment or assignment of participants.

Why is selection bias a problem?

It threatens both internal and external validity.

What is selective dropout?

Systematic loss of participants from a study.

Why is selective dropout concerning?

It threatens ecological validity.

What is reactivity?

Changes in behavior due to awareness of being studied.

What is the Hawthorne Effect?

Participants change behavior because they know they are observed.

What is social desirability bias?

Participants respond to appear favorable.

What are demand characteristics?

Participants act based on perceived study goals.

What is evaluation apprehension?

Behavior changes due to self-consciousness.

How can reactivity be reduced?

Blinding, deception (ethically), post-experiment interviews, and less direct measures.

What is instrumentation bias?

Unintended changes in measurement tools or procedures.

What is mono-operation bias?

Using only one operational definition of a variable.

What is mono-method bias?

Using only one measurement method for a construct.