Introduction to Research Methods in Psychology – Prof. Douglas Elliffe

A comprehensive set of question-and-answer flashcards covering key concepts from the lecture on research methods: scientific norms, variables, reliability and validity, sampling, design types, confounds, and experimental controls.

Why are systematic research methods important when answering questions like “Does social media affect mental health?”

They provide structured, evidence-based ways to test claims instead of relying on opinion or anecdote.

What are Merton’s simplified norms for science?

Communality, Universalism, and Organized scepticism.

What does the norm of Communality state?

Scientific knowledge is shared property of humanity and must be openly available.

Why is the flatworm ‘memory transfer’ study a cautionary tale?

Its dramatic finding could not be replicated, showing the need for good design and replication.

What two major things can go wrong with a study, as illustrated by the flatworm example?

A fluke statistical result or flawed research design.

In research terminology, what is the Dependent Variable (DV)?

The behaviour or outcome measured by the researcher; plotted on the y-axis.

In research terminology, what is the Independent Variable (IV)?

The factor the experimenter manipulates to observe its effect on the DV; plotted on the x-axis.

Give the IV and DV in a Stroop task measuring colours named in 30 s when print colour matches or mismatches the word.

IV = Match vs. mismatch condition; DV = Number of colours named in 30 seconds.

Define reliability in psychological measurement.

The degree to which repeated measurements of the same variable yield the same results.

Define validity in psychological measurement.

The extent to which a measure actually captures the construct it is intended to assess.

Can a measure be reliable but not valid? Give an example.

Yes; shoe size measured reliably cannot validly assess intelligence.

What is a population in research?

The entire set of scores, events, or individuals of interest (e.g., heights of the whole PSYCH109 class).

What is a sample?

A representative subset of the population from which data are actually collected.

Explain sampling error.

Natural variability causing different random samples from the same population to yield different results; reduced by larger samples.

Explain sampling bias.

Systematic misrepresentation of the population by the sample, often due to non-random selection.

Why did the 1948 telephone poll wrongly predict Dewey would beat Truman?

Phone ownership over-represented wealthier Republicans, producing sampling bias.

What does WEIRD stand for in participant sampling criticism?

Western, Educated, Industrial, Rich, and Democratic.

State the key warning about observational (correlational) designs.

Correlation does not imply causation.

Describe the third-variable problem.

A separate variable may cause both variables in a correlation, creating a spurious relationship.

When is an observational design preferable?

When manipulation is unethical or impractical (e.g., mapping Broca’s area via natural lesions).

How does an experimental design overcome the causation issue?

By manipulating an IV and controlling confounds to observe its direct effect on a DV.

What is a confounding variable?

Any factor other than the IV that could have produced the observed change in the DV.

Name two general strategies for eliminating confounds.

Holding the confound constant (standardization) and randomizing the confound across conditions.

What is a within-subjects (repeated-measures) design?

Each participant experiences all levels of the IV and is compared to themselves across conditions.

Main advantage of within-subjects designs?

They control subject-based confounds because each person serves as their own control.

Main disadvantage of within-subjects designs?

Susceptible to environmental confounds such as order or practice effects.

What is a between-groups (independent-samples) design?

Different participants experience different levels of the IV; comparisons are made between group means.

Main advantage of between-groups designs?

They avoid order effects because each participant is tested in only one condition.

Main disadvantage of between-groups designs?

Subject confounds may arise if groups differ systematically; random assignment helps reduce this.

Describe a matched-pairs design.

Participants are paired on a pre-test variable, then each member is randomly assigned to a different condition, combining benefits of both major designs.

Why is matched-pairs considered powerful yet underused?

It controls both subject and environmental confounds but is labour-intensive to set up.

What is a control group?

A group treated identically to the experimental group except for the critical IV manipulation.

Why use single-blind procedures?

To prevent participants’ expectations from influencing outcomes by keeping them unaware of group assignment.

Why use double-blind procedures?

To prevent both participant and experimenter expectations from biasing results, preserving objectivity; considered the research ‘gold standard’.

Give an example of standardization as a way to control confounds.

Testing all participants in the same quiet room with identical instructions and lighting.

How can random assignment reduce subject confounds in a between-groups study?

It distributes individual differences (e.g., intelligence, motivation) evenly across conditions by chance.

What ethical obligation is highlighted for psychological research compared to other sciences?

Because participants are usually people and results affect treatment of people, studies must avoid wasting participants’ time and ensure methodological soundness.

Why must Psychology students study statistics?

Statistics allow researchers to determine whether observed effects could be due to chance, addressing fluke results.

If extraversion might confound a social-behavior study, name two design steps to minimize its impact.

(1) Measure extraversion and use matched-pairs or statistical control; (2) Randomly assign participants to conditions to balance extraversion levels across groups.

State the fundamental principle of research design articulated in the lecture.

Eliminate all alternative explanations (confounds) so any DV change can be attributed solely to the IV.